THE “GENERAL MORPHOLOGY”
The speech at the Scientific Congress in 1863 was the first open
confession that Haeckel felt bound to make. But the real work for the
new ideas began on his return to Jena. Nothing was further from
Haeckel’s thoughts at that time than the idea of becoming merely the
populariser of Darwinism in Germany. He has often been spoken of since
in lay circles as such. It is entirely wrong. He had the courage to
recognise his debt whenever he contracted one; and certainly Darwin
supplied the groundwork of his colour-scheme. But he was much too
independent and individual in his nature not to take the axe in his own
hand at once and begin to hew away himself.
Darwin had strengthened his book with a large amount of the best
material that zoology and botany could supply. But there was something
else to be done: a theoretical treatment of a general character with
cleverly grouped illustrations from the facts already provided by two
sciences, and to reconstruct these sciences from their foundations on
the basis of the new theory. At that time Haeckel was doing an
incredible amount of work, with body and mind. He had an iron
constitution. In the year of the Stettin speech he won a laurel crown at
the Leipsic athletic festival for the long jump, with a leap of twenty
feet. His physical strength seemed so inexhaustible that his host,
Engelmann, put a pair of heavy iron dumb-bells in his bed, in case he
should want to take exercise during the night. He had a proportionate
strength of mind. Everything seemed to promise very well for the next
few years, so that he could devote his whole health and strength to the
great task of his life. His teaching did not give him very much trouble
in a small university like Jena, that was only just beginning to have a
scientific name. The happiness of his home life, with a highly gifted
woman who shared all his ideas with the freshness of youth, began to
chain the restless wanderer with pleasant bonds to his place. He, of
course, expected to have his sea-holiday in the old way for the study of
his little marine treasures, but otherwise he remained quietly in the
valley of the Saale. The warmth of genial and most stimulating
friendships gathered about his life. With his comfortable material
position he set to work on his great task under the best auspices.
He would have had at the start material enough to work upon without
Darwin. From Müller’s time he still had another special class of
material, similar to the radiolaria, the medusæ.
The ship cuts through the ocean. It rises like a lofty fortress from the
illimitable blue plain, with the white clouds on the far horizon. No
land has been in sight for days. Yesterday a poor wind-borne butterfly
rested on the deck. To-day it is gone, and all is sea. Then they
suddenly appear silently in the blue mirror: mysterious discs, red as
the anemones on a Roman meadow in spring, golden as the autumn leaves on
a dark pond in the park, then blue, like a lighter blue floating on the
general azure. They are the medusæ. At one time the ship sails through a
whole swarm of them—thousands, hundreds of thousands, millions, a
veritable milky way of coloured stars. On the next day they have all
gone. No inhabitant of the ocean seems to be so close to it as this
creature. The whole animal is only a shade more substantial than the
water. You take it out, and try to catch hold of it. It stings your hand
like a nettle: that is its one weapon. But it is already destroyed,
melted away, a formless nothing. You put it on a piece of
blotting-paper, and it dries up into the spectral outline of a shadow, a
tiny “fat-spot,” summary of its whole existence.
Yet this soap-bubble of the water is a real animal. Its transparent body
is shaped like a bell, and moves through the water by regular
contraction and expansion, like the lung in breathing. Where the clapper
of the bell should be, we find a stomach, with a mouth for eating,
hanging down from the curved upper part. At the edge of the curved
surface are many long fibrils that close on the approaching prey and
paralyse it by their sting. Then it thrusts it into its mouth and
swallows the object into the stomach. The medusa is, of course, a very
lowly creature, but it is much more advanced in organisation than the
tiny radiolarian. The radiolarian consists of a single cell. The medusa
is a cell-state, a community of countless cells with a division of
labour amongst them. Some of the cells form the wall of the bell, some
the stinging threads, some the devouring and digesting stomach. In this
the medusa comes nearer to man than the radiolarian. Some of the cells
see to the reproduction of the medusa. Ova and spermatozoa are detached
from the cell-community of the medusa’s body, blend together, and thus
form the germ of a new medusa. In most cases the process is curious
enough. From the germ-cell we get at first, not a real medusa, but a
polyp that attaches itself to the ground, a little creature that may be
remotely compared to the pretty water-lilies that meet the eye in an
aquarium. Then the polyp produces something like a plant that grows
buds, the real medusæ; it may produce these out of its substance as
buds, and they then float away like detached flowers, or (in other
species) it may gradually change itself into a chain of medusæ, of which
the uppermost is detached first, then the next, and so on.
Since this peculiar method of reproduction became known, in the thirties
or forties, the medusæ were regarded as amongst the most interesting
objects in the whole of zoology. They offered an extremely difficult
task to the investigator who would care to take up the study of them.
When Haeckel was with Johannes Müller in Heligoland in 1854 he made
acquaintance with them for the first time. His artistic eye was caught
with their beauty, as it was afterwards with the radiolaria. “Never
shall I forget,” he says, “the delight with which, as a student of
twenty years I gazed on the first _Tiara_ and _Irene_ [species of
medusæ], and the first _Chrysaora_ and _Cyanea_, and endeavoured to
reproduce their beautiful forms and colours.” His predilection for the
medusæ never disappeared. At Nice in 1856 he met them again in the
Mediterranean. Gegenbaur’s _Sketch of a Classification of the Medusæ_
provided his studies with a starting-point, just as Müller’s writings
did afterwards for the radiolaria. At Naples and Messina he completed
his mastery of them. When he had done with the radiolaria for the time
after publishing the great monograph of 1862, the next task that loomed
up on his horizon was the need for a “monograph on the medusæ.” It would
be a long time, however, before he could complete the work in any
fulness. A work of Agassiz that purported to do it, but, in his opinion,
only confused the subject—he disliked both the Agassizs, father and son,
and the father became one of his bitterest opponents on the Darwinian
question—gave him a negative impulse to the study. He thought it would
be best to deal with one family of the medusæ after another in separate
monographs, as time permitted. The first of these essays appeared in
1864 and 1865, and dealt with what are known as the “snouted-medusæ”
(_geryonidæ_). The first volume of the complete work was not published
until fourteen years afterwards. If Haeckel had decided to work as a
specialist he would have had material enough here to occupy him fully
throughout the whole of the sixties, and even longer. The keen student
of the radiolaria would be succeeded by the equally keen student of the
medusæ. More folio volumes would have accumulated, with beautiful
plates, such as only the technical student of zoology ever takes out of
the library. His name, like that of his friend Gegenbaur almost, would
never have reached the crowd.
It was the influence of Darwin that prevented this. His attention was
turned in another direction, and we begin to realise the full greatness
of his power when we remember that he nevertheless continued with
unfailing quality to publish such detailed studies as those on the
medusæ.
Darwinian ideas were fermenting intensely in his mind at that time. The
most audacious practical and theoretical problems arose from the
fundamental theory, and forced themselves on him at every moment. A
great deal was sketched in outline in the Stettin speech, but the
serious scientific work would have to be begun on his return to Jena, in
his view. First, he thought, two features of Darwin’s system must be
given a completely new and original complexion. Firstly, the bottom of
the tree, where life begins. Secondly, the crown of all terrestrial
evolution: the manner in which man is connected with the tree. It was
his philosophic vein that settled both points, the philosophy of unity
that sought to replace God by natural development, both below and above,
in regard to the primitive cell and in regard to man. But the way in
which he set about it was very far removed from all conventional
philosophy. The whole rigour of his professional zoology found
expression in it. And that was really the novelty of it. The same
conclusions might have been drawn by any dozen ordinary philosophers,
once they got on the right track. Even they could see that, if two and
two are four, one and one are two, and three times three nine. Haeckel
went very differently, and much more profoundly, to work.
[Illustration:
ERNST HAECKEL, 1890.
_From a relief-portrait modelled by Kopf, of Rome._
]
As an old pupil of Virchow’s he applies the cell-theory to Darwinism—in
the lower stage. The first living things, the roots of the great tree of
life, consisted of a single cell. The logic of the cell-theory itself
went as far as this. But is the individual cell the simplest of all
living forms? Here there was a long-standing controversy as to
definitions. At first the cell was regarded literally as a kind of
chamber, like the cell in the honeycomb. Then it was found that the
jelly-like, mobile matter within the cell-chamber was the essential
element, the vehicle of life. Finally, it was possible to conceive this
slimy substance without any firm membrane, without a chamber. Inside it,
however, there was always (it was then thought) a thick and hard
substance, the nucleus. If that was the fundamental and only really
essential form, the Darwinian primitive and initial type of all
terrestrial life must have been a similar drop of living matter with a
solid central nucleus, a nucleated individual cell.
How could we pass from this primitive cell to the “inorganic,” the
“lifeless,” the “dead,” the ordinary matter of stone, metal, and
crystal? Haeckel believed that it was possible to make a step in that
direction—not theoretically and philosophically, but practically—by
showing that there were still living things on the earth that did not
come up to the definition of a true cell, things that had not yet a
nucleus in their soft gelatinous body. He discovered a number of tiny
creatures that had a homogeneous particle of living matter for body, and
showed no trace of a nucleus. The nucleus seemed to be the first
beginning of an organ. It was altogether wanting in them.
To these most primitive of all living things he gave the name of
_monera_, or the absolutely “simple.”
In these investigations it is very difficult to determine whether one of
these tiny drops of plasm has a more or less transparent nucleus or not.
It has often been affirmed in later years that these monera of Haeckel’s
did not correspond to their description as living things without a
nucleus, or creatures that were below the level of the true cell. It is,
at all events, certain that there are to-day large numbers of the
unicellular beings known as the bacteria in which no nucleus has yet
been discovered by the most sceptical Thomas with the most powerful
microscopes and best technical appliances of our time. It is the same
with the chromacea (chroococci, oscillaria, nostoc-algæ), very lowly
primitive plants whose whole body consists of a globule or granule of
living plasm. However, here again the question is no longer of the first
importance, now that evolution is entirely and generally accepted. At
the time we are discussing the method chosen was all-important. Haeckel
drew no conclusions without a solid basis. He believed he could give
ocular proof of the existence of beings that were below the level of the
cell. It was clear, at all events, that research in this department was
only in its beginning, and could pour out wonder after wonder before the
world recovered from its first fright over Darwinism.
Then there was the other end of the system—man. Here again it was not
merely a question of concluding on philosophic grounds that man _must_
have descended from the lower animals. Huxley had dealt in England with
the question of man and the ape on the strict lines of zoology. He came
to the important conclusion that man differs _less_ zoologically from
the highest apes, the gorilla and chimpanzee, than they do from the
lowest apes. He proved his point by a technical study of skulls and
brains, not from abstract philosophical principles. It could be
demonstrated in the museum or zoological institute to any student with
some knowledge of anatomy as easily as the existence and position of any
particular bone in the skeleton. Haeckel went even further.
He constructed a genealogical tree stretching far below the apes. Next
to them came the lemurs. The lemur, the ghostly nocturnal inhabitant of
Madagascar, came from the Australian marsupial (kangaroo, &c.). The
marsupial came from the duck-bill; the duck-bill from the lizard; the
lizard from the salamander; the salamander from the dipneust or
mud-fish; this from the sturgeon or the shark, and the shark from the
lamprey. Below the lamprey, at the lowest limit of the vertebrate
kingdom, was the amphioxus (or lancelet). This must have come from the
worm—it was not at all clear how, at that time. And so the series ran on
down to the unicellular protozoa, the amœbæ and the monera.
The construction of this tree would have been impossible for one who had
not already done gigantic work. The whole of the new system of animals
and plants, conceived in the form of a genealogical tree, had first to
be sketched in outline. Then the narrower thread that led up to man, the
Ariadne-thread of God-Nature, would gradually come to light.
Both ends of the system, the lower one in the monera, the upper one in
man, were first thoroughly treated by him in 1865, and in part somewhat
later. His exhaustive _Monograph on the Monera_ was not published until
1868. Man’s genealogical tree was privately circulated at Jena in two
essays in October and November 1865. They were published in the
Virchow-Holtzendorff collection in 1868 (“The Origin and Genealogical
Tree of the Human Race”). But in both cases the substance of the work,
as an accumulation of facts, is much older. And this work was, of
course, only possible in connection with a number of further
conclusions: in regard to spontaneous generation, life and death, the
crystal and the cell, the mathematical form of organisms, the nature and
limits of individuality, the method of research, the new natural
philosophy, God, and so on.
It was an enormous programme, with a Paradisaic freshness. Everything
was new and great; and all came from one brain. There was only one man
with whom he discussed his ideas as they formed, Carl Gegenbaur, who has
undoubtedly had a great, if unconscious, influence on them. Haeckel’s
grateful recognition of Gegenbaur’s help in later years was endless and
touching. “Thou it was,” he writes to him a little later, “that led me
to begin my academic teaching at our beloved Jena six years ago, at the
Thuringian university in the heart of Germany, that has, like a beating
heart, sent out its living waves of freedom and alertness of mind over
Germany for three hundred years. At this nursery of German philosophy
and science, under the protection of a free State whose princely rulers
ever gave a refuge to free speech and have linked their names for ever
with the reform movement, the golden age of German poetry, I was able to
work in association with thee. Here we built up our common structure of
science in the happiest division of labour, teaching and learning
cordially from each other, in the very rooms in which Goethe began his
studies of ‘the morphology of organisms’ a half-century before, and
partly with the same scientific means, the germs of comparative and
philosophic science that he had scattered. We have shared with each
other as brothers the happiness and the sorrow that came in the hard
struggle for life, and our scientific efforts have been so intimately
blended and so mutually helpful, through our daily working and talking
together, that it would have been impossible for either of us to
determine the particular share of each in our spiritual communism. I can
only say in a general way that the little my restless and impulsive
youth could offer thee here and there is out of all proportion to the
enormous amount I have received from thee, eight years my senior, a more
experienced and mature man.”
Goethe stood behind the friends as the quiet _genius loci_, giving his
blessing to all who worked in his spirit on the old spot. Nor was the
place itself without influence. “Much,” Haeckel writes, “may have been
even the outcome of the common uplifting enjoyment of nature that was
afforded us by the artistic lines of the Jena hills, as they brought
before us once more at sunset the magic of the Calabrian mountains by
the colour-harmony of their purple and gold banks of cloud and their
violet shadows.”
“What are the hopes, what are the plans, that man, the creature of a
day, builds up?”
The words were written by a poet, in his fatal illness, at the spot
where the two strong spirits now worked. In the midst of all his hopes
and plans Haeckel was struck by a Niobe-shaft. On February 16th, 1864,
just on his thirtieth birthday, his wife, only in her twenty-ninth year,
in the full force of mind and of love, succumbed to blood-poisoning.
I turn to the thick volume of Haeckel’s _Monograph on the Medusæ_. Part
I.: “System of the Medusæ:” with an atlas of forty beautiful plates:
published by Gustav Fischer, of Jena, in 1879. Few people except
zoologists with a technical interest in it have ever opened this
voluminous work—why should they? It is a heavy work, with dry diagnoses.
The author seems to be far away from all general questions, if ever he
was, in the utter stillness of his study. This pure accumulation of
matter for truth’s sake does not reach the ear of the world. It lays up
material for remote days, before which the individual fades away; it is
merely catalogued material of the most technical character. Yet, as I
turn over the pages, I seem to see a little image from time to time that
is almost like the rose-red or golden-brown medusæ in the sterile,
illimitable ocean. In truth neither ocean nor book is sterile; but they
are grey and broad. And just as the swimming medusa gladdens me in the
one, so a little personal trait of the author does in the other. It is
in the choice of the Latin names. A little crown is woven that unites
æsthetics and science. I find splendid names, invented by the Professor,
on all sides. But I notice that his heart was in these things. He has
discovered new species of medusæ, and must christen them. As he turns
over his Latin or Greek lexicon a ray of humanity steals into the most
severe scientific soul at such moments. I read that a disco-medusa is
called the _Nausicaa phæacum_: “I observed the _Nausicaa phæacum_ in
April, 1877, at Corfu, on the shore of Phæaca, in the heart of the
Nausicaa.” A cyaneid is given the fine name of the _Melusina formosa_.
It is noted, with great regret, that “so fine and classic a name for a
medusa” as _Oceania_ must be struck out on scientific grounds. Amongst
descriptions of species in a severe scientific tongue that unnerves the
timid reader, amongst gonods, styles, perradial bundles of tentacles,
and ocellar bulbs, we find, _apropos_ of the medusa, _Lizzia
Elisabethæ_: “As Forbes dedicated the pretty genus _Lizzia blondina_ to
a ‘blond Elizabeth,’ I do the same, and wish to honour, not only St.
Elizabeth of Thuringia, but also the ‘blond Elizabeth’ of Immermann and
my own dear daughter Elizabeth.”
Then, in the middle of the large volume, we find the following passage
on page 189. A medusa is given the name of _Mitrocoma Annæ_. The name
was given at Villefranche, near Nice, in April, 1864 This medusa had “a
fairy-like appearance” to its discoverer; its tentacles hung down “like
a mass of blond hair!” A note to the name tells us that it was given “in
memory of my dear, never-to-be-forgotten wife, Anna Sethe. If it is
given to me to do something during my earthly pilgrimage for science and
humanity, I owe it for the most part to the blessed influence of my
gifted wife, who was torn from me by a premature end in 1864.” In the
_Art-forms in Nature_, Haeckel’s work of 1899, we find a medusa
_Desmonema Annasethe_ similarly—after thirty-five years—apostrophised:
“The specific name of this pretty disco-medusa, one of the most
beautiful and interesting of all the medusaæ, immortalises the memory of
Anna Sethe, the gifted and refined wife (born 1835, died 1864) to whom
the author of this work owes the happiest years of his life.”
If one would fathom the depths of human emotion one must reflect what
these words, in such a context, contain; it is the last gentle vibration
of a most deep inner experience breaking out into this prosaic,
scientific material. A medusa is a trivial, possibly a funny thing, to
the layman. The man of science looks deeper into it, and sees a
wonderful revelation of nature; the eye of Goethe’s God shines on him
from it. But when he has devoted years to the most careful study of it,
it assumes also a naïve individual interest for him, as the companion of
his solitary hours of observation in the heart of nature, far from all
the whirl and bustle of the world. Only the deepest and most intimate
feelings break out in such moments. And here they have left their
monument—in a Latin name that science will go on coldly entering in its
catalogues for ages to come. It seems to me that this simple fact tells
us more of the character of this true-hearted man, in whom nothing human
was lacking, than long narratives could.
* * * * *
When the aged Sethe saw the break-up in 1806 of the State of Prussia, in
the invulnerability of which he had believed as a gospel, he sought
refuge in the comfort of work. “I succeeded in benumbing my mind: I
experienced in myself that hard work is a soothing balsam, co-operating
with our tardy healing force.” The grandson, wounded in a more terrible
way and cut to the very heart, tried the same remedy.
Thirty years afterwards, when crowns were prepared and speeches
delivered in honour of Haeckel’s sixtieth birthday, when the whole of
Jena fêted him as their own, and the veil fell from his marble bust in
the Zoological Institute, to which seven hundred of the best known names
in German and foreign science had contributed, the hero of it all went
back to that dark hour. “I thought at the time that I could not survive
the blow, thought my life was closed, and purposed to bring together all
the new ideas that Darwin’s theory of evolution had evoked in me in a
last great work. That was the origin, amid bitter struggles, of the
_Generelle Morphologie_. It was written and printed in less than a year.
I lived the life of a hermit, gave myself barely three or four hours
sleep a day, and worked all day and half the night. My habits were so
ascetic that I really wonder I am alive and well before you to-day.”
In his hour of collapse Haeckel sat down and wrote “the book of his
life.” There were only two alternatives for a book written in such
circumstances. It would be either very bad or very good. When a young
man in his thirties throws himself into a great effort of this kind and
writes a work that he conceives as a testament—a work in which he will
speak for the last time, but will say everything—it is a desperate test
of all that he has done in his three decades of life and is about to
give to the world. In this case the test succeeded beyond all
expectation.
The _General Morphology of Organisms_[2] was published in 1866, with the
sub-title: “General elements of the science of organic forms,
mechanically grounded on the theory of descent as reformed by Charles
Darwin.” It consists of two thick volumes of small print, containing
more than 1,200 pages. The preface is dated September 14, 1866. It is
now one of the most important works in the whole mental output of the
second half of the nineteenth century. In respect of method of
scientific research it is a landmark by which we may characterise and
appraise the whole half-century. For general biological classification
it inaugurates a new epoch, as had been done fifty years before by
Cuvier, and again fifty years earlier by Linné. What it did for zoology
in the narrow sense was thirty years afterwards summed up in one phrase
by a writer of acknowledged competence, Richard Hertwig: “Few works have
done as much towards raising the intellectual level of zoology.” Among
Haeckel’s own achievements, great and varied as they are, this work
occupies the highest place. Setting aside certain special pieces of
research, and regarding him mainly as a man of great ideas, we find his
whole programme in this work. The _History of Creation_, that has taken
his name far and wide over the globe beyond the frontiers of zoology, is
only an extract from this work. He put his heart in it. The others are
only the improved blood-vessels of his system of ideas, partly
duplications, partly simplifications. I do not say this either in blind
admiration or in criticism, but as the expression of a plain fact.
Posterity will turn to this work when, either in hostility or in
sympathy, it wishes to appreciate Haeckel.[3]
Footnote 2:
This work of Professor Haeckel’s has not been translated into English.
[Trans.]
Footnote 3:
Professor Huxley described the _General Morphology_ as “one of the
greatest scientific works ever published.” [Trans.]
His contemporaries did not accept the work without difficulty. It came
out without noise, exerted a tremendous influence in a quiet way, and at
last disappeared altogether from the bookshops. It is still attacked,
but has never been refuted. At libraries one finds, as I know from
experience, that it is always “out,” and therefore must be read
continually. It is found occasionally at second-hand booksellers; an
antiquarian price running to five pounds and more is put on it, after
forty years’ active production on the part of its author. At present you
could count on your fingers the German works that have this distinction
of being highly priced and out of print. One such is Vischer’s
_Æsthetics_, and another is the first edition of Gottfried Keller’s
_Green Henry_. Keller had threatened any one who ever attempted to
republish this first edition (afterwards modified but not improved by
him) that their hand would not rest quietly in the grave. But the price
of the work went up amongst antiquarians. I feel, in speaking of
Haeckel’s _General Morphology_, that I am describing a book which has
become so rare that one must treat it as something new, a codex that is
only accessible to a few. It is certainly not known to the general
reader.
Let me endeavour in a few words to give a general idea of the chief
contents of the work.
All the intellectual forces that had had any influence upon Haeckel now
concentrated for a supreme achievement. First of these was Goethe, who
supplied the title, “Morphology.” In its simplest signification
morphology is merely “the science of forms.” If I take houses,
furniture, statues, fishes, flowers, crystals, &c., and only regard and
describe their forms, I am a morphologist in the literal sense of the
word. But when Goethe invented the term he sought to give it a more
restricted application, writing in the style of earlier days, but
clearly enough, at Jena in 1807. We have, he says, natural objects
before us, especially living objects. We try to penetrate the secrets of
their nature and their action. We are not merely observers, but
philosophers. It is from this point of view that we approach the
subject. It appears to us that the best way to proceed is to separate
the various parts. Such a procedure seems calculated to take us very
far. Chemistry and anatomy are instances of this analytic kind of
research, and both are greatly esteemed and successful. But this method
has its limitations. “We can easily break up the living thing into its
elements, but we cannot put these together again and restore them to
life. We cannot do this in the case of many inorganic, to say nothing of
organic, bodies.” What are we to do? “Hence,” Goethe continues, “even
scientific men have at all times had an impulse to recognise living
things as such, to grasp connectedly their external visible and tangible
parts, and take these as indications of the inner life, and thus in a
sense to compass the whole in one glance.” “Hence we find at the
threshold of art and knowledge and science a number of attempts to
establish and elaborate a science that we may call _morphology_.”
Perhaps Goethe’s meaning can be realised best if one takes a great work
of art—say, the Venus of Milo—and imagines how these different kinds of
knowledge would deal with it. Purely analytic anatomy would dissolve the
superb artistic form into a rubbish-heap of bits of marble. Chemistry
would still further break up these bits of marble into the chemical
elements of which every block of marble is ultimately composed. The
“form” would disappear altogether. But in this case the form means—the
Venus of Milo. We see at once that we need another branch of science and
investigation besides anatomy and chemistry: we need a morphology, or
science of the complete form in which the block of marble is moulded
into the Venus of Milo. In the case of our work of art, morphology would
be identical with æsthetics, or at least with a branch of it. There can
be no doubt that the first and most imperative need for the
establishment of a special science of morphology arises from artistic
and æsthetic feelings. It is not without significance that it was
founded by the poet Goethe, and elaborated with such great success in
the nineteenth century by the born artist Haeckel. However, that does
not prevent the analogy of the Venus of Milo, which happens to be a
creation of human art, being applied equally to every individualised
form in nature, to every crystal, plant, and animal. Goethe himself
immediately transferred his morphology into the province of botany with
such vigour that the term is still regarded, in its narrower sense, as a
technical botanical expression. It extends, however, to the whole world
in so far as its contents come before us in “forms.” When Haeckel
adopted the term he deliberately restricted it, in harmony with the
general definition, by calling his work the “Morphology of Organisms,”
or the science of the forms of animals and plants.
But there was one danger in the conception of a morphology of animals
and plants, namely, the danger of taking it to mean a purely external
description: so many thousand species of plants, soberly described,
labelled, and numbered, a huge cabinet of stuffed skins, a herbarium of
hay. A whole scientific school had really taken it in this sense since
Goethe’s time; much as if one were to think æsthetics consisted simply
in forming an illustrated catalogue of all the art-treasures in the
world, a realistic catalogue in which the marble statues from the
Parthenon and the Moses of Michael Angelo would simply be given as
number so-and-so in class so-and-so.
Haeckel was preserved from this school by his more immediate masters, as
well as by Goethe himself; firstly by Johannes Müller, then by the
botanist Schleiden, finally by the influence of Gegenbaur. There was at
the time enough, and more than enough, of this external
museum-morphology. It was far from Haeckel’s intention to produce a new
compendium, in several volumes, of this kind of science of plants and
animals. His morphology was to be “general,” to have a broader range, be
a programme. As Richard Hertwig said very happily at a later date, he
saw his science, not as it then was, but as it _ought_ to be, in his
opinion.
The science of forms was to be in the fullest sense a “philosophy of
forms.” “Zoological philosophy” was the name given by the hapless
Lamarck, in France a century ago, to a work that appeared in the year
that Darwin was born, and anticipated his most advanced thoughts.
Haeckel, also, gave a new “philosophy of zoology and botany.” The title
embodies the magic formula that gave him courage to take up resolutely
once more the proscribed word, that seemed to have been scalded and
spoiled for ever in the witches’ cauldron of “natural philosophy”; it
spoke of the “theory of descent as reformed by Charles Darwin.” Two
sub-titles divided the work into two sections from the start. The first
part was, the critical elements of the mechanical science of the
developed forms of organisms (animal and plant); the second part was,
the same elements of the mechanical science of the developing forms of
organisms.
In these titles we see the decisive advance beyond Johannes Müller. As
Goethe had already declared, morphology as such can be formed into a
real and profound science. It will then not confine itself pedantically
to a registration of forms. It will compare them with each other, and
seek the hidden law in the straggling phenomena. It will mark out broad
lines that will enable the human mind to grasp its objects in all their
fulness. Johannes Müller had only been able to confirm that in the
narrower sphere of biology. This was the nerve that gave vitality to
zoology and botany, and made them a province of the mind in the higher
sense. But the question now was: which laws were detected, and in which
category of thought were they to be found? Müller had the theory, but
was weak on the practical side. There were the “forms” of animals and
plants. What was it that really connected them? What was the reality
that corresponded to the philosophic craving of the intelligence?
Müller’s next school, the generation immediately preceding Haeckel, that
of Du Bois-Reymond, Virchow, and many others, had apparently indicated
the solution. They had replaced Müller’s vague general conception of the
laws of morphology and life, which was undermined by older influences,
by a single great demand. We want to grasp nature as a unity. At one
point in nature we have reached deep and apparently fundamental
factors—in physics and chemistry and their plain natural laws or forces.
Now let us try, starting from the idea of unity and from the plainest of
all philosophical principles, that of proceeding from the known to the
unknown, to reduce the forms and phenomena of life to these natural laws
of chemistry and physics. Let us find out whether the whole form-world
of the animals and plants—in other words, the whole province of
morphology in the narrower sense—can be traced to the same natural laws
that we have in chemical and physical phenomena. The globe is the object
of chemistry and physics. Shall these few green or other-coloured things
that lie at the limit of the air, water, and rocks, a small minority in
nature, the things we call animals and plants, alone in the whole world
be exempt from the action of these laws? It is immaterial that Müller’s
best pupils, Du Bois in his later years and Virchow at an early date,
departed more or less from this consistent position of theirs into
philosophic and other sidepaths. The younger generation, to which
Haeckel belongs, that only came into direct touch with Müller in his
last years, heard no other gospel. What further advance was to be made?
In chemistry and physics they had before them the deep stratum that
yielded good mechanical laws. The first stage of physiology after
Müller, as we find it, for instance, under Du Bois-Reymond, yielded some
good indications for the organic. But was the whole of morphology to be
remodelled? Was the vast labyrinth of the thousands and thousands of
animal and plant forms in the museum to be reduced to mechanical laws,
corresponding to those of physics and chemistry, and be explained by
them?
Darwin brought salvation. Now that he had appeared, Haeckel felt that he
could begin to work. The hour and the man were come.
Darwin made it possible for him to raise morphology to a penetrative
science, equal to physics and chemistry, and so to make a step towards
the unity of our knowledge of a unified world. Hitherto the morphology
of the animals and plants had been in confusion. God, imagined in the
form of a higher man, had deliberately created the organic forms, the
palm, the moss, the turtle, and the man. He had constructed them on a
definite plan, as a man makes machines. Now, it appeared, the deeper
stratum was peeping out even here. Laws that had built the heavens and
the earth reached, by way of the Darwinian theories of selection and
adaptation, to the moss and palm, the turtle and man.
It was Haeckel’s peculiar distinction to take up this path as the right
one. It was then altogether new; to-day, even in the eyes of an
opponent, it has at least the solid and consistent support of a
considerable party. In later years, apart from open deserters from the
free and uncompromising pursuit of truth like Virchow, a school of
zoologists and botanists has been formed that will not recognise in
Darwinism a reduction of vital phenomena to the simple chemico-physical
laws of the rest of nature. They look upon it partly as inaccurate in
its allegations of fact, partly as a nebulous confusion, if not, as I
have already said, as a false mysticism or metaphysic. In the opinion of
these critics, whose own confused ideas very often leave little to be
desired in point of nebulosity, and who frequently try to drive out the
devil by means of the devil’s grandmother (a matter we cannot go into
here), Haeckel had made a great mistake in thinking that Darwinism would
solve the Du Bois-Virchow problem of reducing all living things to the
laws of lifeless matter. Even these, however, must candidly acknowledge
that in doing so he was the victim of his consistent and honourable
inquiry. At all events he must logically have seen the correct line at
that time as it is recognised to-day by this anti-Darwinian but
professedly mechanical school. His individual error can only have been
that he was deceived as to the true course of the line, and so clung to
Darwinism. However, we have said enough on this point.
Haeckel himself, at the time he was producing his greatest work, saw in
Darwin the absolute “open Sesame” to all the doors of philosophic
morphology. With this Sesame came an entirely new impulse, namely, to
write the natural history of the animal and plant form. It was just the
same as when æsthetics perceives a new world, a world that alone is
worthy of it, the moment it passes from the making of a mere catalogue
of the world’s art-treasures to the knowledge of even one single law of
artistic creation, in virtue of which one single work of art has been
actually built up.
It is impossible to begin with more general considerations than this
book does. The method of scientific research generally is explained in
order to give an idea of the new Darwinian morphology. With a calmness
that must have made most of the contemporary zoologists and botanists
shiver, the discredited idea of natural philosophy is restored from the
lumber-room. “All true science is philosophy, and all true philosophy is
science. And in this sense all true science is natural philosophy.”
The various periods in the development of morphology are coolly
schematised. These epochs are characterised by the vicissitudes of the
struggle between the simple description of forms in the animal and plant
worlds and the philosophic exposition of the laws that lie behind these
forms. In the eighteenth century, under Linné, there is a period of
purely external description and classification. It is succeeded in the
first third of the nineteenth century by a triumph of the philosophic
treatment of animal and plant forms. This increases with Goethe and
Lamarck, and grows into the older (and now generally abused) imaginative
natural philosophy. Then there is a general reaction; with Cuvier comes
the least philosophical of methods, though at the time it is a real
advance. While Linné only gave an external description of forms and
catalogued them, Cuvier’s epoch penetrated to the inner structure, the
inner world of forms, and thus rendered great service. The last and
greatest workers of the period, Müller, Schleiden, &c., give the signal
for a reaction in the hour of its chief triumph. Haeckel now follows
this up as “the element of fact in their ideas.” With Darwin he
inaugurates the fourth epoch, the triumph of natural philosophy for the
second time. But it is now far deeper and clearer; it embodies all the
good that preceded, all that Cuvier and his followers have done, without
the irresolution of earlier days. Now that we have studied the living
form in its innermost structure, as was never done before, in the
earliest stages of embryonic development in the ovum and womb, in the
past geological periods of the earth’s history, we will _think_ over
this form, think with all the means at our command, reason,
synthesis—even _imagination_, when it is necessary to press on to the
great final conclusion, a new synthesis of the defective positive data.
What does Johannes Müller say? “Imagination is an indispensable servant;
it is by means of it we make the combinations that lead to important
discoveries. The man of science needs, in harmonious co-operation, the
discriminating force of the analytic intelligence and the generalising
force of the synthetic imagination.” That is spoken from the depths of
Haeckel’s heart, and he drives it home.
Nothing is more amusing than to find Haeckel’s later opponents saying,
_apropos_ of any particular question, that his statement springs from
his “imagination,” as if it were something wholly unscientific that the
naturalist must shun like the pest; or again, that Haeckel here or there
falls a victim to the deadly enemy of all scientific research, natural
philosophy. It is pointed out to him as a great discovery which he must
approach in a proper penitential spirit—to him who has discussed these
matters so unequivocally in his first theoretical work.
As a fact, these methodological chapters in the first volume are as
clear as crystal. The titles will seem strange to the man who thinks he
can do without any philosophical instruction in zoology and botany, and
wants to hear only of cells, tissues, stalks, leaves, bones, scales, and
so on, in a general morphology. One chapter has the heading: “Empiricism
and Philosophy (Experience and Knowledge).” Another heading runs:
“Analysis and Synthesis.” Then there are: “Induction and Deduction,”
“Dogmatism and Criticism,” “Teleology and Causality (Vitalism and
Mechanism),” “Dualism and Monism.” The last three antithetic headings
are united under a general title as “Critique of Scientific Methods that
are Mutually Exclusive.” Such a title illumines the whole situation like
a flash of lightning. Many years afterwards Haeckel himself said of his
_General Morphology_ that it was a comprehensive and difficult work that
had found few readers. At least the whole of this first and most
difficult part of the book must be defended against the criticism of its
parent. If it is far from adequately appreciated to-day, especially by
professional philosophers, that is certainly not due to its style, which
is a model of clearness in the eyes of any one with the least
philosophical culture. The real evil was that people did not look to it
for instruction from the philosophical side. The title, “Morphology of
Organisms,” had a technical sound. The empty space between professional
philosophy and professional zoology is wide enough to-day, but it was
far wider thirty-four years ago. Books like Büchner’s superficial and
popular _Force and Matter_, or Haeckel’s own later work, the _History of
Creation_, that can only be regarded as a brief and incomplete popular
extract in comparison with the _General Morphology_, with all its
peculiar literary charm, stole into the philosophy of the time like
foxes with burning straw tied to their tails. Professional philosophers
have written whole libraries on them. The matter recalls a fundamental
defect in academic philosophy: it has little or no sympathy with real
scientific work; in fact, it studiously avoids such sympathy in the
consciousness of its own weakness. Hence it has, like every other layman
with general interests, to wait for attempts to popularise scientific
work before it can know what is going on in the serious camp. The man
who wants to-day to criticise the mechanical conception of nature should
first make himself acquainted with these chapters of the _Morphology_.
How many know the mere title of the work? How many even of those who
evince great hostility whenever Haeckel’s name is mentioned?
The book contains much more than the methodological introduction. This
only takes up the first hundred pages, but it contains the whole
programme. We start off, therefore, under full sail for a new epoch of
thought, for natural philosophy; but we must keep an alert mind. The
deeper task, that Darwin only gave the means of accomplishing, was to
reduce all living things, animal or vegetal, to the inorganic. The laws
of life must be merely certain complications of the simple laws that are
encountered directly in chemistry and physics, and rule throughout
nature. It must be one of the first aims of a general philosophic
morphology to open out a path in this direction.
The living and what is called the “dead” must be compared. Linné’s three
rigid kingdoms—animal, plant, and mineral—needed definitions in harmony
with the new ideas. Haeckel himself had discovered the “monera,” the
living particles of plasm that did not seem to have reached the stage of
the true cell. Here, clearly, was the lowest level of the living. At the
same time we reach the most complex specimen of the inorganic from the
morphological point of view—that is to say, the most interesting in its
individual form—the crystal. The differences begin to give way. What
marvellously similar functions! From the dead mother-water is built up,
purely by chemico-physical laws, the beautiful structure of the crystal.
From the lowest living particle of plasm without any special organs, as
we see in the radiolaria, are formed the beautiful siliceous frames that
Haeckel had collected in such quantities at Messina. Is it more than a
hair’s breadth to pass from one to the other? The deeper we go in the
study of living things, the slighter become the differences that
separate them from “dead matter.” On the other hand, the higher we go in
the structure of crystals, the more striking is the resemblance to the
living thing. Two chains of thought seem to be started. What we call
“dead” is really alive: what we call living is really subject to the
same laws as the “dead.” The solution is found in complete Monism.
Living and dead are not antithetic. Nature is one; though we see it in
different stages of development. We call one of them the crystal,
another the cell, or the moneron, or the protozoon; another the plant,
another the animal. Historically it all hangs together. The same laws
hold sway throughout. In framing my arbitrary definitions I can say
either that the dead is living, or that the living does not differ
essentially from the dead. In the chain of living things man comes from
the primitive cell, the moneron. This in its turn has developed from
something earlier—“naturally” developed. The very idea of life forces us
to seek the predecessors of the monera. Hence we speak of “spontaneous
generation,” as what was dead according to our ordinary use of language
has begun to live. In point of fact it is merely development of a
unified whole. There is no gap, no leap, no act that is not natural. The
dead and the living never were really antithetic.
The insistent statement that not only does the living approach the
inorganic, but the inorganic approaches the living, is quite
“Haeckelian.” The study of the “life” of crystals is one of the best
parts of the book. Later generations will appreciate it. We are much too
narrow to-day when we merely reflect that life, even the life of man,
can be traced by evolution down to what we call dead matter. We forget
that this “matter” is already high, since it potentially contains life,
and even man, the crown of life. Many people imagine that the derivation
of man from “dead matter” is equal to turning a king into a beggar. They
do not reflect that, on the other hand, a beggar is turned into a king.
When I say that life arose one day out of the inorganic, or that a
crystal was turned into a cell, my statement really involves the
complementary truth that the inorganic potentially contains life in
itself. Otherwise we have the old miracle over again of something being
produced out of nothing, in spite of our spontaneous generation. Haeckel
has always been clear on this point. His later studies of the soul of
the atom and the plastidule only carry out the absolutely logical
treatment of the question that we find in these chapters of the first
volume of the _Morphology_.
Incidentally the question is raised whether the plant or the animal was
evolved first. Animal and plant are, of course, not rigidly distinct
from each other. They are only the two great branches of the Darwinian
evolution of living forms, and are united at the bottom, however much
they diverge above. Gegenbaur had represented this years before (1860)
in a figure that Haeckel quotes in his _Monograph on the Radiolaria_ in
1862. The whole kingdom of living things must be conceived “as a
connected series, within which we find two lines diverging from a common
centre and representing a gradual differentiation and development of
organisation.” The terminal points of these lines (the highest plant and
the highest animal) are very different from each other, but the
difference gradually disappears as we go back towards the common centre,
and the lowest stages in each kingdom can hardly be distinguished from
each other. For these lowest stages Haeckel now carries out a plan that
very quickly forced itself on him.
He forms them into a new kingdom of life. To the animal and plant
kingdoms he adds the primitive realm of the beings that showed
unequivocal signs of the possession of life, yet were neither animals
nor plants. He gives them the name of “Protists.” To botany and zoology
is now added protistology.
The name “protists” (from _protiston_, the very first) is familiar to
every one in biology to-day. If protistology has not yet been securely
established as a special branch of science, that is due to the
circumstance that a strict limit cannot be determined on either the
plant or the animal side, so that the botanist encroaches on the
province at one point and the zoologist at another. But when we remember
that Haeckel’s protists include the well-known bacilli, on which whole
libraries are accumulating to-day, it is clear that the province must be
definitely marked off at some date in the near future, whether one
accepts Darwinism or no.
These important innovations in technical biology show very clearly how
sound and fruitful the new “natural philosophy” was. We have to go back
to the untenable and utterly impracticable systems of Hegel, Schelling,
and Steffen, which were immediately rejected as the trifling of
_dilettanti_, or even to much that the admirable Oken did on the
scientific side, if we would measure the whole distance between what
people understood in the sixties by “natural philosophy” and the real
reformed philosophy that Haeckel gave to the world. This becomes clearer
at every step we take in his work.
The first book has determined the method that leads to morphology, the
science of forms. The second has ranged the organic forms—protists,
plants, and animals—over against the inorganic or “dead” forms, as far
as this is possible from the new evolutionary point of view. We feel
that the third book will pass on to Darwin, and explain the world of
organic forms by the Darwinian laws of evolution. Then the programme
would be carried out in its main features.
But Haeckel writes two whole books before he comes to this, and they
are, perhaps, the most characteristic in the work. He only “adopted” the
theory of evolution in the sense that he applied it far more thoroughly
than Darwin to practical problems. In these two books he is entirely
himself. They are, at the same time, the most difficult in the work.
Even to-day they place him on a lofty and lonely height apart from the
great and strenuous controversy over Darwinism. I believe that the time
will yet come that will fully appreciate these books. Through them
Haeckel will play a part in philosophy of which we have at present no
prevision.
There is a word that is inseparable from the word “form”—individuality.
Morphology, which does not analyse, but studies the form-unities as a
whole in the sense of Goethe’s definition, comes from the nature of
things to deal with the individual. In our artistic illustration the
Venus of Milo, as a form-unity, is an æsthetic individuality. When its
form is destroyed, its individuality perishes.
Let us apply this to any one of the higher plants or animals. Take a
turtle, for instance. A definite individual embodies the definite form
to which I give the name. This form as such is entirely lost if I cut up
the turtle until it is unrecognisable. The limit of morphological study
seems to be, just as in the case of the Venus of Milo, the integrity of
the individual turtle. Yet in the living turtle we find an enormous
difference.
If I grind the Venus of Milo into dust, I am at once in a totally
different world with this dust. I am amongst the raw material of nature,
untouched by æsthetic influence. From this calcareous powder I can, in
reality or imagination, pass on to the world of crystals, molecules, and
atoms. In that case I shall have done with æsthetic morphology. I come
to the morphology of the inorganic, a very different branch. What do we
find in the case of the living turtle?
It is true that I can break up the turtle into simple chemical
substances. In that case I make the same transition; I abandon organic
morphology, and pass, with the same _salto mortale_ as in the case of
the Venus of Milo, to the lower science of inorganic morphology.
But when I examine the structure of the living individual turtle before
me I notice a special feature. Let us suppose that I break up the Venus
of Milo only to a certain degree; or, with less vandalism, I do not
break it up, but light up its inner structure to some extent by a sort
of Röntgen-ray apparatus. And suppose I found that this one æsthetic
individuality is made up of millions of much smaller and æsthetically
finer and more unified images. I do not mean of millions of repetitions
of the large Venus in miniature, but of real and unmistakable little
works of art, each of which, regarded separately and without any injury
to its narrower individuality, might be just as excellent a subject for
æsthetic examination as the whole Venus.
This is, of course, nonsense as regards the Venus of Milo. There is
nothing of the kind in it. I have given the paradoxical supposition
merely for the purpose of showing what we really find in the case of the
turtle.
When the organic individual turtle is closely studied it breaks up first
into so many _simpler_ organic individuals, which undoubtedly belong as
such to the province of organic morphology. They are the _cells_. The
theory of Schleiden, Schwann, and Virchow here comes into direct touch
with morphology. Every higher animal or plant has its own individuality;
and within this individuality there is a conglomerate, a community, or a
state, of individuals of a lower order, that have their own life and
their corresponding individual life-form. Man himself, the highest of
animals, is a cell-state. So Virchow taught. Each one of us is an
individual, and as such an object of morphology. The cell, each single
cell in each of us, is also an individual, and as such is equally an
object of morphology. Hence it is the task of the morphology of
organisms, not only to describe these higher individualities as such,
but also to look on them as glass-houses, as it were, with so many
shelves, divisions, and smaller houses within of a lower rank. These
internal arrangements have to be described, piece by piece, with the
same fidelity.
This will probably suffice to convey a general idea of the subject.
Clearly, the great work that ought to form the general part of
morphology at this point was the precise determination of all these
various layers of individuality that are found in the animals, plants,
and protists, and, as we rise upward, enter into more and more complex
relations to each other.
The difference between, say, a turtle or a man and the cell which
combines in its millions to form them is not the only one. Between them
we seemed to find individualised, or almost individualised, links. Think
of the idea of an organ. What is my heart? It is made of a number of
cell-individuals, like my whole frame. But these cells form a sort of
intermediate individuality in me. We may go further. What is a segment
of a worm? What is an arm of a star-fish? They have so much independence
that they can continue to live, rapidly producing new cells and forming
a new worm or star-fish of the higher individual type, if they are cut
off. The arrangement is still more difficult in the case of the plant.
Where in their case shall we find the stages of individuality that
correspond to the animal-human? The cells are distinct in both cases.
The individual plant-cell corresponds to the individual animal-cell. But
what is there in the plant that corresponds to _me_, as the animal-human
multicellular individual? Does the oak-tree, for instance? Certainly,
the oak is an individual. But it seems that it is the single sprout of
it that corresponds to what I am. What is the relation of the tree to
this sprout?
Here our ideas grow dim and confused. We human individuals unite to form
certain higher communities. The word “social” reminds us of the fact:
then we have the nation, the race, humanity. At least the earlier of
these stages certainly perform various combined functions, and are
understood to form, or wish to form, new individuals. We speak of the
social organism, the body of the people, the soul of the people, and so
on.
We see that still more clearly in the case of the animals about us.
Individuals, that correspond to our conception of an individual man,
combine and form stocks and colonies, with division of labour. We find
this in the medusæ, corals, anemones, tunicates, and vermalians. One of
these animal stocks, to which our human social combinations only
correspond in a much wider sense, gives us a stage that is represented
by the tree in the plant-world. Infinite perspectives open out, and also
infinite complications. Infinite problems spring up for morphology to
deal with; it must make its way through the labyrinth of these
complicated types of individualisation.
The matter is still more intricate if I begin at the bottom of the
biological series and proceed upwards. I, man, am an individual of a
certain stage in my own collective activity. It is true that I am made
up of millions of cell-individuals, but when we look at the whole these
are merely elementary units. But take a being from the protist-world
that is too lowly to be either animal or plant. In respect of its whole
activity it is an individual just as much as I am, and therefore in this
regard at the same stage as I. At the same time it consists of a single
cell. The distinction in me between unit and whole does not exist in it.
Its unit is the whole. It would seem a Sisyphean task to reduce all this
to a system.
Yet that is just what Haeckel has done.
With crystalline clearness he separates and reunites and arranges
everything, from the primitive organic individual, that is not yet a
true cell—the monera he had himself discovered—upward. Organic
morphology begins with them as its first object, the first complete
individuality, the first “form.” All that lies below it is beyond the
province of morphology. The last conceivable organic individuality is,
perhaps, the atom; and that is not the concern of morphology. We start
from the organic. Above the pre-cellular individuals and the true cells
the next form-unities are the organs. Above the organs, after a few
subtle intermediate stages, are the “persons.” Thus a new word is given
to what we have hitherto conventionally called an “individual,” when we
wanted to denote a turtle, a bird, a man, or an higher animal as a
whole. To this corresponds in the plant the sprout. The stage above the
“person” is the “stock.” We might also call it the social individual; in
the plant-world it is the tree, in the coral the coral-stock, in the
human case the social combination of a number of men for common action.
We are reminded of Virchow’s speech, and how “consciousness” was dragged
into the debate on the cell-state. What psychological perspectives are
opened out by this doctrine of individuality! Each form-unity, each
single individuality in the series, with a soul! Souls combining for
common action, and forming higher psychic unities! There is no detail in
Haeckel’s whole life-work in which he speaks more boldly and freely and
philosophically than he does here. His lucid treatment raises to a
higher stage a philosophic question that has occupied thinkers for ages.
That is the third book. The fourth takes up a different subject. Let us
adopt in organic morphology this wonderful theory of individuality, the
theory of stages within the form. Then let us turn to consider
impartially the vast multitude of living forms. How can we now arrange
this infinite confusion by merely looking at it? Artificial
classification has attempted it a hundred times, and always without
success. On this side there is only one way to proceed—the mathematical.
I study them with strictly mathematical figures. I determine their axes,
and the mathematical aspects of their forms. Possibly that will give a
practical result; the only kind of artificial system that can be
accommodated with the Darwinian theory, and perhaps render it assistance
by the sharpness of its lines. Does it answer? Take a crystal, a
specimen from inorganic morphology. The description of it is susceptible
of a strictly mathematical form. Now take a star-fish, a worm, a human
being. We find that even these organic structures have a mysterious
relation at bottom to certain mathematical, stereometric forms. We might
almost say, to certain forms of human thought. Everything in the organic
world is in a state of flux. But through the whole moving stream we can
trace the outline of one stable element, something like a mathematical
idea. A sort of Platonism of the living forms vaguely takes shape.
Haeckel speaks of lines, axes, circles, radii, and all kinds of rhythmic
structures. It does seem that the countless individual forms of living
things fit into a scheme of a limited number of mathematical forms.
Strictly speaking this is not a real morphology of living things. We
only find these clear and rigid forms schematically in the wild
profusion of forms of the protists, plants, and animals. They are only a
reminiscence of the laws of the purely inorganic, which the eye of the
observer just detects as the lowest stratum. Hence Haeckel calls this
section the “promorphology” of organisms.
It is true that this section, which essays to compress all living things
into a very simple scheme, is the hardest to read in the whole work. A
number of strange and difficult words have to be invented for this
stereometric scheme to which he would reduce the animal and plant forms.
Haeckel himself declared, twenty years afterwards (in the second part of
the _Monograph on the Radiolaria_), that this stereometry of organic
forms had found little favour in biology “especially on account of the
difficult and complicated nomenclature.” But he had complete confidence
as to the substance of it, even after so great a lapse of time.
In point of fact we have here, it seems to me, a gigantic preparatory
work, not so much for the strict purpose of classification, as for a
real philosophy of botany and zoology that will be founded some day.
This recurrence of sharp stereometric structures, not only in the
crystal, but also, if less clearly, in the biological world, will one
day prove an important source of knowledge, in a sense that is not even
clear in Haeckel himself.
We are already entering upon a period that has a glimpse of the truth
that the deepest power of Beethoven’s music, or Goethe’s poetry, or
Raphael’s painting, or Michael Angelo’s sculpture is a mysterious
revelation of the most subtle mathematical relations and
effects—produced without conscious perception of these relations, though
a human mind is at work in them. In spite of all our “consciousness,”
the obscure intuitive power at work in these human artistic achievements
differs very little from the curious force with which a radiolarian
builds up its little house in the deep-sea or a caseworm fits on its
fine, rhythmic, snail-like coat. In both we have the same profound,
crystal-like constructive power that brought forth the wings of the
butterfly, the feathers of the bird, the bodily frame of all the animals
and plants, that harmonises so well with strict mathematical forms. In
Beethoven and Raphael it is not more conscious or unconscious, not
clearer or vaguer, not more mystical or more natural, than in the
poorest worm or the microscopically small radiolarian. The æsthetics of
the twentieth century will take up these ideas.
* * * * *
[Illustration:
HAECKEL’S VILLA AT JENA.
]
It is a great work. How few there are in the whole of the nineteenth
century that show the wealth of ideas we find in the first volume
alone.[4] And this is only one volume. We have as yet said nothing of
the idea that is of the greatest consequence in connection with
Haeckel’s own development. He was a Darwinian from 1862 onwards. After
1866 and the publication of the _General Morphology_ we find him
dominated in all his work by one single idea from the Darwinian group.
He brought this idea so effectively to the front, improved and developed
it so assiduously, and applied it in so many ways, that it has come to
be regarded as his own most characteristic work. It is inseparable from
his name. Whatever the future may be, wherever Haeckel’s name is uttered
people will add the phrase that was made peculiarly his after 1866, that
colours and pervades all his works—technical, popular, polemical, or
philosophical—as much as the word “Monism.” It is the phrase: the
biogenetic law.
Footnote 4:
The reader may be interested to know that Haeckel gives a popular
summary of his early work on individuality and on the mathematical
types of organisms in a more recent work. This has been translated
into English with the title _The Wonders of Life_. The two chapters
that deal with these questions are omitted from the abridged cheap
edition. [Trans.]
Here and there even in the first volume of the _Morphology_ a note is
struck that the reader cannot clearly understand. It increases in the
second volume until it dominates the whole book.
The phrase is known far and wide to-day. This is partly due to Haeckel’s
own insistence on it, but perhaps still more to the real value of the
idea itself. It crops up in a hundred different fields—psychology,
ethics, philosophy, even in art and æsthetics. I have been able to trace
it even into modern mysticism. For the moment I will only point out that
it has been attacked and misstated with real fanaticism, in spite of the
splendid and perfectly clear account of it that Haeckel has given.
The proper place to read of it is, as I said, the second volume of the
_Morphology_. This volume has to give an account of the evolution of
organic forms. What is given rather casually, almost Socratically, in
Darwin is now developed into a number of strict laws. This method of
expounding more or less hypothetical, new, and insecure ideas in the
form of laws has since been frequently attacked. Some have been led by
it to take the ideas as so many dogmas, and even to learn the laws by
heart as if they were texts in Scripture. Others have then laid the
blame of this dogmatic interpretation on Haeckel himself. It is quite
true that there was the possibility of a misunderstanding. People do not
always think for themselves, and the statement of a proposition in the
form of a law may prove a pitfall for them. The blind learning of them
by heart is always mischievous. On the other hand, it might be urged
that the statement of the ideas in this bald way affords the best
opportunity for a thorough and rational criticism of them, precisely
because they give such pregnant expression to the writer’s meaning. I do
not find that order and strict logical definitions have ever done any
harm of themselves, whatever it is that is put in order and defined. On
the contrary. People must confuse order sometimes with real dogmatism.
Of this there is not a word in the whole book, while at an important
juncture the reader is actually warned to be on his guard against undue
pressure. “In this,” we read in the twentieth chapter, “we do not wish
to draw up a body of laws of organic morphology, but to give hints and
suggestions for drawing them up. A science that is yet only in its
cradle, like the morphology of organisms, will have many important
changes to undergo before it can venture to claim for its general
propositions the rank of absolute and unexceptionable natural laws.”
However that may be, it was in this provisional definition of laws that
the famous biogenetic law first took shape, and with it a spirit entered
into Darwinism in the narrower sense that was never again detached from
its master, Haeckel.
Let us once more take a simple illustration from facts. Take a green
aquatic frog and a fish, say a pike.
Both of them have a solid vertebral column in their frames, and
therefore both must be classed amongst the vertebrates. But within the
limits of this group they differ very considerably from each other. The
frog has four well-developed legs, its body terminates in a tail, and it
breathes by means of lungs, like a bird, a dog, or a human being. The
fish has fins, it swims in the water by means of these fins and its long
rudder-like tail, and it breathes the air contained in the water by
means of gills. When we arrange the vertebrates in a series, with man at
their head, it is perfectly clear that the frog stands higher than the
fish in regard to its whole structure. It is lower than the lizard, the
bird, or the mammal, but at the same time it is a little nearer to these
three than the fish is. That was recognised long ago by Linné, who
assigned them a corresponding rank. The fishes are the lowest group of
the vertebrates; the frogs belong to the group immediately above them.
Now let us see how one of these frogs is developed to-day. The frogs are
oviparous (egg-laying) animals. The mother frog lays her eggs in the
water, and in the ordinary course of nature a new little frog develops
from each of these eggs. But the object that develops from them is
altogether different from the adult frog.
This object is the familiar tadpole. At first it has no legs, but it has
a long oar-like tail, with which it can make its way briskly in the
water. It breathes in the water by means of gills just like a fish. It
is only when the tadpole grows four legs, loses its tail, closes up the
gills at its throat, and begins to breathe by the mouth and lungs
instead, that it becomes a real frog. There can be no doubt whatever
that the tadpole is very much more like the fish in all the most
important particulars than the frog. Between the frog-egg and the frog
itself we have a stage of development in each individual case of which
we might almost say that the young frog has first to turn into a fish
before it can become a frog.
How are we to explain this?
At first people supposed something like the following: All beings in
nature are admirably adapted to their environment and their
life-conditions. Whatever be the explanation of it, it is a simple fact.
Now, the frog lays its eggs in the water. The young ones develop from
these eggs, and find themselves in the water. The most practical
adaptation for them is to swim about by means of a tail and breathe by
means of gills like the fish. They do not reach land until later, and
they creep on to it and have an equipment of the opposite character,
with legs and lungs.
But this explanation throws no light on the question why the frog lays
its eggs in the water. However, there might be some utility or other,
some need for protection, for instance, in that. Let us take a few other
cases.
There are several species of tree-frogs, and toads, and closely related
amphibia like the salamanders, that do not lay their eggs in the water.
Some of them bury them in folds of their own external skin, others (such
as the Alpine salamander) retain them within the mother’s body, as the
mammals do. The young animals develop there from the eggs. Even there,
however, where there is no question of aquatic life, the young frogs,
toads, and salamanders first assume the fish-form. The young frogs and
toads have fin-like tails, and all of them have gills. There seems to be
some _internal_ law of development that forces the frog and its
relatives to pass through the fish-stage in their individual evolution
even when there is no trace whatever of any external utility.
Now let us examine the matter as Darwinians and believers in evolution.
There are reasons on every hand for believing that the frogs and
salamanders, which now stand higher in classification than the fishes,
were developed from the fishes in earlier ages in the course of
progressive evolution. Once upon a time they were fishes. If that is so,
the curious phenomenon we have been considering really means that each
young frog resembles its _fish-ancestors_. In each case to-day the
frog’s egg first produces the earlier or ancestral stage, the fish. It
then develops rapidly into a frog. In other words, the individual
development recapitulates an important chapter of the earlier history of
the whole race of frogs. Putting this in the form of a law, it runs:
each new individual must, in its development, pass rapidly through the
form of its parents’ ancestors before it assumes the parent form itself.
If a new individual frog is to be developed, and if the ancestors of the
whole frog-stem were fishes, the first thing to develop from the frog’s
egg will be a fish, and it will only later assume the form of a frog.
That is a simple and pictorial outline of what we mean when we speak of
“the biogenetic law.” We need, of course, much more than the one
frog-fish fact before we can erect it into a law. But we have only to
look round us, and we find similar phenomena as common as pebbles.
Let us bear in mind that evolution proceeded from certain amphibia to
the lizards, and from these to the birds and mammals. That is a long
journey, but we have no alternative. If the amphibia (such as the frog
and the salamander) descend from the fishes, all the higher classes up
to man himself must also have done so. Hence the law must have
transmitted even to ourselves this ancestral form of the gill-breathing
fish.
What a mad idea, many will say; that man should at one time be a tadpole
like the frog! And yet—there’s no help in prayer, as Falstaff said—even
the human germ or embryo passes through a stage in the womb at which it
shows the outline of gills on the throat just like a fish. It is the
same with the dog, the horse, the kangaroo, the duck-mole, the bird, the
crocodile, the turtle, the lizard; they all have the same structure. Nor
is this an isolated fact. From the fish was evolved the amphibian; from
this came the lizard; from the lizard, on Darwinian principles, the
bird. The lizard has solid teeth in its mouth; the bird has no teeth in
its beak. That is to say, it has none _to-day_; but it had when it was a
lizard. Here, then, we have an intermediate stage between the fish and
the bird. We must expect that the bird-embryo in the egg will show some
trace of it. As a matter of fact it does so. When we examine young
parrots in the egg we find that they have teeth in their mouths before
the bill is formed. When the fact was first discovered, the real
intermediate form between the lizard and the bird was not known. It was
afterwards discovered at Solenhofen in a fossil impression from the
Jurassic period. This was the archeopteryx, which had feathers like a
real bird, and yet had teeth in its mouth like the lizard when it lived
on earth. The instance is instructive in two ways. In the first place it
shows that we were quite justified in drawing our conclusions as to the
past from the bird’s embryonic form, even if the true transitional form
between the lizard and the bird were never discovered at all. In the
second place, we see in the young bird in the egg the reproduction of
two consecutive ancestral stages: one in the fish-gills, the other in
the lizard-like teeth. Once the law is admitted, there can be nothing
strange in this. If _one_ ancestral stage, that of the fish, is
reproduced in the young animal belonging to a higher group, why not
several?—why not all of them? No doubt the ancestral series of the
higher forms is of enormous length. What an immense number of stages
there must have been before the fish! And then we have still the
amphibian, the lizard, and the bird or mammal, up to man.
Why should not the law run: the whole ancestral series must be
reproduced in the development of each individual organism? We are now in
a position to see the whole bearing of Haeckel’s idea, and at the same
time to appreciate his careful restrictions of it.
First, let us see a little of the history of the matter. In the first
third of the nineteenth century a number of pre-Darwinian ideas of
evolution flitted about like ghosts in natural philosophy, as I have
already said. The evolutionary ideas of Goethe and Lamarck are well
known to-day. Another thinker of great influence was Lorentz Oken, who
established the custom of holding scientific congresses. Oken had been
constantly occupied with embryology, the science of the development of
the individual organism. He was at all events acquainted with all that
was known at the time on the subject. I open an old volume, wretchedly
printed on blotting-paper, of Oken’s _General Natural History for all
Readers_ (1833), and turn to a passage in the fourth volume (the first
to be issued) on page 470.
We read that the caterpillar of the butterfly resembles the animal form
at a stage of development that lies below the insect—the worm. Oken
says: “There is no doubt that we have here a striking resemblance, and
one that justifies us in thinking that the development in the ovum is
merely a repetition of the story of the creation of the animal groups.”
Oken was quite aware that the chick in the egg had gill-slits like the
fish. He bases his idea on that fact. He was very close indeed to the
theory that Haeckel has so wonderfully elaborated. However, he was
greeted with laughter. His theory was treated as an absurdity from 1833
to 1866. It cannot be denied that he was himself partly to blame for
this. Oken made two serious mistakes. On both points Haeckel is
perfectly clear and sound. Moreover, the theory of natural evolution
that made it possible for us to speak of “ancestors” was still a
Cinderella in the days of Oken. No sooner was it rehabilitated than the
principle of the old theory of embryonic forms returned once more.
Darwin himself at once appealed to it, but it was reserved for Haeckel
to develop its full importance. He corrected it in two particulars. Oken
and his admirers had made an unfortunate mistake. They believed in a
genealogical tree of all living things, but they conceived it on the
lines of the old classification. Linné had enumerated in succession:
mammals, birds, amphibia, fishes, insects, and worms. He put them in one
straight line, which is certainly the best arrangement for general
purposes. But when Oken came with the idea of natural evolution, he at
once took this series as the outline of a genealogical tree. The mammals
descended from the birds; the fishes from the insects; and so on. If
that were really the case, the highest animals would be expected to
reproduce all the animal and plant stages in the course of their
embryonic development, on the lines of the theory. The human being would
have to be, successively, not only a lizard and a fish, but even a bird,
a beetle, a crab, and so on. This was by no means borne out by the
facts, and so the theory seemed to be discredited.
Now let us glance at Haeckel’s genealogical tables. We find eight of
them, artistically drawn, at the end of the second volume. The
“genealogical tree” is given in the form of a branching tree, or as a
huge forest-like growth of stems some of which only meet in the ultimate
roots. There is no trace in Haeckel’s designs of the sort of
Eiffel-Tower arrangement that the Linnean system involved. At the bottom
we find the protists, the most primitive forms of life. From this point
two parallel stems diverge, that of the animals and that of the plants;
they never touch each other after this point, and so cannot be expected
to be reproduced in the embryonic forms. Then the animal stem is split
up almost at the root into at least five independent branches, each of
which pursues its separate line of development. One culminates in the
insects, above the worms and the crustacea. A totally independent stem
issues in the vertebrates, and this in turn breaks into many different
branches. Beyond the lizards, for instance, we find the development of
the mammals and birds, which run on as separate and parallel lines. It
was mere nonsense to expect a mammal in its embryonic development to
assume the form of a bird, or a crab, or a beetle, or a mussel, or a
medusa, even if the biogenetic law were established ten times over.
The second mistake made by Oken was to declare that, whatever it cost,
the law must be observed everywhere. He examined the butterfly. It
passed through two curious embryonic stages: first the caterpillar, then
the pupa. The caterpillar corresponded to the worm; that might be
plausibly contended. But the pupa also must stand for something. Between
the worm and the insect in classification was the crustacean. It had a
hard shell: so had the pupa. Consequently, the pupa is a reproduction of
the crustacea-stage. Such were the bold chess-moves of the older
theorist.
Haeckel first established that there was such a thing as the biogenetic
law. There is a fundamental norm, which is made clear to us in
embryology and can at the same time (remember the instance of the
lizard-like teeth in the bird-embryo) give us most wonderful suggestions
as to the line of ancestral development. But it has certain limitations,
as we will now show.
The adaptations in the sense of the Darwinian laws have affected the
animal’s embryonic life more and more, the higher the tree of life grew.
The long recapitulation of the ancestral stages often came into conflict
with the young individual’s need for protection. The result was that the
biogenetic law found itself restricted by the Darwinian laws of
adaptation. The too lengthy succession of ancestral portraits was
abbreviated and compressed. Whole stages of embryonic or larval
development were interpolated that had nothing to do with these
ancestral portraits, but were destined for the protection of the fœtus.
The butterfly-pupa is really an instructive instance of this
description. It does not reproduce a crab-stage, nor has there been any
stage in the ancestry of the butterfly when they lived throughout life
in pupa-houses. The pupa is simply a later adaptation in the development
of the butterfly, a protective stage in which it accomplishes the
transition from the caterpillar-form in much the same way as the young
bird develops under the protection of the hard egg-shell. Thus only a
faint and shadowy trace has been left of the real ancestral forms,
though this trace is an extremely instructive one. But we must not
expect the impossible from it. In this way our naked and crude
biogenetic law assumes a more finished and scientific form: the
embryonic development of the individual is a condensed, abbreviated, and
to some extent modified epitome of the evolutionary history of its
ancestors. That is more modest, but it is a correct expression of the
facts. The essential point of the older idea was not in itself wrong;
all that was done was to explain the gaps, and leaps, and contradictions
in it.
Now that Oken’s share in the theory has been properly appreciated, we
may notice another little historical detail. In the period immediately
after his time these ideas were ridiculed by men of science, great and
small, but they were not exactly “done to death.” Agassiz, the most
pronounced creationist and dualist of all the nineteenth-century
zoologists, expounded them occasionally as a curious instance of the
divine action. In fact, he looked upon the whole of zoology as a mystic
cabinet of curiosities—the more curious the better. Thus he came to play
with this idea and confirm it, but merely took it at first as a fine
figure of speech. Agassiz is a tragical form. He survived Darwin, much
in the same way that many an elegant _mot-de-salon_ on the rights of man
survived the French Revolution. Suddenly the whole structure of his
ideas seemed to fall about him. Where he had played with roses, he now
found torches. He reeled like a smitten man, and cried out against the
horrid monsters that brought him pain and bitterness. His anxiety began
with Darwin, even as regarded the question of the embryo. But there was
another, a man far away in South America, that increased it—Fritz
Müller.
Born in 1822, one of the finest pioneers in zoological work, Fritz
Müller had wished to become a higher teacher, but had abandoned his plan
on account of the oath that had to be taken by every servant of the
State. In 1849 he wrote to the Ministry requesting that he might be
allowed to dispense with the formula “So help me God, through Jesus
Christ.” Meeting with a refusal, he went to South America, and began a
solitary life as a student in the primitive forest, and sought to
accumulate valuable zoological material. Darwin called him “the king of
observers.” In 1864 he published an essay of ninety-four pages with the
title _For Darwin_. He revived and improved the old idea of Oken’s and
made fresh contributions to the natural history of the crustacea that
were literally stupefying. We may say that the point that he believed he
had established, in virtue of the law, in regard to the genealogical
tree of the crustacea, was afterwards, with apparent justice, called
into question, even by supporters of the law such as Arnold Lang. That,
however, did not diminish the extent of his influence at the time.
Haeckel has generously acknowledged how strongly he felt that influence
himself. Nevertheless all that has been said about Haeckel’s priority in
fully applying and shaping the law, and in its final formulation, is
perfectly correct.
When Haeckel had massed his material he had first to create the
necessary terms for arranging it distinctly. In the language of the old
legend, he called the day day, and the night. To the story of ancestral
development, or the evolution of the stem, he gave the name of
_phylogeny_, or stem-history (_phylon_ = stem). The word circulates very
widely to-day. The story of the development of the individual until it
reaches maturity was then called _ontogeny_ (_on_ = being), which
coincides generally with embryology (though it may also include the
growth of the child). The law then ran: Ontogeny is an abbreviated and
frequently disarranged epitome of phylogeny. Special attention was drawn
to the qualifications “abbreviated” and “disarranged.”
Here again two fresh names were invented. In so far as the embryonic
development is a true recapitulation of the stem-history, it is called
_palingenesis_, or repetition of the ancestral traits. When the
development is altered by new adaptations it is called _cenogenesis_,
“foreign” or “disturbing” development.
It has been objected by small-minded critics that Haeckel forces nature
to mar its own work. The real meaning is quite clear if we bear in mind
the blunder of Oken. In this case “disturbed development” is merely an
expression of the fact that the laws we invent are ideal forms, and not
always convenient realities. We learn by heart that the earth is a
globe, and its orbit is an ellipse. Neither of the two propositions is
strictly accurate; no mathematical figure even has objective reality. By
the sheer attraction of the water of the ocean to the continents the
earth has an irregularity of shape that it is barely possible to express
in words. To call the path of the earth round the sun, constantly
altering as it does, and still further complicated by the sun’s own
movement, a real ellipse is the greatest nonsense conceivable.
In this sense every natural law is subject to disturbances, though these
in turn are the outcome of natural laws. If we do not cavil over the
name, we find that the idea it stands for is of the greatest consequence
for any further use of the biogenetic law. Unless it is borne in mind,
the law, especially in the hands of the inexpert, falls into hopeless
confusion. We read so often that the ancestral history is identical with
the embryonic development. The one is a recapitulation of the other.
This supposed law is then applied in psychology, æsthetics, and many
other directions. If it succeeds, there is jubilation. If it does not
succeed (as it does not in a thousand cases), the whole blame is thrown
on Haeckel. People discover that “the biogenetic law breaks down here,”
and they throw over Darwinism altogether.
The second volume of the _Morphology_ is the standing palladium against
all this nonsense. It marks off the real readers and followers of
Haeckel from the superficial talkers who run after him because he is
famous, and will leave him unscrupulously for any other celebrity of the
hour.
The book must be read. Even in this second volume an incredible amount
of matter is compressed. An introduction, consisting of a hundred and
sixty pages of small type, gives us an idea of the new system. This is
the first scheme of a real “natural classification” of living things.
From this we pass to special morphology. But this fearless sketch of the
specialised genealogical tree, according to the new ideas, puts general
morphology in its true light. We are made to feel that it is not all
mere theory. To-morrow—nay, to-day—the whole practice of zoology and
botany will have to be remodelled on the new principles. Off with the
roof of the ark! The whole museum must be cleared out. We want new
divisions, new labels. The old controversy between the Nominalists and
the Realists seemed to have come to life once more. How students had
played with the word “affinity” as a symbol. The lemurs were “related”
to the apes, and to other groups of mammals. The star-fishes were
related to the sea-urchins, to the encrinites. The word had, in fact,
led to a certain amount of arrangement; the stuffed or dried or
preserved specimens in the museum were placed side by side. Suddenly the
whole thing became a reality. The things that were “related” to each
other had really been connected historically in earlier ages. The lemurs
were the progenitors of the apes. Behind them were a series of other
mammals. Star-fishes, sea-urchins, and encrinites, formed a definite
branch of the great tree, and were historically connected; not
symbolically, but in a real extinct common ancestor.
It was a vast work. A single man had at first the whole kingdom in his
hands, had to reject the old lines of demarcation and create new ones.
There was a certain advantage at the time. Since Cuvier’s time an
immense quantity of new discoveries had accumulated for the construction
of a system of living things. Müller, Siebold, Leuckart, Vogt, and many
others, had done a great deal of preparatory work. All this was of great
assistance to the man who now came forward with courage and a talent for
organisation. Nevertheless it needed real genius, together with almost
boundless knowledge, to accomplish the task. We must remember how
reactionary (even apart from the question of evolution) was the
systematic work of distinguished and assuredly learned zoologists like
Giebel at that time; they worked on in a humdrum way as if the more
advanced students did not exist. How different it has all become since
Haeckel’s thorough reform of classification! We are astounded to-day at
the skill with which he drew lines in his very first sketch that were so
near to the permanent truth. I need only point to the new scheme of the
classification of the vertebrates. A good deal of his work was, of
course, bound to be defective, because the facts were not yet known; for
instance, in fixing the point at which the vertebrates may have evolved
from the invertebrates. It was not until a year later that the discovery
of the embryonic development of the ascidia by Kowalewsky threw light on
this. Again, there was the solution of the problem of the ultimate
root-connection of the great parallel animal stems. In this matter
Haeckel himself brought illumination by his gastræa-theory.
On the whole this systematic introduction to the second volume would
have sufficed of itself to secure for Haeckel a prominent position in
the history of zoology and botany. He himself was chiefly proud of the
fact that it was the first natural-philosophical system on the new lines
to meet the rigorous demands of academic science, and indeed to
revolutionise academic science. This enhances his complete triumph in
the last two books of the volume. First man is introduced, with absolute
clearness and decisiveness, into the system of evolved natural beings,
as crown of the animal world, but subject to the same laws as the
animal: a vertebrate, a mammal, whose nearest relatives are the
anthropoid apes. Thus at last the “system of nature” was complete. It
embodied the unity of nature. It formed the framework of facts for a
unified natural philosophy, Monism. The _monon_, the “one,” embracing
all things, that included nature in itself and itself in nature, became
the last scientific definition of what people called “God.”
Thus the volume, which had begun the system of nature with the monera,
closes with a chapter on the Monistic God—“the God in nature.” The
conception of God in human fashion is rejected. Man is merely a
vertebrate, a mammal, adapted in his whole structure to our little
planet. A supreme Being to whom we ascribe omnipresence could not
possibly be confined within the narrow limits of this vertebrate and
mammal organisation. When we try to do so we fall into unshapely
conceptions that are wholly unworthy of the most exalted of all words,
ideas, and beings. It is in this connection that Haeckel uses for the
first time the phrase “gaseous vertebrate,” that has so often been
quoted and attacked since. He means to say that we are driven to such
debasing and senseless definitions if we do not recognise in God the
essence of the whole system of things; if we form our idea of him
arbitrarily on any particular property of things within the system. We
must beware—as he expressly says—of such confused and unworthy
comparisons.
“Our philosophy,” Haeckel continues, “knows only one God, and this
Almighty God dominates the whole of nature without exception. We see his
activity in all phenomena without exception. The whole of the inorganic
world is subject to him just as much as the organic. If a body falls
fifteen feet in the first second in empty space, if three atoms of
oxygen unite with one atom of sulphur to form sulphuric acid, if the
angle that is formed by the contiguous surfaces of a column of
rock-crystal is always 120 degrees, these phenomena are just as truly
the direct action of God as the flowering of the plant, the movement of
the animal, or the thought of man. We all exist ‘by the grace of God,’
the stone as well as the water, the radiolarian as well as the pine, the
gorilla as well as the Emperor of China. No other conception of God
except this that sees his spirit and force in all natural phenomena is
worthy of his all-enfolding greatness; only when we trace all forces and
all movements, all the forms and properties of matter, to God, as the
sustainer of all things, do we reach the human idea and reverence for
him that really corresponds to his infinite greatness. In him we live,
and move, and have our being. Thus does natural philosophy become a
theology. The cult of nature passes into that service of God of which
Goethe says: ‘Assuredly there is no nobler reverence for God than that
springs up in our heart from conversation with nature.’ God is almighty:
he is the sole sustainer and cause of all things. In other words, God is
the universal law of causality. God is absolutely perfect; he cannot act
in any other than a perfectly good manner; he cannot therefore act
arbitrarily or freely—God is necessity. God is the sum of all force, and
therefore of all matter. Every conception of God that separates him from
matter, and opposes to him a sum of forces that are not of a divine
nature, leads to amphitheism (or ditheism) and on to polytheism. In
showing the unity of the whole of nature, Monism points out that only
one God exists, and that this God reveals himself in all the phenomena
of nature. In grounding all the phenomena of organic or inorganic nature
on the universal law of causality, and exhibiting them as the outcome of
‘efficient causes,’ Monism proves that God is the necessary cause of all
things and the law itself. In recognising none but divine forces in
nature, in proclaiming all natural laws to be divine, Monism rises to
the greatest and most lofty conception of which man, the most perfect of
all things, is capable, the conception of the unity of God and nature.”
The book closes with these words and a quotation from Goethe. It had
opened with a quotation from Goethe. Goethe runs through the whole of
the two energetic volumes like an old and venerable anthem. The stalwart
fighter not only traces his whole Monistic philosophy to Goethe: not
only owes to him the very idea of morphology. In front of the second and
more strictly Darwinistic volume he has a dedication “to the founders of
the theory of evolution,” and between Darwin and Lamarck we find the
name of Goethe. It was Haeckel’s firm conviction that Goethe not only
believed in the unity of God and nature, but literally in the natural
evolution of the various species of animals and plants from each other.
In this conviction, which claims Goethe explicitly for Darwin, he has
never been shaken, although his own friends and convinced evolutionists
(Oscar Schmidt, for instance) have often opposed him on the point.
Much has been written since the days of the _General Morphology_ both
for and against this Goethe-Darwin theory, but I cannot see that we have
got much further with it. I still find that a candid study of some of
Goethe’s smaller writings, such as the _History of my Botanical_
_Studies_, the criticism of D’Alton’s _Sloths and Pachyderms_ (which is
very important), and several others, compels us to think that Goethe
really believed, in a strikingly Darwinian way, in a slow transformation
and evolution of animal and plant species in virtue of purely natural
laws; and that he always laid great stress on this idea of his as an
original notion, far in advance of the professional science of his time.
We not only have several clear passages, but the whole point of his
argument really rests on this idea. Hence, apart altogether from the
pedantry that tries to make a cabalistic mystery out of Goethe’s works,
and always reads B for A and C for B, it does seem that there was truth
in Haeckel’s first view of the matter, in spite of all the ink that has
been shed over it and the vast amount of word-splitting exegesis.
Darwinism has, in a certain sense, its German side, even apart from all
that Haeckel has done for it.
* * * * *
This was the book, then, that the deeply afflicted author wrung from
himself as his “testament.” It was written and printed with
unprecedented speed. When the first copies were issued, the author had a
feeling that he had nearly “done for himself.” He could not sleep. The
state of his nerves gave great concern to his friends, who were watching
him most anxiously. With a stolid fatalism, as if nothing mattered now,
he yielded to their pressing advice, and decided to travel for a time.
Far away on the blue Atlantic, at the gate to all the glories of the
tropics, there is an island, Teneriffe, that was counted one of “the
isles of the blest” in the old Roman days. A huge volcano rises from it,
and on its flanks we find all the zones of the geography of plants, as
in a model collection. Humboldt has given us a splendid description of
it, as the first station of his voyage to the tropics. “The man who has
some feeling for the beauty of Nature,” he says, “will find a more
powerful restorative than climate on this lovely island. No place in the
world seems to me better calculated to banish sorrow and restore peace
to an embittered soul.” Haeckel went there.
It was not an expensive journey, but it came as a fresh greeting from
Nature. It was a new ocean after the long studies on the Mediterranean.
What might it not afford in the way of medusæ and other zoological
prizes when the general beauty of the landscape, that had enchanted
Humboldt, had been fully enjoyed. With a mingling of his overflowing
passion for Nature, and the gloomy fatalism that told him this would be
his “last voyage” after his “last book,” he asked permission to leave
Jena in the autumn of 1866, when the printing of the _Morphology_ was
completed, and set out. It was no more to be his last voyage than the
_Morphology_ to be his last testament. Although still subdued with
resignation in his inner life, he came home in the spring of 1867 with a
new elasticity of body and mind, restored by the influence of the palms
and bananas and spurge, and braced for the great struggle of his life
that was now to begin in earnest.
The voyage had really two aims. To see the volcano above a palm-clad
coast, with the Atlantic Ocean bringing its medusæ; and to work for
Darwin.
A personal connection between the two had already been formed as a
matter of course. Darwin, almost confined for years to his isolated home
at Down owing to his constant ill-health, had received a copy of the
_Radiolaria_, and the correspondence had begun. The work had as yet met
with little encouragement from the ranks of exact scientists. It cannot
have been a matter of indifference to Darwin personally that so
distinguished a work, a real model of professional research, had come
over to him. Proofs of the _Morphology_ were sent over to Down before
the book was ready for publication. Darwin read German with difficulty,
but in this case he was stimulated to make an unusual effort. At last
Haeckel himself made his appearance at the master’s home. It seemed as
though he had to visit him in person to receive his blessing. It was, at
all events, a happy moment in the history of Darwinism when the two men
first met whose names will be inseparable in literature.
This was in October, 1866; Darwin had sent his carriage to bring Haeckel
from the station. A sunny autumn morning smiled on the homely and
beautiful English landscape with its bright woods and golden broom and
red erica and evergreen oaks. Haeckel has described their first meeting.
“When the carriage drew up before Darwin’s house, with its ivy and its
shadowy elms, the great scientist stepped out of the shade of the
creeper-covered porch to meet me. He had a tall and venerable
appearance, with the broad shoulders of an Atlas that bore a world of
thought: a Jove-like forehead, as we see in Goethe, with a lofty and
broad vault, deeply furrowed by the plough of intellectual work. The
tender and friendly eyes were overshadowed by the great roof of the
prominent brows. The gentle mouth was framed in a long, silvery white
beard. The noble expression of the whole face, the easy and soft voice,
the slow and careful pronunciation, the natural and simple tenor of his
conversation, took my heart by storm in the first hour that we talked
together, just as his great work had taken my intelligence by storm at
the first reading. I seemed to have before me a venerable sage of
ancient Greece, a Socrates or an Aristotle.”
They were delighted to meet each other, for they were like natures, in
their best qualities. Darwin had more passion in him than he ever
expressed, and behind all Haeckel’s impetuosity there was the naïve and
yielding temper of the child. He poured out his anger against the
stubborn and bewigged professors who still held out against the luminous
truth of the theory of evolution. Darwin put his hand on his shoulder,
smiled, and said they were rather to be pitied than blamed, and that
they could not keep back permanently the stream of truth. At heart,
however, he was delighted with his fiery pupil. They were to fight their
battle shoulder to shoulder for seventeen years. During all those years
there was never the slightest disturbance of their friendship. Darwin
knew well what an auxiliary he had in Haeckel. It is true that he wrote
him a wonderful letter occasionally, in which he used the right of a
senior to warn Haeckel not to deal so violently with his opponents.
Violence only had the effect of making onlookers side with the party you
attacked. We must be careful not to be too hasty in setting things up as
positive truths, as we see every day people starting from the same
premises and coming to opposite conclusions. But he was generally at one
with Haeckel, and had the good spirit to acknowledge it openly. When
Haeckel’s _History of Creation_ raised up the most extreme parties, and
started the cry that a distinction must be drawn at once between
Darwin’s real scientific ideas and Haeckel’s desperate excursions into
natural philosophy, Darwin said, in the _Descent of Man_, which he had
begun much earlier, but did not publish for some time, that he would
never have written his book if he had then known Haeckel’s _History of
Creation_. Haeckel had anticipated so much that he wished to say. And
when Virchow attacked Haeckel in 1877, Darwin spoke very severely of the
opponents who would make the eternal freedom to teach the truth
dependent on the accidental conditions of a modern State. Haeckel
visited him twice at Down. On February 12, 1882, he sent Darwin his
congratulations on his seventy-third birthday from the summit of Adam’s
Peak in Ceylon. This was his last greeting. Darwin died two months
afterwards. There was a touch of romance in this last communication of
the two great warriors. On the summit of the mountain, almost as sharp
as a needle, and 2,500 yards above the Indian Ocean, a tiny temple of
Buddha hangs like a stork’s nest suspended by chains. Buddha is believed
to have left his footprints on the rocks here. The Mohammedan tradition,
however, says it was done by Adam as he stood on one foot and bemoaned
the loss of Paradise. In front of this holy trace, a depression in the
rock about a foot long, Haeckel made a speech to his travelling
companions, and they broke the neck of a bottle of Rhine wine to
Darwin’s health. It is no little stretch of humanity’s pilgrimage, from
Adam to Buddha and on to Darwin.
[Illustration:
ERNST HAECKEL AND HIS ASSISTANT MIKLUCHO-MACLAY
AT LANZAROTE, IN THE CANARIES, 1867.
]
In October, 1866, Haeckel had a companion in a teacher from Bonn,
Richard Greeff (afterwards professor of zoology at Marburg). They took
ship from London to Lisbon, where they were long detained for
quarantine, though the annoyance was somewhat relieved by the discovery
of an interesting medusa in the brackish water of the Tagus. They then
went to Madeira and Teneriffe, not right into the tropics, but where
they might get a breath of it, as it were. Two of Haeckel’s pupils, who
both became well known afterwards, Miklucho-Maclay and Fol, were with
them. Greeff has given a full account of the journey in a whole volume
(published at Bonn, 1868), and Haeckel has written of it in two
articles, one of which (in the fifth volume of the _Zeitschrift der
Gesellschaft für Erdkunde_, Berlin, 1870) is a perfect masterpiece of
narrative and description of scenery. After a long search they chose as
the best station for studying marine animals, especially the medusæ, the
little island of Lanzarote, instead of one of the chief islands. Here
they fished and drew, in the manner taught by Johannes Müller, for three
months, from December, 1866, to February, 1867. It is not exactly an
ideal place. “Imagine yourself dumped down on the moor!” Haeckel said
afterwards in his description of it. A piece of arid land that looked
like a strip of the Sahara in the middle of the ocean. There is hardly
any water, and the vegetation is correspondingly meagre. Across the
middle of the island stretches a chain of volcanic craters, and old
lava-fields run down from them as far as the coast. Everything of
zoological interest in the place was to be found in the sea. There they
found abundance. As in Messina, certain local currents drove the rich
animal plancton together until there were literally rivers or streets of
tiny animals. One had only to dip in one’s nets and glasses, and bring
up whole shoals with every drop of water.
Haeckel had come chiefly to study the medusæ. But this led him on much
further to a great zoological problem. In his _General Morphology_ he
had expounded his brilliant ideas on the subject of individuality, and
now he encountered in the flesh one of the greatest marvels of animal
individuality. He had shown how the higher individual is always made up
of a community, a kind of state, of lower individuals. In the simplest
instance there are the cells. Each of them is an individual. Millions of
these individuals, banded together with division of labour for great
collective operations, make up the human frame, and therefore the human
“individual.” In the same way others form a beetle, a snail, or a single
medusa. Sometimes, however, these higher individuals enter in turn into
social combinations to form still higher communities. Human beings form
social commonwealths, with division of labour among the individuals.
Bees and ants form their communities in the same way. But in the latter
cases the texture of the community seems to be much looser than in the
preceding one. It is not so easy for the imagination to grasp a human
commonwealth or a colony of bees as a real “over-individual.” It is,
therefore, extremely instructive to find that at least one animal
community of this kind is of so firm a texture that even on the most
superficial examination it is recognised at once as an individual. This
is found in one of the groups of the medusæ, the siphonophores, or
social medusæ.
A number of single medusæ, each of which corresponds to what we regard
as the individual man, combine and form a new body, a social individual.
As citizens of this new state they have introduced the most rigid
division of labour. One medusa does nothing but eat, and it thus
provides nourishment for the rest, as they are all joined in one body.
Another accomplishes the swimming movement; another has been converted
entirely into a reproductive organ. In a word, the whole has become a
“unity” once more, equipped with its various organs like any large body.
Sometimes thousands of separate medusæ enter into the structure of one
of these wonders of the deep. And as each of the medusæ is generally a
very pretty, flower-like creature, the social groups with their charming
colours look like floating garlands of flowers made of transparent and
tinted crystal. Their beauty would soon fix Haeckel’s attention, but
their bearing on his theory of individuality would give them an even
greater value. For several years he had searched most attentively in the
animal world for these “over-individuals” of the highest class. In the
morphology he had had to be content with an old illustration of
something of the kind, the star-fish. It was supposed to be a
combination of vermalians. In this case the hypothesis has broken down,
though there was a good deal to be said for it at first, and it was
abandoned by him afterwards. But now, when he saw enormous numbers of
siphonophores in the animal streams at Lanzarote, he entered upon a
decisive study of the meaning of these real “social animals.” A social
medusa has so great an appearance of unity that those who discovered it
first did not believe it was a community, but a very complicated
individual medusa. Vogt (1847) and Leuckart (1851) had denied this, and
declared it to be a social group. But the controversy was still going
on, as there was much difference of opinion as to the meaning of
“social” and “state.” Haeckel now succeeded at Lanzarote in tracing for
the first time the development of one of these siphonophores from the
ovum. He was able to show that from the ovum only a single simple medusa
is developed. This, then, becomes the parent of the community; it
produces the rest of the members, not by a new sexual generation, but by
budding out from itself, until the whole garland of connected
individuals is ready to constitute the new over-individual, or the
community. These luminous investigations were published three years
afterwards (1869) in a work that was crowned by the Utrecht Society of
Art and Science (_The Embryology of the Siphonophoræ_, with fourteen
plates, published at Utrecht). But Haeckel returned time after time in
later years to this group of animals with such great philosophic and
zoological interest. When he had put before him in the eighties the
whole of the siphonophores brought home by the splendid _Challenger_
expedition, he combined the material with the results of his own studies
in a fine work, which was included (in English) in the publications of
the _Challenger_ series at London, as the 28th volume of the _Zoology of
the Challenger_, 1888. The voluminous work is illustrated with fifty
masterly plates, some of them coloured, by Haeckel himself. The most
important part of the text was also published in German at Jena, with
the title, _System of the Siphonophoræ_. There is a good popular account
of the siphonophore question in his lecture on “The Division of Labour
in Nature and in Human Life” (1869). A few of these beautiful forms are
also given on coloured plates in his illustrated work, _Art-forms in
Nature_. Every thoughtful man ought, whatever his position is as regards
Haeckel’s ideas, to glance at this material that he has so vigorously
and clearly presented.
While he was conducting this research into the embryonic development of
the siphonophores, Haeckel made certain experiments on phenomena that
have lately been made the subject of a special “experimental mechanical
embryology” by some of his pupils, particularly Professor Roux, of
Halle. He cut up siphonophore ova into several pieces at the
commencement of their development, and saw an incomplete social medusa
develop from each fragment.
[Illustration:
A SIPHONOPHORE
(_Disconalia gastroblasta._)
]
Thus the journey, like the earlier one to Messina, brought the
indefatigable student into touch once more with a “philosophical
animal.” This alone would have made it well worth the trouble. How many
more of the kind the future might still have in reserve for him! In the
quiet months at Puerto del Arrecise, on Lanzarote, he was gradually
restored to his spiritual balance. Nature had taken much from him, but
she offered him an inexhaustible return. His elasticity and vigour of
frame had been restored before he left Teneriffe. In a twenty-two hours’
tour, only interrupted by two hours’ sleep, he had climbed to the
highest summit of the Peak, in such an unfavourable season (in the
November snow) that the native guides would not go any further in the
end; all those who were with him except one stopped short a little way
from the top. The short rest at the summit (4,128 yards above the
sea-level, on the icy edge of the crater) was greatly enjoyed by him. He
could see over a distance of 5,700 square miles, as much as one-fourth
of the whole of Spain. “The extraordinary range and height of the
horizon gives one a vague idea of the infinity of space. The deep
unbroken silence and the consciousness that we have left all animal and
vegetal life far behind, produce a profound feeling of solitude. One
feels oneself, with a certain pride, master of the situation that has
been secured with so much trouble and risk. But the next moment one
feels what we really are—momentary waves in the infinite ocean of life,
transitory combinations of a comparatively small number of organic
cells, which, in the last resort, owe their origin and significance to
the peculiar chemical properties of carbon. How small and mean at such
moments do we find the little play of human passions that unfolds itself
far below in the haunts of civilisation! How great and exalted in
comparison does free Nature seem, as it unrolls before us, in one vast
picture, the whole majesty and splendour of its creative power!” Thus he
himself describes the moment. Something of that feeling of exalted
solitude entered into his life. He stood firm and undazed—come what
might.
------------------------------------------------------------------------