Chapter XVIII: Lamarck's Theory as to the Evolution of Man

Lamarck's views on the origin of man are contained in his _Recherches sur l'Organisation des Corps vivans_ (1802) and his _Philosophie zoologique_, published in 1809. We give the following literal translation in full of the views he presented in 1802, and which were probably first advanced in lectures to his classes.

"As to man, his origin, his peculiar nature, I have already stated
in this book that I have not kept these subjects in view in making
these observations. His extreme superiority over the other living
creatures indicates that he is a privileged being who has in common
with the animals only that which concerns animal life.

"In truth, we observe a sort of gradation in the intelligence of
animals, like what exists in the gradual improvement of their
organization, and we remark that they have ideas, memory; that they
think, choose, love, hate, that they are susceptible of jealousy,
and that by different inflexions of their voice and by signs they
communicate with and understand each other. It is not less evident
that man alone is endowed with reason, and that on this account he
is clearly distinguished from all the other productions of nature.

"However, were it not for the picture that so many celebrated men
have drawn of the weakness and lack of human reason; were it not
that, independently of all the freaks into which the passions of man
almost constantly allure him, the _ignorance_ which makes him the
opinionated slave of custom and the continual dupe of those who wish
to deceive him; were it not that his reason has led him into the
most revolting errors, since we actually see him so debase himself
as to worship animals, even the meanest, of addressing to them his
prayers, and of imploring their aid; were it not, I say, for these
considerations, should we feel authorized to raise any doubts as to
the excellence of this special light which is the attribute of man?

"An observation which has for a long time struck me is that, having
remarked that the habitual use and exercise of an organ
proportionally develops its size and functions, as the lack of
employment weakens in the same proportion its power, and even more
or less completely atrophies it, I am apprised that of all the
organs of man's body which is the most strongly submitted to this
influence, that is to say, in which the effects of exercise and of
habitual use are the most considerable, is it not the organ of
thought--in a word, is it not the brain of man?

"Compare the extraordinary difference existing in the degree of
intelligence of a man who rarely exercises his powers of thought,
who has always been accustomed to see but a small number of things,
only those related to his ordinary wants and to his limited desires;
who at no time thinks about these same objects, because he is
obliged to occupy himself incessantly with providing for these same
wants; finally, who has few ideas, because his attention,
continually fixed on the same things, makes him notice nothing, that
he makes no comparisons, that he is in the very heart of nature
without knowing it, that he looks upon it almost in the same way as
do the beasts, and that all that surrounds him is nothing to him:
compare, I say, the intelligence of this individual with that of the
man who, prepared at the outset by education, has contracted the
useful practice of exercising the organ of his thought in devoting
himself to the study of the principal branches of knowledge; who
observes and compares everything he sees and which affects him; who
forgets himself in examining everything he can see, who insensibly
accustoms himself to judge of everything for himself, instead of
giving a blind assent to the authority of others; finally, who,
stimulated by reverses and especially by injustice, quietly rises by
reflection to the causes which have produced all that we observe
both in nature and in human society; then you will appreciate how
enormous is the difference between the intelligence of the two men
in question.

"If Newton, Bacon, Montesquieu, Voltaire, and so many other men have
done honor to the human species by the extent of their intelligence
and their genius, how nearly does the mass of brutish, ignorant men
approach the animal, becoming a prey to the most absurd prejudices
and constantly enslaved by their habits, this mass forming the
majority of all nations?

"Search deeply the facts in the comparison I have just made, you
will see how in one part the organ which serves for acts of thought
is perfected and acquires greater size and power, owing to sustained
and varied exercise, especially if this exercise offers no more
interruptions than are necessary to prevent the exhaustion of its
powers; and, on the other hand, you will perceive how the
circumstances which prevent an individual from exercising this
organ, or from exercising it habitually only while considering a
small number of objects which are always of the same nature, impede
the development of his intellectual faculties.

"After what I have just stated as to the results in man of a slight
exercise of the organ by which he thinks, we shall no longer be
astonished to see that in the nations which have come to be the most
distinguished, because there is among them a small number of men who
have been able, by observation and reflection, to create or advance
the higher sciences, the multitude in these same nations have not
been for all that exempted from the most absurd errors, and have not
the less always been the dupe of impostors and victims of their
prejudices.

"Such is, in fact, the fatality attached to the destiny of man that,
with the exception of a small number of individuals who live under
favorable though special circumstances, the multitude, forced to
continually busy itself with providing for its needs, remains
permanently deprived of the knowledge which it should acquire; in
general, exercises to a very slight extent the organ of its
intelligence; preserves and propagates a multitude of prejudices
which enslave it, and cannot be as happy as those who, guiding it,
are themselves guided by reason and justice.

"As to the animals, besides the fact that they in descending order
have the brain less developed, they are otherwise proportionally
more limited in the means of exercising and of varying their
intellectual processes. They each exercise them only on a single or
on some special points, on which they become more or less expert
according to their species. And while their degree of organization
remains the same and the nature of their needs (_besoins_) does not
vary, they can never extend the scope of their intelligence, nor
apply it to other objects than to those which are related to their
ordinary needs.

"Some among them, whose structure is a little more perfect than in
others, have also greater means of varying and extending their
intellectual faculties; but it is always within limits circumscribed
by their necessities and habits.

"The power of habit which is found to be still so great in man,
especially in one who has but slightly exercised the organ of his
thought, is among animals almost insurmountable while their physical
state remains the same. Nothing compels them to vary their powers,
because they suffice for their wants and these require no change.
Hence it is constantly the same objects which exercise their degree
of intelligence, and it results that these actions are always the
same in each species.

"The sole acts of variation, _i.e._, the only acts which rise above
the limits of habits, and which we see performed in animals whose
organization allows them to, are _acts of imitation_. I only speak
of actions which they perform voluntarily or freely (_actions qu'ils
font de leur plein gré_).

"Birds, very limited in this respect in the powers which their
structure furnishes, can only perform acts of imitation with their
vocal organ; this organ, by their habitual efforts to render the
sounds, and to vary them, becomes in them very perfect. Thus we know
that several birds (the parrot, starling, raven, jay, magpie, canary
bird, etc.) imitate the sounds they hear.

"The monkeys, which are, next to man, the animals by their structure
having the best means to this end, are most excellent imitators, and
there is no limit to the things they can mimic.

"In man, infants which are still of the age when simple ideas are
formed on various subjects, and who think but little, forming no
complex ideas, are also very good imitators of everything which they
see or hear.

"But if each order of things in animals is dependent on the state
of organization occurring in each of them, which is not doubted,
there is no occasion for thinking that in these same animals the
order which is superior to all the others in organization is
proportionally so also in extent of means, invariability of actions,
and consequently in intellectual powers.

"For example, in the mammals which are the most highly organized,
the _Quadrumana_, which form a part of them, have, besides the
advantages over other mammals, a conformation in several of their
organs which considerably increases their powers, which allows of a
great variability in their actions, and which extends and even makes
predominant their intelligence, enabling them to deal with a greater
variety of objects with which to exercise their brain. It will
doubtless be said: But although man may be a true mammal in his
general structure, and although among the mammals the _Quadrumana_
are most nearly allied to him, this will not be denied, not only
that man is strongly distinguished from the _Quadrumana_ by a great
superiority of intelligence, but he is also very considerably so in
several structural features which characterize him.

"First, the occipital foramen being situated entirely at the base of
the cranium of man and not carried up behind, as in the other
vertebrates, causes his head to be posed at the extremity of the
vertebral column as on a pivot, not bowed down forward, his face not
looking towards the ground. This position of the head of man, who
can easily turn it to different sides, enables him to see better a
larger number of objects at one time, than the much inclined
position of the head of other mammals allows them to see.

"Secondly, the remarkable mobility of the fingers of the hand of
man, which he employs either all together or several together, or
each separately, according to his pleasure, and besides, the sense
of touch highly developed at the extremity of these same fingers,
enables him to judge the nature of the bodies which surround him, to
recognize them, to make use of them--means which no other animals
possess to such a degree.

"Thirdly, by the state of his organization man is able to hold
himself up and walk erect. He has, for this attitude which is
natural to him, large muscles at the lower extremities which are
adapted to this end, and it would thus be as difficult to walk
habitually on his four extremities as it would be for the other
mammals, and even for the _Quadrumana_, to walk so habitually erect
on the soles of their feet.

"Moreover, man is not truly quadrumanous; for he has not, like the
monkeys, an almost equal facility in using the fingers of his feet,
and of seizing objects with them. In the feet of man the thumbs are
not in opposition to the other fingers to use in grasping, as in
monkeys, etc.

"I appreciate all these reasons, and I see that man, although near
the _Quadrumana_, is so distinct that he alone represents a separate
order, belonging to a single genus and species, offering, however,
many different varieties. This order may be, if it is desired, that
of the _Bimana_.

"However, if we consider that all the characteristics which have
been cited are only differences in degree of structure, may we not
suppose that this special condition of organization of man _has been
gradually acquired at the close of a long period of time, with the
aid of circumstances which have proved favorable?_[195] What a
subject for reflection for those who have the courage to enter into
it!

"If the _Quadrumana_ have not the occipital opening situated
directly at the base of the cranium as in man, it is assuredly much
less raised posteriorly than in the dog, cat, and all the other
mammals. Thus they all may quite often stand erect, although this
attitude for them is very irksome.

"I have not observed the situation of the occipital opening of the
jacko or orang-outang (_Simia satyrus_ L.); but as I know that this
animal almost habitually walks erect, though it has no strength in
its legs, I suppose that the occipital foramen is not situated so
far from the base of the skull as in the other _Quadrumana_.

"The head of the negro, less flattened in front than that of the
European man, necessarily has the occipital foramen central.

"The more should the jacko contract the habit of walking about, the
less mobility would he have in his toes, so that the thumbs of the
feet, which are already much shorter than the other digits, would
gradually cease to be placed in opposition to the other toes, and to
be useful in grasping. The muscles of its lower extremities would
acquire proportionally greater thickness and strength. Then the
increased or more frequent exercise of the fingers of its hands
would develop nervous masses at their extremities, thus rendering
the sense of touch more delicate. This is what our train of
reasoning indicates from the consideration of a multitude of facts
and observations which support it."[196]

The subject is closed by a quotation from Grandpré on the habits of the chimpanzee. It is not of sufficient importance to be here reproduced.

Seven years after the publication of these views, Lamarck again returns to the subject in his _Philosophie zoologique_, which we translate.

"_Some Observations Relative to Man_.

"If man were distinguished from the animals by his structure alone,
it would be easy to show that the structural characters which place
him, with his varieties, in a family by himself, are all the product
of former changes in his actions, and in the habits which he has
adopted and which have become special to the individuals of his
species.

"Indeed, if any race whatever of _Quadrumana_, especially the most
perfect, should lose, by the necessity of circumstances or from any
other cause, the habit of climbing trees, and of seizing the
branches with the feet, as with the hands, to cling to them; and if
the individuals of this race, during a series of generations, should
be obliged to use their feet only in walking, and should cease to
use their hands as feet, there is no doubt, from the observations
made in the preceding chapter, that these _Quadrumana_ would be
finally transformed into _Bimana_, and that the thumbs of their feet
would cease to be shorter than the fingers, their feet only being of
use for walking.

"Moreover, if the individuals of which I speak were impelled by the
necessity of rising up and of looking far and wide, of endeavoring
to stand erect, and of adopting this habit constantly from
generation to generation, there is no doubt that their feet would
gradually and imperceptibly assume a conformation adapted for an
erect posture, that their legs would develop calves, and that these
creatures would not afterwards walk as they do now, painfully on
both hands and feet.

"Also, if these same individuals should cease using their jaws for
biting in self-defence, tearing or seizing, or using them like
nippers in cutting leaves for food, and should they only be used in
chewing food, there is no doubt that their facial angle would become
higher, that their muzzle would become shorter and shorter, and that
in the end this being entirely effaced, their incisor teeth would
become vertical.

"Now supposing that a race of _Quadrumana_, as for example the most
perfect, had acquired, by habits constant in every individual, the
structure I have just described, and the power of standing erect and
of walking upright, and that as the result of this it had come to
dominate the other races of animals, we should then conceive:

"1. That this race farther advanced in its faculties, having arrived
at the stage when it lords it over the others, will be spread over
the surface of the globe in every suitable place;

"2. That it will hunt the other higher races of animals and will
struggle with them for preëminence (_lui disputer les biens de la
terre_) and that it will force them to take refuge in regions which
it does not occupy;

"3. That being injured by the great multiplication of closely allied
races, and having banished them into forests or other desert places,
it will arrest the progress of improvement in their faculties, while
its own self, the ruler of the region over which it spreads, will
increase in population without hindrance on the part of others, and,
living in numerous tribes, will in succession create new needs which
should stimulate industry and gradually render still more perfect
its means and powers;

"4. That, finally, this preëminent race having acquired an absolute
supremacy over all the others, there arose between it and the
highest animals a difference and indeed a considerable interval.

"Thus the most perfect race of _Quadrumana_ will have been enabled
to become dominant, to change its habits as the result of the
absolute dominion which it will have assumed over the others, and
with its new needs, by progressively acquiring modifications in its
structure and its new and numerous powers, to keep within due limits
the most highly developed of the other races in the state to which
they had advanced, and to create between it and these last very
remarkable distinctions.

"The Angola orang (_Simia troglodytes_ Lin.) is the highest animal;
it is much more perfect than the orang of the Indies (_Simia
satyrus_ Lin.), which is called the orang-outang, and, nevertheless,
as regards their structure they are both very inferior to man in
bodily faculties and intelligence. These animals often stand erect;
but this attitude is not habitual, their organization not having
been sufficiently modified, so that standing still (_station_) is
painful for them.

"It is known, from the accounts of travellers, especially in regard
to the orang of the Indies, that when immediate danger obliges it to
fly, it immediately falls on all fours. This betrays, they tell us,
the true origin of this animal, since it is obliged to abandon the
alien unaccustomed partially erect attitude which is thrust upon it.

"Without doubt this attitude is foreign to it, since in its change
of locality it makes less use of it, which shows that its
organization is less adapted to it; but though it has become easier
for man to stand up straight, is the erect posture wholly natural to
him?

"Although man, who, by his habits, maintained in the individuals of
his species during a great series of generations, can stand erect
only while changing from one place to another, this attitude is not
less in his case a condition of fatigue, during which he is able to
maintain himself in an upright position only during a limited time
and with the aid of the contraction of several of his muscles.

"If the vertebral column of the human body should form the axis of
this body, and sustain the head in equilibrium, as also the other
parts, the man standing would be in a state of rest. But who does
not know that this is not so; that the head is not articulated at
its centre of gravity; that the chest and stomach, as also the
viscera which these cavities contain, weigh heavily almost entirely
on the anterior part of the vertebral column; that the latter rests
on an oblique base, etc.? Also, as M. Richerand observes, there is
needed in standing a force active and watching without ceasing to
prevent the body from falling over, the weight and disposition of
parts tending to make the body fall forward.

"After having developed the considerations regarding the standing
posture of man, the same savant then expresses himself: 'The
relative weight of the head, of the thoracic and abdominal viscera,
tends therefore to throw it in front of the line, according to which
all the parts of the body bear down on the ground sustaining it; a
line which should be exactly perpendicular to this ground in order
that the standing position may be perfect. The following fact
supports this assertion: I have observed that infants with a large
head, the stomach protruding and the viscera loaded with fat,
accustom themselves with difficulty to stand up straight, and it is
not until the end of their second year that they dare to surrender
themselves to their proper forces; they stand subject to frequent
falls and have a natural tendency to revert to the quadrupedal
state.' (_Physiologie_, vol. ii., p. 268.)

"This disposition of the parts which cause the erect position of
man, being a state of activity, and consequently fatiguing, instead
of being a state of rest, would then betray in him an origin
analogous to that of the mammals, if his organization alone should
be taken into consideration.

"Now in order to follow, in all its particulars, the hypothesis
presented in the beginning of these observations, it is fitting to
add the following considerations:

"The individuals of the dominant race previously mentioned, having
taken possession of all the inhabitable places which were suitable
for them, and having to a very considerable extent multiplied their
necessities in proportion as the societies which they formed became
more numerous, were able equally to increase their ideas, and
consequently to feel the need of communicating them to their
fellows. We conceive that there would arise the necessity of
increasing and of varying in the same proportion the _signs_ adopted
for the communication of these ideas. It is then evident that the
members of this race would have to make continual efforts, and to
employ every possible means in these efforts, to create, multiply,
and render sufficiently varied the _signs_ which their ideas and
their numerous wants would render necessary.

"It is not so with any other animals; because, although the most
perfect among them, such as the _Quadrumana_, live mostly in troops,
since the eminent supremacy of the race mentioned they have remained
stationary as regards the improvement of their faculties, having
been driven out from everywhere and banished to wild, desert,
usually restricted regions, whither, miserable and restless, they
are incessantly constrained to fly and hide themselves. In this
situation these animals no longer contract new needs, they acquire
no new ideas; they have but a small number of them, and it is always
the same ones which occupy their attention, and among these ideas
there are very few which they have need of communicating to the
other individuals of their species. There are, then, only very few
different _signs_ which they employ among their fellows, so that
some movements of the body or of certain of its parts, certain
hisses and cries raised by the simple inflexions of the voice,
suffice them.

"On the contrary, the individuals of the dominant race already
mentioned, having had need of multiplying the _signs_ for the rapid
communication of their ideas, now become more and more numerous,
and, no longer contented either with pantomimic signs or possible
inflexions of their voice to represent this multitude of signs now
become necessary, would succeed by different efforts in forming
_articulated sounds_: at first they would use only a small number,
conjointly with the inflexions of their voice; as the result they
would multiply, vary, and perfect them, according to their
increasing necessities, and according as they would be more
accustomed to produce them. Indeed, the habitual exercise of their
throat, their tongue, and their lips to make articulate sounds, will
have eminently developed in them this faculty.

"Hence for this particular race the origin of the wonderful power of
_speech_; and as the distance between the regions where the
individuals composing it would be spread would favor the corruption
of the signs fitted to express each idea, from this arose the origin
of languages, which must be everywhere diversified.

"Then in this respect necessities alone would have accomplished
everything; they would give origin to efforts; and the organs fitted
for the articulation of sounds would be developed by their habitual
use.

"Such would be the reflections which might be made if man,
considered here as the preëminent race in question, were
distinguished from the animals only by his physical characters, and
if his origin were not different from theirs."

This is certainly, for the time it was written, an original, comprehensive, and bold attempt at explaining in a tentative way, or at least suggesting, the probable origin of man from some arboreal creature allied to the apes. It is as regards the actual evolutional steps supposed to have been taken by the simian ancestors of man, a more detailed and comprehensive hypothesis than that offered by Darwin in his _Descent of Man_,[197] which Lamarck has anticipated. Darwin does not refer to this theory of Lamarck, and seems to have entirely overlooked it, as have others since his time. The theory of the change from an arboreal life and climbing posture to an erect one, and the transformation of the hinder pair of hands into the feet of the erect human animal, remind us of the very probable hypothesis of Mr. Herbert Spencer, as to the modification of the quadrumanous posterior pair of hands to form the plantigrade feet of man.

FOOTNOTES:

[195] Author's italics.

[196] "How much this unclean beast resembles man!"--_Ennius_.

"Indeed, besides other resemblances the monkey has mammæ, a clitoris, nymphs, uterus, uvula, eye-lobes, nails, as in the human species; it also lacks a suspensory ligament of the neck. Is it not astonishing that man, endowed with wisdom, differs so little from such a disgusting animal!"--_Linnæus_.

[197] Vol. i., chapter iv., pp. 135-151; ii., p. 372.