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118 rare exceptions, and that nothing like a general law of the descent of mental traits could be established in the field of mind. But this error must now be regarded as abandoned. With the establishment of heredity as a biological law, or in the field of life, the presumption immediately became strong that it must also hold in the field of psychological phenomena. From the metaphysical point of view in which mind is regarded as an abstraction detached from organization, the law of heredity would probably never have been arrived at; but modern scientific psychology, which regards psychical phenomena as rooted and based in vital phenomena, passes naturally to the question as one of the necessary correlations of the higher organic science. And so it has come about that this principle of inherited mental predispositions and character, from being universally discredited as a baseless doctrine, is now admitted as a great truth, and not only so, but as a truth which forms the corner-stone of the latest philosophy. Among the students of mind, there is an old and inveterate quarrel about the origin of our ideas—one school holding that they are intuitions existing in an abstract mental world, and independent of all experience; and another school holding that all ideas are derivable from the experience of individuals. Herbert Spencer has shown that there is a partial truth in both these views, and that they are capable of essential reconciliation through the principle of the evolution of faculties by inherited experience.

So prominent has this doctrine become in recent inquiry, and so profound is its importance, that there has been an imperative need of some work that should deal distinctly and broadly with the subject, and present its scientific aspects in a form suitable for popular study. Such a work we now have from Prof Ribot. Mr. Galton's work on "Hereditary Genius" is a valuable contribution to the subject, but it is very far from being complete in its exposition, and its main facts are presented in a form somewhat difficult for the reader to deal with. Prof. Ribot's work is systematic and full, taking up the subject under the four successive departments of the facts, the laws, the causes, and the consequences of heredity.

The following passage, from the conclusion of the work, will give an idea of the author's style, and of the method of his argument. In summing up all facts in favor of psychological heredity, he says:

"As regards specific characteristics" (i. e., those which distinguish one species from another), "heredity comes before us with the evidence of an axiom. In the physical, as in the moral order, every animal necessarily inherits the characteristics of its species. An animal which should possess, with the organism of its own species, the instincts of another, would be a monster in the psychological order. The spider can neither have the sensations nor perform the actions of the bee, nor the beaver those of the wolf. Just so in one and the same species, whether animal or human, the races preserve their psychical precisely as they do their physiological characteristics.... Under the specific form, then, mental heredity is unquestionable, and the only doubt possible would have reference to individual characteristics. We have shown, from an enormous mass of facts, that the cases of individual heredity are too numerous to be the result of mere chance, as some have held them to be. We have shown that all forms of mental activity are transmissible—instincts, perceptive faculties, imagination, aptitude for the fine arts, reason, aptitude for science and abstract studies, sentiments, passions, force of character. Nor are the morbid forms less transmissible than the normal, as we have seen in the case of insanity, hallucination, and idiocy."

The book consists of four parts, as we have remarked, under the headings indicated in the sub-title. In Part I. we have chapters on the Heredity of Instincts; of Sensorial Qualities; of Memory; of Imagination; of Intellect; of Sentiments and Passions; of Will; of Natural Character; of Morbid States. In Part II. the author devotes four chapters to a discussion of the Laws of Heredity, the titles being: "Are there Laws of Heredity?" the "Laws of Heredity;" "Essays in Statistics" (containing a criticism of Galton's great work);" Exceptions to the Law of Heredity." Part III. shows the dependence of psychological upon physiological heredity. In Part IV. we have chapters on "Heredity and the Law of Evolution;" "The Psychological Consequences of Heredity;" "Moral Consequences;" "Social Consequences."