It seems hardly credible that there should exist people who profess
to accept the Darwinian theory of development of species in all
its fulness, and yet reject the idea of the human mind having been
evolved by slow stages from the primitive sense-organ of our lowliest
ancestors, the Protista. Such inconsistency seems almost puerile, and,
were it not for the fact that the admission of this truth would be the
final blow at the various faiths of the world, we should not be called
upon to-day to defend a position so utterly impregnable as that assumed
by Haeckel and others in regard to the evolution of the human mind.
When education has advanced further there will, we must hope, be less
of this shutting of the eyes to obvious truths for the mere sake of
propping up for a little while longer the belief in a batch of fairy
tales and preposterous legends. As we look around us upon the wonderful
objects of nature we see everywhere animation and law; the heavens
above are full of life—suns, planets, moons, and other celestial
bodies incessantly moving to and fro, all bound in their courses by
the immutable laws of nature; the vast ocean, teeming with myriads
of living beings, is incessantly rolling and roaring like some great
monster, but never exceeds the limits which nature has assigned to
its action; and the whole face of the earth presents a constant scene
of activity of some kind or other—volcanoes discharging their molten
fluid, huge glaciers grinding along the ground, monster rivers rushing
forward with incessant roar, and the vegetable and animal kingdoms
increasing and multiplying at a marvellous pace. All this is life—in
fact, everything we see around us, of whatever form or shape, is life
of some sort. The very ground upon which we stand is full of life,
each particle of dust being held to its fellow particles by mutual
attraction; and there is not a single atom of the earth’s substance or
of the whole universe that we can say is minus this property of life
or activity; nothing in the universe that we know of ever remains for
one moment in a state of rest; everything is constantly moving, and
every particle of the whole contributes its own share to the general
activity which we term motion or life. The whole universe is a huge
manifestation of phenomena, which make up the sum-total of life or
activity. The sun rotating on its axis is one form of life; the moon
silently wandering round our planet is another form of life; the trees
and animals growing and multiplying on the land are other forms; and
every lump of ore taken out of the ground and every paving stone in
our streets are other forms of life. Every particle of every substance
whatever is in a state of continual motion, and therefore full of life.
In fact, it is this very motion or life that sustains matter; for
matter could not exist—that is, its particles could not hold together,
and thus form substance—without the life, motion, activity, or whatever
we like to term the property which operates upon them and produces
mutual cohesion.
Life has always, therefore, been active in matter, and always will be,
for life or motion cannot be separated from matter; and, just as matter
has passed from a condition of homogeneity to one of heterogeneity,
so has life done likewise. Life possesses infinite potentiality, and
manifests itself in an infinite variety of ways by means of different
combinations, which it brings about in the molecular atoms of universal
matter. It acts, for instance, upon a planet by causing its particles
to hold together in one mass apart from other bodies of a similar or
dissimilar character; it also acts upon what we unscientifically call
inanimate nature by causing its particles to hold together, forming in
one case a stone, in another a metal, etc.; and it acts upon what we
term animated nature by causing its molecules to combine and procreate.
This power of attraction and cohesion of particles of universal matter
is life, and it depends entirely upon what particular combination of
the molecular atoms of universal matter takes place whether a sun, a
moon, a planet, a stone, a crystal, a sponge, a tree, or a man be the
result. This much is certain, however, that not one of these bodies
can ever be produced except by an evolutionary process subject to the
universal and unchangeable law which fixes the sequence.
Animal life, as distinct from all other life, is a comparatively late
development or manifestation in the sequence of universal phenomena.
This world on which we live had existed as a compact body for millions
of ages before life assumed the character of animal life; and so
gradual was the process of evolution from the primal condition of
homogeneity, through all the manifold stages of life, until the
condition of animal life was reached, that it is impossible to fix
a particular moment when such life became manifest. So it is with
every stage of the evolutionary process; there are no starting-places
for particular species, the whole being one continuous unfolding of
phenomena, without arrest of any kind.
It is equally impossible to fix a particular point or moment for the
manifestation of the crystal life as it is for that of the animal or
the vegetable life. All are but gradual unfoldings of the universal
potentiality. Crystal life is the highest development of what is
popularly but erroneously termed inanimate nature, and differs not one
iota from Moneron life, which is the lowest form of animal life, in
its constituent elements, the only difference between the two being in
the mode of combination of the elementary particles composing each.
The crystal elements combine in such proportions as to cause the mass
to hold together like other solid bodies, its bulk being increased by
the deposition of fresh particles upon its outer surface; while the
Moneron elements combine in such a manner as to render the body soft
and yielding, so that it can absorb nutriment from without to within
and multiply by fission. The elements of both are identically the same:
the manner of combination causes the differences between them. Many
learned men declare that, if this were true, we ought to be able to
take the five elements—viz., Oxygen, Hydrogen, Nitrogen, Carbon, and
Sulphur—in the necessary proportions, and, by uniting them, form animal
life. This, they say, has been attempted, and the result has been
failure; therefore, animal life could not have been generated in that
manner, but must have been specially created at some particular moment.
This argument is absurdly unsound. These persons might just as well
say that, to substantiate the assertion that crystals are formed of a
combination of elementary molecules, we ought to be able to take the
necessary quantity of these elements, and, by uniting them together,
form a crystal; and that, if this cannot be done, then crystals also
require a special creation. The same argument for a special creation
will apply to every species of the animal, vegetable, and mineral
kingdoms. Protoplasm is the lowest form of animal life, differing from
the highest form of mineral life only in the mode of combination of
its elementary particles; but this difference causes the manifestation
of fresh phenomena, in this case as in every other modification of a
previous state of nature, which gives it the appearance of possessing
a property that had not been possessed by any substance previously,
whereas, in truth, the apparently new property is but a further
development of that previously possessed by inorganic bodies. In short,
the power of absorption possessed by the Moneron is simply one of the
many manifestations of that universal life or energy that is inherent
in all matter, and has been so from all time; but it is a comparatively
late development, occurring at a particular period in the world’s
history, when the conditions necessary for such a development were
present. Before this period no such combination of molecular atoms took
place with the same result, simply because the necessary conditions of
development were absent. In the same manner precisely there was a prior
period when no such substance as a crystal existed, the conditions
requisite for the peculiar combination of molecular atoms to result in
the formation of a crystal having been absent.
When the world had undergone sufficient evolutionary development there
came a time when such atmospheric and other conditions were present
as to permit of a modification of the then existing substances and
properties, which resulted in the formation of the crystal; and,
precisely in the same manner, and for the same reason, a further and
later modification resulted in the formation of Protoplasm, which is
the earliest form of animal life. This little substance gradually
differentiated into two distinct parts, by a nucleus being formed
in the centre of the protoplasmic mass, and became possessed with a
peculiar power of locomotion, which caused a still greater difference
to exist between itself and its ancestral stock. This power of
locomotion, again, is but a modification of that life-power of which we
have spoken, and forms a stepping-stone between the molecular action
of mineral substances and the mental wonders of the human being. The
crystal, in common with all other bodies in the mineral kingdom, always
possessed this power of locomotion to a limited extent; every one of
the individual atoms which make up the whole substance has always had
the power of locomotion, for they all attract and repel each other and
effect cohesions by their mutual attraction. This locomotive power
underwent such a modification when cell-life (Protozoa) was manifested
that not only were the constituent molecular atoms individually
possessed of this power, as before, but the whole mass of the cell
became endowed with the same property, just as a whole continent of
free people who have been in the habit of defending themselves singly
against their enemies sometimes combine and co-operate with each
other in the form of a republic, the function of the individual being
assumed by the body as a whole. The little cellular organisms, which
are called Amœbæ, possess this extended power of locomotion, and may be
seen constantly moving about in the endeavour to locate themselves in
the brightest part of their dwelling place, frequently a little pond.
They are attracted by light, which clearly proves that they possess
a degree of sensory perception, although special sense-organs are of
course wanting, the whole mass of the body being nothing more than a
single cell composed of protoplasm and nucleus. These little cellular
organisms soon unite with each other, forming small bodies composed of
several cells in a state of cohesion (Synamœbæ), and on the surface of
these multicellular organisms are shortly afterwards thrown out minute
threads or ciliae, the first attempt at separation of sense-organs
from the surface of the body. In these tiny Protozoa, those organisms
which consist of one single cell only, the Amœbæ, as well as those
consisting of several cells in a state of union, the Synamœbæ, are
able to perform all the functions of animal life—cohesion, sensation,
motion, digestion, and reproduction; but, as the organism becomes more
and more complex, these different functions are shared among several
groups of cells. This differentiation proceeds steadily stage by stage,
until at last different senses are located in different parts of the
body, and we find animals possessing eyes, ears, noses, and mouths, one
organ performing the function of sight, another that of hearing, and
so on. All these organs of sense are but parts of the general nervous
organisation of the body, which is _apparently_ absent in the Protista,
but existing potentially in the protoplasmic substance, as it also does
in every other substance in the universe.
The ciliated multiple cell-organism, in course of time, becomes
transformed into a hollow body, having a wall composed of a single
layer of cells, and this again, by invagination, or folding of itself
within itself, forms a double-walled cavity, or Gastrula, having an
external opening like a mouth. These little animals, the Gastrœada,
having an inner layer of cells (the endoderm), which carries on the
nutritive and assimilative functions of the organism, and an outer
layer (the ectoderm), which forms the general motor and sense-organ of
the body, are the first animal organisms to possess a real sense-organ
separate and distinct from other parts of the body. From this epidermal
organ of sense are developed, as higher forms of animal life make
their appearance, the nerve-cells and sense-cells which form the whole
nervous system.
In the fresh-water polyp, or Hydra, which is wanting in distinct
organs of sense and nervous system, we find a remarkable sensitiveness
to touch, warmth, and light, individual ectodermic neuro-muscular
cells performing these functions, but a far greater sensibility being
exhibited in the circle of fine prehensible tentacles surrounding the
mouth than elsewhere. Here we have a marked attempt at localisation of
sense-organs, and a manifestation of instinct, which makes the little
animal shrink from the touch.
From the Hydræ evolved the Medusæ, which, instead of being dependent
entirely on neuro-muscular cells like the parent forms, developed
minute sets of nerves and muscles, by the use of which they became
enabled to swim about easily and at their own will and pleasure. We get
in this little animal the first appearance of real nerve function, or
conductibility of stimulus along the nervous fibre to a muscle which it
causes to contract—a totally different function to the contraction of
the whole body upon a stimulus being applied to it, as in the case of
the Hydræ.
In the worm forms, which evolve from the Gastrœada, we come across
the first attempt at special sense-organ formation, in the shape of
depressions on the integument of the body. The Himatega, or sack-worms,
possess a rudimentary spinal cord, and were the parents of the first
true vertebrates, organisms without skulls or brains, but with a true
vertebral cord. These little vermiform animals, in addition to their
rudimentary spinal cords, exhibited upon the surface of the body
several small depressions, which answered the purpose of a set of
special sense-organs, one tiny depression being set apart especially
for the perception of light waves, another for the perception of sound
waves, another for the perception of odours, etc.; and thus gradually
came about that wonderful evolutionary process by which bodies became
endowed with more or less perfect special sense-organs.
As the animal kingdom developed into higher and higher forms of
life, and skulls and brains became the order of the day, the special
sense-organs became possessed of larger powers, at the same time
that the whole nervous organisation assumed higher and more complex
functions, resulting eventually in a very gradual unfolding of the most
wonderful of all the latent potentialities of universal life—the marvel
of consciousness. This is the present climax of Nature’s evolution, the
grandest and most awful achievement of that hidden and mysterious force
which baffles comprehension, and beside which all things seen, heard,
or felt pale into insignificance.
To point out the precise method of the evolution of mind, step by step,
until the final climax of consciousness was reached, would require an
abler pen than mine; therefore I shall be content to briefly notice
the different products of intellectual development in the order in
which they are unfolded, showing the analogy between ontogenesis, or
the life-history of the individual, and phylogenesis, or that of the
whole race, not now as regards bodily, but only mental, evolution. We
must ever remember that the biogenetic law insists that the process
of development in the race is reflected in miniature in the embryonic
history of every individual. In other words, it is, beyond doubt, an
accepted article of faith with biologists that the development of the
individual from the embryo _in utero_ to the full-grown man is an exact
counterpart of the development of the whole race from the primitive
protoplasmic atom, the lowly Moneron, to _homo sapiens_, equally in
regard to mental as to bodily evolution.
Every human individual commences his term of separate existence
as a tiny speck of protoplasm, and slowly advances through the
phases of separate cell-life, multicellular existence, and the
gastrula, vermiform, and pisciform stages, being finally born as a
partially-developed member of the human family, from which moment
he grows rapidly to the perfection of the adult state, having
accomplished, in the short period of about a score of years, precisely
what his counterpart, the race, effected in many millions of years.
During the period in which the individual dwells _in utero_ great
and rapid modifications take place in the general construction of
the fœtus; sensory perception makes its appearance very early, being
followed quickly by the first attempt at differentiation of special
sense-organs in the form of tiny surface depressions; the brain and
spinal system gradually take shape and make ready for future action;
and the little body slowly assumes a form suitable for separate
extra-uterine existence. At the moment of birth the brain and special
sense-organs are not yet developed to such a degree that they can
properly discharge the functions they are called upon to perform in the
mature state; they have to advance gradually to perfection in harmony
with the growth of the whole body; and thus it is that a newly-born
individual does not see, hear, or exhibit signs of consciousness until
some time has elapsed from birth, although it is, at first, quite
sensitive to cold and heat. If a lighted candle be held in front of
the eyes of a newly-born infant, and moved to and fro, it will be
at once observed that the child is totally unconscious of it; and,
if a gun be fired off in the room occupied by the child, the effect
upon the infantile organism is _nil_; but, if the air of the room be
allowed to cool, the effect will be at once perceived, for the muscles
of the child will soon begin to contract, and his vocal bellows to
act vigorously. Gradually, however, the sight, hearing, etc., become
adjusted, and the infant begins to take notice of surrounding objects,
until at about a month after birth pain and pleasure, the first
indications of the dawn of the mental powers, manifest themselves.
Conscious, as distinguished from instinctive or non-conscious, memory
appears to be exercised at about the thirteenth week, and to be
immediately followed by association of ideas, the recognition of places
and persons, and dreaming. At the same time that these indications of
intellectual development are manifesting themselves, a corresponding
unfolding of the emotions is observed. Side by side with memory appears
fear, followed by pugnacity, play, and, later, anger; while, still
later, about on a par with the first period of dreaming, or at about
the age of five months, are manifested emulation, jealousy, joy, and
grief. In about another month we notice that the child begins to
understand words, while, on the emotional side, he evinces signs of
awakening sympathy, curiosity, revenge, and gratitude, followed within
a couple of months by pride, shame, deceitfulness, passionateness,
cruelty, and ludicrousness, which show themselves at the moment the
child appears to first exercise what we term true reason. From this
point we see rapidly unfolded the higher products of intellectual
development, the first of which is morality of a very indefinite kind,
which immediately precedes articulation at the age of about fourteen
months, being closely followed by knowledge of the use of various
simple instruments, afterwards at the age of twenty months by concerted
action, and still later by speech, which generally is effected at the
age of two years, or rather earlier. Following quickly upon speech we
observe judgment, recollection, and self-consciousness manifesting
themselves, and, by the time the child has attained the age of two
years and a half, morality of a definite kind makes its appearance.
Tracing the child’s development still further, we find the next
important intellectual manifestation—viz., superstition—to take place
at about three years of age, while concurrently the following emotional
products appear—avarice, envy, hate, hope, vanity, mirth, and a love of
the beautiful, which are followed, in the course of a few months, by
awe and an appreciation of art. From this age to the condition of adult
life, the intellectual faculties develop according to the surroundings
of the individual, while, on the emotional side, reverence, remorse,
and courtesy make their appearance at about the age of five years, and
melancholy and ecstasy at about the tenth year.
In the foregoing ontogenetic mirror will be found the key to the
unfolding of the great mystery of the evolution of mind in the animal
kingdom. We have only to take the geological periods one after the
other, and study the various life-forms found in each to see at once
that, with the race, the order of sequence in the appearance of the
intellectual and emotional faculties is precisely the same as with the
individual. We may place the new-born infant intellectually on a par
with the lowly molluscs or the vermiform little animals which existed
in the Cambrian period, in which little organisms probably pain first
made its entry upon the earth, followed by the appearance of pleasure,
memory (conscious), and association of ideas in the lowly crustaceans
of the later Cambrian and early Silurian periods. With the spiders,
fishes, and crabs of the later Silurian and Devonian periods we have
brought before us the faculty of recognising places of which these
animals are capable, which places them intellectually on a level with a
child of four or five months old.
The recognition of individuals next made its appearance in the reptiles
of the Carboniferous and Permian epochs; while the birds of the Oölitic
and Cretaceous periods were the first to dream, and are thus placed on
an intellectual level with a child of five or six months. The emotional
development coincides with the intellectual, just as in the case of the
infant, for we find fear manifesting itself among the lower molluscs,
pugnacity among the crustaceans, play among spiders and crabs, anger
among reptiles, and emulation, jealousy, joy, and grief among birds. We
now rise in the palæontological scale to the Tertiary period, and find
in the Eocene age equine and other mammal forms, such as cats and pigs,
which are capable of understanding words and signs, and among which we
notice a manifestation of sympathy, curiosity, revenge, and gratitude.
In the early Meiocene age we have monkeys, dogs, and elephants
exhibiting the clearest signs of true reason, as may be observed at
the present day, and at the same time manifesting such emotional
signs as pride, shame, deceitfulness, passionateness, cruelty, and
ludicrousness, which places them on an intellectual par with the infant
of less than a year old.
In the later Meiocene age we have anthropoid apes, which may be placed
on a level with one-year-old infants, and from which evolved apes
of a higher order, which acquired the faculty of articulation, and,
afterwards becoming more human, the knowledge of the use of simple
instruments, thus reaching the intellectual level of the child of
fifteen months old. As the apes became more and more human in the
later Meiocene and early Pleistocene ages, they gradually acquired
the faculty of acting in concert and of speech; and when, having
arrived at that stage of development in which they partook more of
the character of savage man than human ape, judgment, recollection,
self-consciousness, and, lastly, definite morality manifested
themselves, thus raising the ape-like man to the level of the child of
two and a half years. In the lowest savages of to-day, as well as in
the old descendants of the ape-like men, superstition developed to a
large extent at the same time that the emotional unfolding proceeded
in the direction of avarice, envy, hate, hope, vanity, mirth, a love
of the beautiful, and afterwards art appreciation, awe, reverence,
remorse, courtesy, melancholy, and ecstasy, precisely as with the
child of from five to ten years of age. As the race improved,
becoming in turn semi-savage, semi-civilised, civilised, and cultured,
the intellectual powers, of course, developed similarly, until, at
the present day, we find men possessed of the most wonderful mental
grandeur, we might almost say, conceivable. But this would be saying
too much, for we must not forget that, just as evolution has continued
in the past from eternity, so will it continue in the future to
eternity; and who can tell to what heights the human mind may soar in
the future?
Lofty as is the human intellect at the present time, as compared with
the mental powers of those we have left far behind in the march of
evolution, it is yet very far from being able to grasp many of the
great problems of the universe, such as that of existence. Perhaps at
some future time, in millions of ages to come, these great questions
may be answered; but at present we know they baffle the wisest men,
and continually remind us of the finite and limited character of our
intellectual faculties.
This comparison of the mental development of the individual with that
of the whole race is extremely interesting, and provides ample material
for thought. By such comparison, and by it alone, can the science of
psychology ever be based on a sure and enduring foundation. It is all
very well for theologians and other biased people to declare that
animal intelligence has nothing in common with the reasoning powers
of man; but let them honestly look at the facts as they are, thanks
to the indefatigable energy and indomitable perseverance of lovers
of science and truth, now presented to us. Candid observers cannot
fail to notice that the difference between the intelligence of man
and that of the lower animals is one only of degree, and not of kind.
When we see the order of sequence being followed in the development
of the individual so like that of the whole race, not only as regards
the bodily structure, but also as regards the mental functions, can
we help arriving at the conclusion that the one is but the epitome
of the other, and that the superior intellect of man is but a higher
development of the so-called instincts of the lower animals? Have we
not at the present day, among members of the human family itself,
various degrees of intelligence, from the almost barren brains of the
lowest races of savages to the brilliant mental achievements of a
Newton or a Spencer?
It is beyond doubt that the intellectual superiority of civilised man
over his savage brethren is due to the greater multiplicity of his
objects of thought, and it follows that savage man’s intellectual
superiority over the lower animals is due to the same cause. The
actions of both have the same aim—viz., the supplying of the wants
of the physical nature and the gratifying of the desires aroused in
the mind. It is frequently asserted that man differs from the lower
animals in possessing the power of reflection; but this I hold to
be an exploded argument, and at variance with all recent teaching.
Dogs, elephants, and monkeys most certainly possess the faculty of
reflection, and it is not difficult to find races belonging to the
human family whose powers of reflection transcend hardly in the least
degree those possessed by the higher apes; while the difference
between the reflective capacity of the lowest savage, which is of the
simplest conceivable kind, and that of the civilised European, which
has developed into genius, is enormous. Then, again, it is often
said that only man is emotional; but one need only have an ordinary
acquaintanceship with domestic animals to at once see the absurdity of
this argument, for dogs are frequently observed to laugh, to cry, to
express joy and gratitude by their actions, and to betray feelings of
shame and remorse; while horses and elephants have been observed to
punish their cruel keepers in the most cunning manner and then to laugh
at the poor fellows’ discomfiture. As to the “conscience argument,”
so frequently brought forward, by religionists especially, all I have
to say here is that conscience, or the knowledge of the distinction
between right and wrong, is not an inherent quality of the human mind,
being merely a result of the operation of the reflective faculty aided
by experience, as is quite evident from the fact that the ideas of
morality vary according to the age in which we live. The same may be
said about the greatest of all the arguments against evolution—viz.,
that of language; for, just as conscience is but a product of
reflection and experience, so is language also. It is a mistake to
imagine that the power of speech is possessed by man alone, and that
his language differs altogether from the cries and signals of the lower
animals, for such is not the case. Many animals possess the faculty of
speech, and human language differs from that of the lower animals only
in its degree of development, and in no sense in its origin. Probably
all language originated in interjection, or the “instinctive expression
of the subjective impressions derived from external nature,” as Mr.
Farrar puts it. And, just as the reflective powers of the race were
developed and shone more brilliantly as each stage in the evolutionary
march of intellect was passed, so did language pass from the simple
monosyllabic cries to the complex dialects of modern civilisation; and
it is worthy of notice that, at the present day, or at any rate very
recently, there were races of savage men inhabiting this earth who
possessed no language at all, and could not, on account of their mode
of living, be placed on a higher intellectual level than the higher
apes; while we have the authority of the leading philologists of the
times in support of the fact that the monosyllabic cries of some of the
lower human tribes are quite within the grasp of the ape’s voice.
Human beings have been discovered in wild and hitherto unexplored
regions who have not the remotest idea of what we should term
civilisation. They lead a wandering and useless life, sleeping at
nights, not in huts, nor in caves, but squatting among the branches of
tall trees, where they are placed out of the reach of savage animals.
They do not appear capable of expressing their thoughts in sentences,
but make use of exclamatory grunts, which serve the purposes of speech
quite sufficiently for their limited requirements; and their general
appearance approaches to a remarkable extent that of the higher apes,
in that they are almost completely covered with hair, possess a dirty
brown skin, short legs, long arms, and full abdomens, can pick up
stones, sticks, etc., with their toes as well as their fingers, and
show few if any signs of intellectual powers. Let any one visit the
Zoological Gardens, in London, and carefully observe the apes exhibited
there, and then say whether there is a vast difference between some
of them and the human beings who answer to the above description. One
need but visit the travelling menagerie of Messrs. Edmunds, and view
their “missing link,” an excellent sample of the chimpanzee troglodyte,
to see that the difference between man and the lower animals is one
only of degree, quite as much as regards intellect as bodily form. I
once saw exhibited in the _Jardin d’Acclimatation_, in Paris, a lot of
Patagonian or Fuegan (I forget which) natives, who were very little
superior intellectually to the chimpanzee. They were stark naked, in a
wretchedly dirty condition, and appeared quite incapable of anything
like sustained mental effort. But these are by no means the lowest
among the human species.
In conclusion, I need only re-state my opinion that all so-called
living things are but products of the development of protoplasm,
whether belonging to the animal or vegetable kingdoms; that this
protoplasm possesses the property of vitality, or the power of
perceiving stimuli of various kinds and responding to them by definite
movements; that the phenomena of mind are but functional manifestations
of this protoplasmic development; and that the highest intellectual
product of the human mind exists and has existed from eternity in a
state of latent potentiality in every atom of protoplasm, as well as in
every particle of matter in the universe.