VORLESUNGEN ÜBER DIE MENSCHEN- UND THIERSEELE. By _Wilhelm Wundt_. Zweite umgearbeitete Auflage. Hamburg and Leipsic: Leopold Voss. 1892. The new edition of Wundt’s _Menschen- und Thierseele_ is one of the best existing general introductions to psychology. It preserves nearly the just mean between the purely introspective and abstract treatment and the substitution of physiology for psychology with which recent treatises have familiarised us. The author has completely rewritten the edition of 1863, which he regards as a youthful indiscretion (_Jugendsünde_)—retaining only such chapters as could be brought into harmony with his maturer views and with the developed science of psycho-physics that has taken the place of the _Zukunftsprogramm_ of thirty years ago. He has wisely omitted all the superficial and diffuse chapters on comparative psychology and ethnology which cumbered the original work; has silently ignored the fantastic speculations as to the identity of electricity and nerve-force (one of the worst of the aforesaid youthful sins); and practically abandoned (perhaps as too esoteric for popular exposition) the elaborate reduction of sensations and perceptions to unconscious judgments and inferences. The first thirteen or fourteen chapters offer a very clear and interesting résumé of the chief doctrines of the _Physiologische Psychologie_ in regard to sensations generally, their measurements and qualities, Weber’s and Fechner’s laws, the special sensations of color, hearing, and the muscular sense, and the problem of space perception. Following the plan of the original work in these chapters, the author aims less at completeness of statement than to present clearly the distinctive doctrines of modern psychology. In the treatment of certain themes, e. g. Fechner’s law, and the perception of space, he neglects, for the sake of clearness, qualifications of detail which the special student must look for in the larger work. The last sixteen chapters deal with the feelings, the will, consciousness, attention, association and apperception, conception, abnormal and animal psychology and instinct, concluding with two notable lectures on the “Freedom of the Will” and the “Immortality of the Soul.” It is to these chapters that we must look for Wundt’s general psychological and philosophical system. Profiting by recent criticisms he has here set forth his characteristic doctrines in so clear and definite a final statement that further misconception of them is hardly permissible. The remainder of this notice will be devoted to what is perhaps the most interesting question thus suggested: Wundt’s relation to the associationist psychology of Spencer on the one side, and to the younger German school of experimental psychologists on the other. Wundt ignores the Spencerian form of the associationist psychology, and the young psychologists do injustice to Wundt, neither side apparently condescending to read with attention the writings of the other.