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 cla.s.ses.
"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 pa.s.sions 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 princ.i.p.al 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 a.s.sent 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 ma.s.s of brutish, ignorant men approach the animal, becoming a prey to the most absurd prejudices and constantly enslaved by their habits, this ma.s.s 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 circ.u.mstances 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 mult.i.tude 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 circ.u.mstances, the mult.i.tude, 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 mult.i.tude 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 circ.u.mscribed 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 gre_).
"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 att.i.tude 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 circ.u.mstances 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 a.s.suredly much less raised posteriorly than in the dog, cat, and all the other mammals. Thus they all may quite often stand erect, although this att.i.tude 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 ma.s.ses at their extremities, thus rendering the sense of touch more delicate. This is what our train of reasoning indicates from the consideration of a mult.i.tude of facts and observations which support it."[196]
The subject is closed by a quotation from Grandpre 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 circ.u.mstances 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 a.s.sume 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 preeminence (_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 preeminent 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 a.s.sumed 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 att.i.tude 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 att.i.tude which is thrust upon it.
"Without doubt this att.i.tude 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 att.i.tude 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.