the same way; and, what is still odder, when much excited she raised both her hands, with her fingers still moving, to the sides of her face, in exactly the same way as her father had done. Handwriting depends on several physical and mental habits, and we often see a great resemblance between the handwriting of a father and a son. Even those who have no great powers of observation must often have remarked this. 'Hofacker, in Germany, has remarked that handwriting is hereditary.' The same remark will apply to France; and it has even been asserted that English boys, when taught to write in France, naturally cling to their English manner of writing.'1 What is true of habits is also true of anomalies accidentally acquired, that they are transmissible. Thus a man whose right hand had suffered an injury had one of his fingers badly set. He had several sons, each of whom had that same finger crooked. (Blumenbach.) Artificial deformities, too, are transmissible. Three tribes in Peru-the Aymaras, the Huancas, and the Chinchas had each their own peculiar mode of deforming the heads of their children, and this deformity has since remained. The Esquimaux, says M. de Quatrefages, cut off the tails of the dogs they harness to their sledges; the pups are often born tailless. Notwithstanding these facts, the transmission of acquired modifications appears to be very restricted, even when occurring in both of the parents. A deaf-mute married to a deaf-mute has children who can both hear and speak. The necessity of performing circumcision on Jews shows that an acquired modification, often repeated, is not therefore hereditary. Deviations from a type, after having subsisted for generations, return to the normal state; so that many naturalists hold it as a rule that accidental modifications are not perpetuated. This is very different to the law formulated by Lamarck :'Whatever Nature has enabled individuals to gain or to lose, under the influence of circumstances to which their race has been long exposed, is preserved, by generation, for the new individuals 1 Darwin, Variation of Animals and Plants under Domestication, vol. ii. p. 6. Edition, 1868. which descend from them, provided the changes acquired are common to the two sexes, or to those which have produced new individuals.'1 Still, these two opposite opinions, both of which may be supported by facts, can be reconciled if we bear in mind that there are modifications which, by their very nature, are in antagonism with everything around them, and for which, in consequence, the conditions of existence grow more and more difficult; just as there are others which, when in conformity with everything around them, may become permanent by either natural or artificial selection : so that all things conspire to blot out the former class of modifications, and to perpetuate the latter. We shall meet this difficulty again, when treating of psychological heredity, and will there consider it more fully. We have now to speak of the last form of heredity-that of disease. This seems to have been observed from the foundation of the art of medicine-in all times, in every land, and in every nation. Even the Greek physicians recognized hereditary diseases (νόσοι κληρονομίκαι). And yet in modern times the heredity of disease has given rise to all manner of debates among medical men. It would be beyond our subject, and beyond our power, to discuss this point. It is enough to say that the question appears to be substantially settled by the fact that the sturdiest opponents of morbid heredity admit, if not the heredity of disease itself, at least the heredity of a disposition to it. In Dr. Lucas's work on Heredity will be found facts of all kinds, sufficiently numerous and sufficiently clear to warrant a conclusion. This hasty physiological sketch will show that the law of heredity influences every form of vital energy—a fact which is generally known and admitted. Is the same to be said with regard to the psychological aspect of the question? This we propose now to consider, and to begin with the study of the facts. 1 In regard to the physiological side of this controversy, see the Bulletins de la Société d'Anthropologie, tome i. p. 339, and particularly p. 551, seq.; tome ii., De l'Hérédité des Anomalies. CHAPTER I. HEREDITY OF INSTINCTS. I. WHEN We speak of instinct, our first difficulty is to define the term. Not to enumerate here all the various significations of the word as used in ordinary language, it is employed in at least three different senses even by naturalists and philosophers, whose language has to be more precise than that of other people. Sometimes instinct is intended to signify the automatic, almost mechanical, and probably unconscious action of animals, in pursuance of an object determined by their organization, and specific characters. Again, instinct is made synonymous with desire, inclination, propensity; as when we speak of good or evil instincts, a thievish or murderous instinct. Finally, we sometimes comprise under the term instinct all the psychological phenomena occurring in animals, and all forms of mental activity inferior to those of man. This latter signification of the word is plainly the result of our unwillingness to attribute intellect to brutes; and thus, contrary to all reason, we confound with blind and unconscious impulses the conscious acts which every animal performs under the guidance of its individual experience,1 and which, consequently, are analogous to those which, in our own case, we call intelligent or intellectual acts. Although, in our opinion, instinct and intelligence are one and the same, as we will try hereafter to show, and though the difference between them is one not of kind, but only of degree; still we will employ the word instinct here in its first signification only which alone we hold to be exact and in conformity with etymology. We must, for the sake of greater precision, begin with a good definition of this term; but, unfortunately, no such definition has yet 1 For instance, the act performed by a dog carried far from his home, when from among a score of roads he selects the one which will bring him back. |