The History of Biological Theories

Schleicher's arguments were approved by the natural- ists. Haeckel quoted them in his writings ; Lyell also re- ferred to them favourably in his Geological Age of Man, and Darwin gave them a friendly notice in his Descent of Man. Many philologists and philosophers agreed with this view, that speech had evolved in accordance with Darwin's principles. There were also several widely accepted theories which dealt with the origin of the capacity for speech. Darwin himself discussed the question ; he explained that speech began in the imitation of various sounds and of animal voices, and in the instinctive human cries. He pointed out that some monkeys (e.g. Hylobates agilis) can, in a certain sense 'sing', and he believed that man was once at the same stage of development, able to sing some musical cadence for the amusement of his mate, but other- wise without speech homo primigenius alalus. Gradually, from such song, articulate sounds developed, then words by means of which man could express his many and varying emotions.

Jaeger attempted to show the definite steps by which speech may have evolved from animal sounds (1888). These animal sounds begin as chance ones for example, the buzzing of a fly. They then become intentional for example, the chirruping of a grasshopper. This sound pro- duced at will this interjection is the first step in the development of language. A higher stage is represented by the call with which the male allures the female ; a still higher by the imitative song characteristic of many birds. Social life produced new sounds among animals, and so there was further progress. Speech, then, was originally a series of sounds expressing subjective conditions. It is still at this stage of development among the grasshoppers, the cicades, &c. It became a call ; then it passed beyond the merely subjective, and became an appeal to companions. Jaeger thinks the power some animals possess of pointing out noteworthy objects (a goose points towards a hawk) may be related to this power to call.

It was assumed that a still higher stage of development is represented by the 'pictorial word' used by primitive man when he begins to express his sensations by sounds, instead of by gestures only. So arose the roots of our words *ac', for example, was supposed originally to have ex- pressed pain. In another place Jaeger explained why animals so seldom produce varying tones and sounds. The lung in the act of expiration provides the necessary pre- liminary for the formation of sounds with definite nuances, whether spoken or sung; but the accompanying move- ments of the chest cavity are impossible to four-legged animals chest movements in these animals being affected by every motion of the fore-leg.

Similar theories were upheld by other philosophers in the eighties of last century. The views of Schleicher, the fantasies of Bopp and Jaeger, have long been abandoned. Philologists have given up the idea that the roots which they abstracted from various languages once existed as independent words. Schleicher's genealogical tree has only an historic interest, and no one now supports the view that languages were developed from inarticulate interjec- tions. The fundamental hypothesis itself that the study of language is applied natural history was supplanted in the eighties. The reaction came from workers who believed that speech must be a product of the human intellect and that the methods of the naturalists, deduced from a study of the body, are therefore not applicable to it.

The new philosophy exerted a twofold influence upon educational ideas. Firstly, the evolutionists claimed that scientific methods and the results of scientific discovery must be taught in the schools ; secondly, that all our views about life must be revolutionized. Spencer, Huxley, von Baer, and a host of other investi- gators urged that the schools should 'move with the times'. They would have abandoned the classical education in favour of the study of chemistry, physics, and natural history. In every country but most of all, perhaps, in France educational practice more or less adapted itself to the new theories. This movement is, however, probably now on the wane, although it still has many defenders.

The idea that the man is a part of society and of the race, and that the health of the race depends upon the health of each of its units, also affected pedagogy. The children must be kept healthy if the future generations are to be strong. Evolutionary philosophy in the form of Haeckel's funda- mental biogenetic law brought about further changes in educational theory. Spencer, Preyer, and others thought that man recapitulates the stages through which his fore- fathers have passed, not only during his embryonic life, not only during his childhood, but through all the stages of his intellectual development. Some saw in this a reason for teaching the classics. Since antiquity represents a stage in the development of the human spirit, the study of the classics must be a necessary part of the education of the young. l The physiologist Preyer deduced his child psycho- logy from Haeckel's law ; the study of the mental processes of the child will enable us to picture the former mentality of man. This new science was accepted by Darwin himself, by Romanes, and particularly by the American psychologist Baldwin. Pedagogic ideas were further influenced by the new views concerning heredity and natural selection. 'Given the inherited advantages and disadvantages of a race, in how far can this inheritance be altered by educa- tion ?' This, affirmed Guyau, was the problem which the educationalists must attack, and he claimed that educa- tional practice should be based on the physiological and ethical laws of racial culture.

Fouillee agreed with him and repeated, 'The object of education is to produce new inheritable qualities, which shall be advantageous to the race, both physically and psychically'. He called in Natural Selection, though in a modified meaning of the term, to help in the process. He thought of it not as selection in the struggle for existence only but as selection during a struggle for the improve- ment of life in its physical, intellectual, and moral aspects. Genetic ideas also invaded pedagogic practice. Since everything has been evolved, Spencer's idea was adopted

1 Herbart, and his pupil Ziller, had already affirmed that every single man, in the course of his intellectual development, repeats the various stages of cultural development through which the whole human race has passed. that pupils would best understand their teacher if he ex- plained the object of study genetically. Thus, for instance, in the study of natural history, the older method that of beginning with man and ending with microscopic organisms was declared to be unsound. Then it was thought that the teacher should advance from the known to the unknown, but now it was held that instruction should begin with the amoeba, with the single cell from which all life has evolved. A lecture on the brain, for example, should begin with the amoeba, pass to a ganglian cell, then to the brains of fish, frog, rabbit, and ape, to end finally with the human brain.

It was under the stimulus of Darwin's theory that John Dewey, an American philosopher, formulated his pedagogic system. The influence of this system spread through the whole civilized world, but it would be beyond the range of this book to discuss this subject more fully. Darwinism exerted a profound influence on all our ideas about the nature of human society and human history. At the beginning of the nineteenth century the German philosopher Hegel, following the example of his fellow countryman Herder, had conceived of a universe in evolu- tion : starting as a subconscious God, and evolving into matter in motion, into the world of plants and animals, into human society, into art, science and the state, into religion. This philosophy exerted a profound influence, especially upon historians and sociologists.

When, in addition to this, Comte and Buckle propound- ed the ideal of 'scientific' history by the study of which it should be possible for the historian to enunciate definite laws which underlie human affairs the foundations were laid for a Darwinian interpretation of history and of sociology. Buckle, in a book that appeared at the same time as Darwin's Origin of Species, suggested that writers of history should first collect and analyse their facts, then deduce from these facts general formulae, and that their

final endeavour should be to formulate universal laws, after the manner of a Kepler or a Newton. Since there is always a mutual interaction between man and nature, the conditions of both must be studied. The historian must not neglect to ascertain the influence of food, of climate, of the soil, of the general environment. Buckle, analysing the history of English civilization accord- ing to these principles, came to the conclusion that it consisted simply in a continual conquest of nature by man, and in the ever-increasing intellectual training resulting from this endeavour to overcome natural difficulties.

The influence of natural science on historical thought and historical writing was very much heightened by Buckle's book. Comte's attempt to draft a hierarchy of the sciences exerted an equally strong influence. He placed sociology above biology, and recommended that biological methods should be introduced into sociology. Taine, following in his footsteps, made it his task to win acceptance for biological concepts in the study of history. These investigators only linked up history and biology in the most general way. But there were a whole series of workers who tried to introduce Darwinism into the details of historical work. Of these Herbert Spencer was leader ; he pictured society as an organism, and as, according to the materialistic theory, the living organism is merely an aggregate of cells, so is society according to Spencer an aggregate of men or of families. Further, society, like the organism, has a definite structure. Among civilized peoples the ectoderm is composed of the warriors, the endoderm of the women and slaves who attend to the household. As the nervous system is developed from ectoderm, so from the warrior caste are derived the rulers of society. Just as mesoderm develops later between these embryonic layers, so in human society there arises between the warrior and the producing classes the class devoted to trade. A peace- loving government is to be compared with the sympathetic nervous system ; a war-like one, on the other hand, with brain and spinal cord. The struggle for existence and its

consequent natural selection occur both in nature and in society ; the progress of a society consists in a continual better-fitting of its individuals to the conditions prevailing in that society. As interpreted by Spencer, sociology became strongly affected by Darwinism. Karl Marx and Engels, in particu- lar, sought to introduce Darwinian theories into their extremely materialistic sociological philosophy. The social democrats looked with favour upon the Darwinian theory, since in its materialistic and anti- clerical tendencies it coincided with their ideas concern- ing the universe. Both Karl Marx and Engels, who had attempted to give a new and materialistic interpretation of Hegel's philosophical history, showed great reverence for science. In this they were like most of the philosophers of their time ; these accepted Darwin's teaching as un- questioningly as if it consisted of actual, well-established scientific facts. Later on Socialists both read and wrote many popular books on the subject of evolution.

When Virchow pointed out the connexion between social democracy and the teaching of the evolutionists, some Darwinians made a great effort to emphasize the points in which the two theories seemed to be logically opposed. Oscar Schmidt, a follower of Haeckel ( 1 878), de- clared that Socialism and Communism, movements which strive for the equality of man, only occur in Nature among social animals in the lowest stages of development. The more advanced life becomes, the more is this undifferen- tiated equality destroyed, and the more is the egoism of the individual enabled to gain the upper hand. The view of evolution expressed by Marx and Engels, continued Schmidt, is quite different from that held by Darwin. They believe, as did Hegel, in something abstract, in an idea of evolution. Darwin is only concerned with actual events, with their causes and their results. Further, this Socialistic ideal of equality contradicts the facts of natural

selection; for natural selection demands an inequality between organisms as the essential factor underlying every advance. Schmidt's explanation was doubtless the correct one, and Darwin, Huxley, Haeckel, and others were voicing their innermost convictions when they asserted that their views were contrary to those of the Socialists. Neverthe- less, we can hardly regard the friendly reception given by the Socialists to Darwinism as a mere chance. At the present time the view usually held is that the evolutionary theory is an aristocratic one; the stronger wins in the struggle for existence, and to secure his survival hecatombs of his weaker brethren are sacrificed. There is much, how- ever, to be said against this view.

Firstly, the words 'aristocrat' and 'democrat' are being used here to denote a logical idea rather than anything in actual existence. Secondly, the idea of a selection of the best types forms, it is true, the nucleus of the Darwinian theory ; but we cannot regard this idea as a purely aristocratic one, for it does not contain that fundamental characteristic of aristo- cratic thought the picture of an individual who gains his ascendancy by bis own powers. The struggle for existence is merely Darwin's name for a blind mechanical process.

Thirdly, the theory contains one completely non- aristocratic conception, that of the influence of the en- vironment upon the organism. Fourthly, we note that the general ideas of Darwin, of Spencer, and of Haeckel, the founders of Darwinism, were much more nearly democratic than aristocratic. Remember Darwin's intense objection to giving pain to animals; his mechanistic philosophy ; his comparison of men and monkeys ; his most honourable condemnation of slavery ; his hope for the progress of mankind !

It is easy to understand why the leading Darwinists did not want to admit a connexion between their views and those of the Socialists. They looked upon the Socialists as a party dangerous to the State, and in this respect they were completely opposed to socialistic teaching. The Socialists, however, sensed the democratic background of the new philosophy ; they agreed with the Darwinists in their struggle with the Church and in their idealistic philosophy; they agreed also in their materialistic ideas concerning mankind. The fact that their leaders had begun as Hegelian idealists affected them little had not the materialists. Strauss and Feuerbach been his pupils ?

In our times conditions have completely altered. Nietsche introduced a strongly individualistic tendency into Darwinism, while, on the other hand, the theorists among the social democrats have no longer any very pro- found belief in either Darwinism or Materialism, nor indeed any special love for science. Modern Darwinism or at least that form of it preached by the eugenists may be regarded as an aristocratic theory. During the seventies in Germany there appeared a large number of poems, novels, and romances dealing with Darwinian themes ; the struggle for existence, the glorious future of mankind, the life of antediluvian man, and so on. The French naturalistic novel was written under a very strong Darwinian influence. As Darwin excluded idealism from biology, so did Zola wish to banish from the novel all domination of personality by the will, by reason, or by the ideal ; he tried to eliminate the soul, and to replace all these higher faculties by the action of instinct and of heredity. HaeckePs genealogical tree also reappeared in light litera- ture, when Zola ended his cycle of Rougon-Macquart novels with a table showing the descent of his heroes. Neurasthenia, drink, and sexual excesses (Dr. Pascal) had burdened them with such an unfortunate heredity that this could only lead to the downfall of the whole family.

Zola's ideal novelist was like Darwin's ideal naturalist. Darwin did not strive to understand Nature, as this might introduce a subjective element into science. Every theory must be quite impersonal it should merely supply us with a picture of what is actually happening in nature. In a similar manner Zola banished fantasy, and asked for nothing from the artist except facts arranged in the proper order. The hand of the writer was not to be noticed in his works ; he must not order the facts accord- ing to his will ; he is merely a recorder, and must give them free play. Interest in Zolaesque naturalism quickly faded, but interest in the doctrine of evolution survived.

Brunetiere led a bitter campaign in France against naturalism, leaning so far towards the Right that he almost landed in the Papal camp. Nevertheless he was a firm believer in evolution, and began his critical essays by assuming that literary tendencies are species, analogous to biological ones, which arise, develop the organs they re- quire, reach their height, then fall or become modified into new ones ! Darwinism exerted a great influence on the literature of other nations. This influence would obviously be modified in each land by the national character and the prevailing conditions. In England it manifested itself in a philosophy of very concrete ideas ; in Germany it became a creed, a scientific system; in France it appealed to the 'literati'; in America Darwin's friend Asa Gray upheld his views, but the teaching does not appear to have produced any very characteristic effects there ; in Italy the theory was taken up both by scientists and by popular writers. The Italians even cited some of their own fellow countrymen as 'forerunners' of Darwin.

In Russia Darwinism became a part of that stream of positivism and materialism which began to flood the country in the middle of the nineteenth century. Before that time intellectual Russia was under Hegel's influence. A strong reaction against idealism now set in, and natural science was called in to help in its overthrow. The words of Pisarev 1 one of the most important interpreters of 1 Quoted from Ovsjanniko-Kulikovskij's Istoria russkoj intelligence^ Moscow, 1 907, vol. ii, p. 374.

'To drive the common folk (profanum vulgus) out of the temple of Science does not suit the spirit of these times. An aristocracy of art is a most reprehensible phenomenon. A monopoly in science and education is the most dangerous of all monopolies. What sort of a doctrine is that, the very essentials of which are unintelligible to the masses ?' Pisarev held that such abstract subjects as philosophy and psychology merely represent an empty scholasticism, and that natural science must be presented so simply that ten-year-old children and uneducated peasants can under- stand it. 1

Such views gained a great deal of sympathy in Russia, and were supported by the translation of such materialistic writings as those of Vogt, Lange, and Biichner. Biichner's Kraft und Stoff was long banned in Russia. The works of Darwin, Spencer, Haeckel, Wallace, and Romanes were translated, and helped to forward the movement ; the translations of HaeckePswork were confiscated. 2 The desire in Russia was more for exact knowledge than merely for materialist doctrines. Liebig w r as praised as well as Vogt, von Baer as well as Haeckel. Some of the personalities of this time won fame even beyond the Russian border the two Kovaleskys (the palaeontologist and the embryo- logist), Cienkovsky, and Metchnikov among others.

Most schools of jurisprudence consider each man re- sponsible for his own acts. In the seventies Cesare Lom- broso, a professor at Turin, brought forward evidence that there are criminals in whom lawlessness is inborn; that such men are a class apart, showing many of the physi- cal and psychical characteristics of uncivilized man and of animal ancestors. These characters are therefore atavistic. The view of Paracelsus that the fool is a 'man who went wrong in the making', was expressed in a modern guise. Ferri, Lombroso's follower, distinguished between the criminal lunatic, the born criminal, the man who has acquired criminal habits, and the man who commits a crime of passion. Lombroso adopted this classification and asserted that the born criminal shows definite physical signs of degeneracy, among which are : pathological skull- formations; varying number of such organs as nipples, fingers, and teeth; irregularities in the convolutions of the brain. Ape-like characters found among criminals are, in particular, a very small brain ; thick, heavy eyebrows ; the continuation forwards of the processus jugalis; large eyesockets; protruding teeth; very heavy jaws; a peculiar shape of the ear-muscles.

In these, and in many other characters, the criminal is supposed to resemble the monkey in structure. He is less sensitive to pain than normal, and likes to be tattooed; he is often left-handed ; when his arms are horizontally extended, the length from finger-tip to finger-tip is greater than his height ; his body is hairy ; his sex less well-defined ; his heart less easily stimulated; wounds less painful. Mentally he is on the plane of uncivilized man. Hence we get criminal prostitution, cannibalism, cruelty, the blood feud, the dislike of honest work, the typical carelessness, moodiness, and conceit of the criminal. Lombroso affirmed that forty per cent, of all the inmates of prisons belong to this criminal type.

Many lawyers and doctors accepted Lombroso's views. Serious investigators do not now attach great importance to Lombroso's anatomical description of the criminal type, but many experienced lawyers and psychiatrists hold that some men are born with criminal tendencies. THE Catholic Church not only teaches definite re- ligious doctrines, it also gives a definite teaching concerning Nature. This consists of a mixture of ideas, taken partly from ancient Jewish natural history, and partly from the views of the Holy Fathers of the Church, interpreters of Galen and Aristotle. These ideas were once living. The words of Genesis, in which a Moses gave for the first time to his contemporaries his view of the world, were in his day truths as definite and as incon- trovertible as any of our truths of to-day ! At the time of their first enunciation, the teaching of St. Augustine, the truths of the Scholastics, represented convictions as firm and sure as our modern teaching of the origin of men from animals. It was not this truth, however, this deep per- sonal conviction of Her founders, that was upheld by the Church ; that living Truth, which cannot be expressed on paper, which only exists in man's deepest soul. The Church defended the mere words the words by which those thinkers, long dead, had sought to express their relation to the Universe. 'When we speak, we begin at once to err,' says the poet. But the Church made these fossilized words the very foundation of Her teaching.

Modern natural history has in part developed out of this Biblical natural history. The older 'biologies' were enumerations of the animals of Noah's Ark, or taken from St. John's Book of Revelation. Thus science began, and ever since it has been her constant endeavour to escape from these origins. To the men of the Renaissance, entering into a healthier relationship with nature, the fantastic animals and unnatural ideas of more remote times became mere empty words. Belief in Biblical natural history had long been abandoned, although the

Church had not freed itself from this antediluvian story indeed has not done so to this day. 1 She cannot free herself, for the Bible makes no distinction between theology and the philosophy of Nature ; both are depicted as equally true. Even if the Church did admit the falsity of some of its concrete teaching, what can the present-day naturalist say to angels, to saints, to the whole content of ecclesiastical dogma ? Nowhere, either in his facts, in his theories, or in his philosophy, does he find any point of contact with these dogmas.

The theologians themselves recognize this fact, but they do not admit that this is a failing of modern theology. They point out that this or that man has been able to reconcile theological teaching with exact science. This is certainly true. It is doubtless often true that 'thoughts can live peaceably next each other'. But they should not live 'next each other'. They should permeate each other, making a logical whole. His theology should be obvious in the theories and discoveries of the orthodox investigator. The saintly Kepler believed that the planets are moved by angels. When Kirchner first had the idea that water may occur on other planets, he at once asked himself whether Baptism with water from Venus would be valid. Napier, the discoverer of logarithms, discussed with equal earnestness those complicated properties of numbers, and the question whether migratory locusts may have been Mohammedans by religion. That was a science saturated with theology ; a science of honest conviction, a theology of honest conviction, pursued by investigators with honest convictions! Present-day theologians should demand an equal single-mindedness from their modern adherents. It is another question whether such a union of science and theology is possible to-day.