made a biologist, but who still keep alive your sympathy with that
class of enquiries which nature intended you to pursue and adorn--will
excuse me to your brethren if I say that some of them seem to form an
inadequate estimate of the distance which separates the microscopic
from the molecular limit, and that, as a consequence, they sometimes
employ a phraseology which is calculated to mislead. When, for example,
the contents of a cell are described as perfectly homogeneous, as
absolutely structureless, because the microscope fails to distinguish
any structure, then I think the microscope begins to play a mischievous
part. A little consideration will make it plain to all of you that the
microscope can have no voice in the real question of germ structure.
Distilled water is more perfectly homogeneous than the contents of any
possible organic germ. What causes the liquid to cease contracting at
39° Fahr., and to grow bigger until it freezes? It is a structural
process of which the microscope can take no note, nor is it likely to
do so by any conceivable extension of its powers. Place this distilled
water in the field of an electro-magnet, and bring a microscope to
bear upon it. Will any change be observed when the magnet is excited?
Absolutely none; and still profound and complex changes have occurred.
First of all, the particles of water are rendered diamagnetically
polar; and secondly, in virtue of the structure impressed upon it
by the magnetic strain of its molecules, the liquid twists a ray of
light in a fashion perfectly determinate both as to quantity and
direction. It would be immensely interesting to both you and me if one
whom I hoped to see here present,[5] who has brought his brilliant
imagination to bear upon this subject, could make us see as he sees the
entangled molecular processes involved in the rotation of the plane
of polarisation by magnetic force. While dealing with this question,
he lived in a world of matter and of motion to which the microscope
has no passport, and in which it can offer no aid. The cases in which
similar conditions hold are simply numberless. Have the diamond, the
amethyst, and the countless other crystals formed in the laboratories
of nature and of man no structure? Assuredly they have; but what can
the microscope make of it? Nothing. It cannot be too distinctly borne
in mind that between the microscope limit and the true molecular limit
there is room for infinite permutations and combinations. It is in
this region that the poles of the atoms are arranged, that tendency
is given to their powers, so that when these poles and powers have
free action and proper stimulus in a suitable environment, they
determine first the germ and afterwards the complete organism. This
first marshalling of the atoms on which all subsequent action depends
baffles a keener power than that of the microscope. Through pure
excess of complexity, and long before observation can have any voice
in the matter, the most highly trained intellect, the most refined and
disciplined imagination, retires in bewilderment from the contemplation
of the problem. We are struck dumb by an astonishment which no
microscope can relieve, doubting not only the power of our instrument,
but even whether we ourselves possess the intellectual elements which
will ever enable us to grapple with the ultimate structural energies of
nature.
But the speculative faculty, of which imagination forms so large a
part, will nevertheless wander into regions where the hope of certainty
would seem to be entirely shut out. We think that though the detailed
analysis may be, and may ever remain, beyond us, general notions may
be attainable. At all events, it is plain that beyond the present
outposts of microscopic enquiry lies an immense field for the exercise
of the speculative power. It is only, however, the privileged spirits
who know how to use their liberty without abusing it, who are able to
surround imagination by the firm frontiers of reason, that are likely
to work with any profit here. But freedom to them is of such paramount
importance that, for the sake of securing it, a good deal of wildness
on the part of weaker brethren may be overlooked. In more senses
than one Mr. Darwin has drawn heavily upon the scientific tolerance
of his age. He has drawn heavily upon _time_ in his development
of species, and he has drawn adventurously upon _matter_ in
his theory of pangenesis. According to this theory, a germ already
microscopic is a world of minor germs. Not only is the organism as a
whole wrapped up in the germ, but every organ of the organism has there
its special seed. This, I say, is an adventurous draft on the power of
matter to divide itself and distribute its forces. But, unless we are
perfectly sure that he is overstepping the bounds of reason, that he
is unwittingly sinning against observed fact or demonstrated law--for
a mind like that of Darwin can never sin wittingly against either fact
or law--we ought, I think, to be cautious in limiting his intellectual
horizon. If there be the least doubt in the matter, it ought to be
given in favour of the freedom of such a mind. To it a vast possibility
is in itself a dynamic power, though the possibility may never be drawn
upon. It gives me pleasure to think that the facts and reasonings of
this discourse tend rather towards the justification of Mr. Darwin than
towards his condemnation, that they tend rather to augment than to
diminish the cubic space demanded by this soaring speculator; for they
seem to show the perfect competence of matter and force, as regards
divisibility and distribution, to bear the heaviest strain that he has
hitherto imposed upon them.
In the case of Mr. Darwin, observation, imagination, and reason
combined have run back with wonderful sagacity and success over a
certain length of the line of biological succession. Guided by analogy,
in his ‘Origin of Species,’ he placed at the root of life a primordial
germ, from which he conceived the amazing richness and variety of
the life that now is upon the earth’s surface might be deduced. If
this were true, it would not be final. The human imagination would
infallibly look behind the germ, and enquire into the history of its
genesis. Certainty is here hopeless, but the materials for an opinion
may be attainable. In this dim twilight of conjecture the enquirer
welcomes every gleam, and seeks to augment his light by indirect
incidences. He studies the methods of nature in the ages and the
worlds within his reach, in order to shape the course of speculation
in the antecedent ages and worlds. And though the certainty possessed
by experimental enquiry is here shut out, the imagination is not left
entirely without guidance. From the examination of the solar system,
Kant and Laplace came to the conclusion that its various bodies once
formed parts of the same undislocated mass; that matter in a nebulous
form preceded matter in a dense form; that as the ages rolled away,
heat was wasted, condensation followed, planets were detached,
and that finally the chief portion of the fiery cloud reached, by
self-compression, the magnitude and density of our sun. The earth
itself offers evidence of a fiery origin; and in our day the hypothesis
of Kant and Laplace receives the independent countenance of spectrum
analysis, which proves the same substances to be common to the earth
and sun. Accepting some such view of the construction of our system as
probable, a desire immediately arises to connect the present life of
our planet with the past. We wish to know something of our remotest
ancestry. On its first detachment from the central mass, life, as
we understand it, could hardly have been present on the earth. How
then did it come there? The thing to be encouraged here is a reverent
freedom--a freedom preceded by the hard discipline which checks
licentiousness in speculation--while the thing to be repressed, both in
science and out of it, is dogmatism. And here I am in the hands of the
meeting--willing to end, but ready to go on. I have no right to intrude
upon you, unasked, the unformed notions which are floating like clouds,
or gathering to more solid consistency in the modern speculative
scientific mind. But if you wish me to speak plainly, honestly, and
undisputatiously, I am willing to do so. On the present occasion--
You are ordained to call, and I to come.
Two views, then, offer themselves to us. Life was present potentially
in matter when in the nebulous form, and was unfolded from it by the
way of natural development, or it is a principle inserted into matter
at a later date. With regard to the question of time, the views of
men have changed remarkably in our day and generation; and I must
say as regards courage also, and a manful willingness to engage in
open contest, with fair weapons, a great change has also occurred.
The clergy of England--at all events the clergy of London--have nerve
enough to listen to the strongest views which any one amongst us would
care to utter; and they invite, if they do not challenge, men of the
most decided opinions to state and stand by those opinions in open
court. No theory upsets them. Let the most destructive hypothesis be
stated only in the language current among gentlemen, and they look it
in the face. They forego alike the thunders of heaven and the terrors
of the other place, smiting the theory, if they do not like it, with
honest secular strength. In fact, the greatest cowards of the present
day are not to be found among the clergy, but within the pale of
science itself.
Two or three years ago in an ancient London College--a clerical
institution--I heard a very remarkable lecture by a very remarkable
man. Three or four hundred clergymen were present at the lecture. The
orator began with the civilisation of Egypt in the time of Joseph;
pointing out that the very perfect organisation of the kingdom, and the
possession of chariots, in one of which Joseph rode, indicated a long
antecedent period of civilisation. He then passed on to the mud of the
Nile, its rate of augmentation, its present thickness, and the remains
of human handywork found therein; thence to the rocks which bound the
Nile valley, and which teem with organic remains. Thus in his own clear
and admirable way he caused the idea of the world’s age to expand
itself indefinitely before the mind of his audience, and he contrasted
this with the age usually assigned to the world. During his discourse
he seemed to be swimming against a stream; he manifestly thought that
he was opposing a general conviction. He expected resistance; so did
I. But it was all a mistake: there was no adverse current, no opposing
conviction, no resistance, merely here and there a half-humorous, but
unsuccessful attempt to entangle him in his talk. The meeting agreed
with all that had been said regarding the antiquity of the earth
and of its life. They had, indeed, known it all long ago, and they
good-humouredly rallied the lecturer for coming amongst them with so
stale a story. It was quite plain that this large body of clergymen,
who were, I should say, the finest samples of their class, had entirely
given up the ancient landmarks, and transported the conception of
life’s origin to an indefinitely distant past.
This leads us to the gist of our present enquiry, which is this:--Does
life belong to what we call matter, or is it an independent principle
inserted into matter at some suitable epoch--say when the physical
conditions became such as to permit of the development of life? Let us
put the question with all the reverence due to a faith and culture in
which we all were cradled--a faith and culture, moreover, which are the
undeniable historic antecedents of our present enlightenment. I say,
let us put the question reverently, but let us also put it clearly and
definitely. There are the strongest grounds for believing that during
a certain period of its history the earth was not, nor was it fit to
be, the theatre of life. Whether this was ever a nebulous period, or
merely a molten period, does not much matter; and if we revert to
the nebulous condition, it is because the probabilities are really
on its side. Our question is this:--Did creative energy pause until
the nebulous matter had condensed, until the earth had been detached,
until the solar fire had so far withdrawn from the earth’s vicinity
as to permit a crust to gather round the planet? Did it wait until
the air was isolated, until the seas were formed, until evaporation,
condensation, and the descent of rain had begun, until the eroding
forces of the atmosphere had weathered and decomposed the molten rocks
so as to form soils, until the sun’s rays had become so tempered by
distance and by waste as to be chemically fit for the decompositions
necessary to vegetable life? Having waited through those Æons until the
proper conditions had set in, did it send the fiat forth, ‘Let Life
be!’? These questions define a hypothesis not without its difficulties,
but the dignity of which was demonstrated by the nobleness of the men
whom it sustained.
Modern scientific thought is called upon to decide between this
hypothesis and another: and public thought generally will afterwards be
called upon to do the same. You may, however, rest secure in the belief
that the hypothesis just sketched can never be stormed, and that it is
sure, if it yield at all, to yield to a prolonged siege. To gain new
territory modern argument requires more time than modern arms, though
both of them move with greater rapidity than of yore. But however
the convictions of individuals here and there may be influenced, the
process must be slow and secular which commends the rival hypothesis
of Natural Evolution to the public mind. For what are the core and
essence of this hypothesis? Strip it naked and you stand face to face
with the notion that not alone the more ignoble forms of animalcular
or animal life, not alone the nobler forms of the horse and lion, not
alone the exquisite and wonderful mechanism of the human body, but
that the human mind itself--emotion, intellect, will, and all their
phenomena--were once latent in a fiery cloud. Surely the mere statement
of such a notion is more than a refutation. But the hypothesis would
probably go even further than this. Many who hold it would probably
assent to the position that at the present moment all our philosophy,
all our poetry, all our science, and all our art--Plato, Shakspeare,
Newton, and Raphael--are potential in the fires of the sun. We long to
learn something of our origin. If the Evolution hypothesis be correct,
even this unsatisfied yearning must have come to us across the ages
which separate the unconscious primeval mist from the consciousness
of to-day. I do not think that any holder of the Evolution hypothesis
would say that I overstate it or overstrain it in any way. I merely
strip it of all vagueness, and bring before you unclothed and
unvarnished the notions by which it must stand or fall.
Surely these notions represent an absurdity too monstrous to be
entertained by any sane mind. Let us, however, give them fair play. Let
us steady ourselves in front of the hypothesis, and, dismissing all
terror and excitement from our minds, let us look firmly into it with
the hard sharp eye of intellect alone. Why are these notions absurd,
and why should sanity reject them? The law of Relativity, of which we
have previously spoken, may find its application here. These Evolution
notions are absurd, monstrous, and fit only for the intellectual
gibbet in relation to the ideas concerning matter which were drilled
into us when young. Spirit and matter have ever been presented to us
in the rudest contrast, the one as all-noble, the other as all-vile.
But is this correct? Does it represent what our mightiest spiritual
teacher would call the Eternal Fact of the Universe? Upon the answer to
this question all depends. Supposing, instead of having the foregoing
antithesis of spirit and matter presented to our youthful minds, we had
been taught to regard them as equally worthy and equally wonderful; to
consider them in fact as two opposite faces of the self-same mystery.
Supposing that in youth we had been impregnated with the notion of
the poet Goethe, instead of the notion of the poet Young, looking
at matter, not as brute matter, but as ‘the living garment of God;’
do you not think that under these altered circumstances the law of
Relativity might have had an outcome different from its present one?
Is it not probable that our repugnance to the idea of primeval union
between spirit and matter might be considerably abated? Without this
total revolution of the notions now prevalent, the Evolution hypothesis
must stand condemned; but in many profoundly thoughtful minds such
a revolution has already taken place. They degrade neither member
of the mysterious duality referred to; but they exalt one of them
from its abasement, and repeal the divorce hitherto existing between
both. In substance, if not in words, their position as regards the
relation of spirit and matter is: ‘What God hath joined together let
not man put asunder.’ And with regard to the ages of forgetfulness
which lie between the unconscious life of the nebula and the conscious
life of the earth, it is, they would urge, but an extension of that
forgetfulness which preceded the birth of us all.
I have thus led you to the outer rim of speculative science, for
beyond the nebulæ scientific thought has never ventured hitherto, and
have tried to state that which I considered ought, in fairness, to be
outspoken. I do not think this Evolution hypothesis is to be flouted
away contemptuously; I do not think it is to be denounced as wicked.
It is to be brought before the bar of disciplined reason, and there
justified or condemned. Let us hearken to those who wisely support
it, and to those who wisely oppose it; and let us tolerate those, and
they are many, who foolishly try to do either of these things.[6] The
only thing out of place in the discussion is dogmatism on either side.
Fear not the Evolution hypothesis. Steady yourselves in its presence
upon that faith in the ultimate triumph of truth which was expressed
by old Gamaliel when he said:--‘If it be of God, ye cannot overthrow
it; if it be of man, it will come to nought.’ Under the fierce light
of scientific enquiry, this hypothesis is sure to be dissipated if it
possess not a core of truth. Trust me, its existence as a hypothesis
in the mind is quite compatible with the simultaneous existence of all
those virtues to which the term Christian has been applied. It does
not solve--it does not profess to solve--the ultimate mystery of this
universe. It leaves in fact that mystery untouched. For granting the
nebula and its potential life, the question, whence came they? would
still remain to baffle and bewilder us. At bottom, the hypothesis does
nothing more than ‘transport the conception of life’s origin to an
indefinitely distant past.’
Those who hold the doctrine of Evolution are by no means ignorant of
the uncertainty of their data, and they yield no more to it than a
provisional assent. They regard the nebular hypothesis as probable,
and in the utter absence of any evidence to prove the act illegal,
they extend the method of nature from the present into the past. Here
the observed uniformity of nature is their only guide. Within the long
range of physical enquiry, they have never discerned in nature the
insertion of caprice. Throughout this range the laws of physical and
intellectual continuity have run side by side. Having thus determined
the elements of their curve in a world of observation and experiment,
they prolong that curve into an antecedent world, and accept as
probable the unbroken sequence of development from the nebula to the
present time. You never hear the really philosophical defenders of the
doctrine of Uniformity speaking of _impossibilities_ in nature.
They never say, what they are constantly charged with saying, that
it is impossible for the Builder of the universe to alter His work.
Their business is not with the possible, but the actual--not with a
world which _might_ be, but with a world that _is_. This
they explore with a courage not unmixed with reverence, and according
to methods which, like the quality of a tree, are tested by their
fruits. They have but one desire--to know the truth. They have but one
fear--to believe a lie. And if they know the strength of science, and
rely upon it with unswerving trust, they also know the limits beyond
which science ceases to be strong. They best know that questions
offer themselves to thought which science, as now prosecuted, has not
even the tendency to solve. They keep such questions open, and will
not tolerate any unlawful limitation of the horizon of their souls.
They have as little fellowship with the atheist who says there is no
God, as with the theist who professes to know the mind of God. ‘Two
things,’ said Immanuel Kant, ‘fill me with awe: the starry heavens
and the sense of moral responsibility in man.’ And in his hours of
health and strength and sanity, when the stroke of action has ceased
and the pause of reflection has set in, the scientific investigator
finds himself overshadowed by the same awe. Breaking contact with the
hampering details of earth, it associates him with a power which gives
fulness and tone to his existence, but which he can neither analyse nor
comprehend.
SCIENTIFIC LIMIT OF THE IMAGINATION.[7]
THE CELEBRATED FICHTE, in his lectures on the ‘Vocation of the
Scholar,’ insisted on a culture for the scholar which should not
be one-sided, but all-sided. His intellectual nature was to expand
spherically and not in a single direction. In one direction, however,
Fichte required that the scholar should apply himself directly to
nature, become a creator of knowledge, and thus repay by original
labours of his own the immense debt he owed to the labours of others.
It was these which enabled him to supplement the knowledge derived
from his own researches, so as to render his culture rounded and not
one-sided.
As regards science Fichte’s idea is to some extent illustrated by
the constitution and the labours of the British Association. We have
here a body of men engaged in the pursuit of Natural Knowledge, but
variously engaged. While sympathizing with each of its departments,
and supplementing his culture by knowledge drawn from all of them,
each student amongst us selects one subject for the exercise of his
own original faculty--one line along which he may carry the light of
his private intelligence a little way into the darkness by which all
knowledge is surrounded. Thus, the geologist deals with the rocks; the
biologist with the conditions and phenomena of life; the astronomer
with stellar masses and motions; the mathematician with the relations
of space and number; the chemist pursues his atoms, while the physical
investigator has his own large field in optical, thermal, electrical,
acoustical, and other phenomena. The British Association then, as
a whole, faces physical nature on all sides and pushes knowledge
centrifugally outwards, the sum of its labours constituting what Fichte
might call the _sphere_ of natural knowledge. In the meetings of
the Association it is found necessary to resolve this sphere into its
component parts, which take concrete form under the respective letters
of our Sections.
This is the Mathematical and Physical Section. Mathematics and physics
have been long accustomed to coalesce. For, no matter how subtle a
natural phenomenon may be, whether we observe it in the region of
sense, or follow it into that of imagination, it is in the long run
reducible to mechanical laws. But the mechanical data once guessed or
given, mathematics become all powerful as an instrument of deduction.
The command of geometry over the relations of space, the far-reaching
power which organised symbolic reasoning confers, are potent both
as means of physical discovery, and of reaping the entire fruits of
discovery. Indeed, without mathematics, expressed or implied, our
knowledge of physical science would be friable in the extreme.
Side by side with the mathematical method we have the method of
experiment. Here, from a starting-point furnished by his own researches
or those of others, the investigator proceeds by combining intuition
and verification. He ponders the knowledge he possesses and tries to
push it further, he guesses and checks his guess, he conjectures and
confirms or explodes his conjecture. These guesses and conjectures
are by no means leaps in the dark; for knowledge once gained casts a
faint light beyond its own immediate boundaries. There is no discovery
so limited as not to illuminate something beyond itself. The force of
intellectual penetration into this penumbral region which surrounds
actual knowledge is not, as some seem to think, dependent upon method,
but upon the genius of the investigator. There is, however, no genius
so gifted as not to need control and verification. The profoundest
minds know best that Nature’s ways are not at all times their ways, and
that the brightest flashes in the world of thought are incomplete until
they have been proved to have their counterparts in the world of fact.
Thus the vocation of the true experimentalist may be defined as the
continued exercise of spiritual insight, and its incessant correction
and realization. His experiments constitute a body, of which his
purified intuitions are, as it were, the soul.
Partly through mathematical and partly through experimental research,
physical science has of late years assumed a momentous position in the
world. Both in a material and in an intellectual point of view it has
produced, and it is destined to produce, immense changes,--vast social
ameliorations, and vast alterations in the popular conception of the
origin, rule, and governance of natural things. By science, in the
physical world, miracles are wrought, while philosophy is forsaking
its ancient metaphysical channels and pursuing others which have been
opened or indicated by scientific research. This must become more and
more the case as philosophic writers become more deeply imbued with the
methods of science, better acquainted with the facts which scientific
men have won, and with the great theories which they have elaborated.