In Scientia (Rivista di Scienza) for May, 1914, the first
artilcle is by A. Einstein on the principle of relativity. It is only
fair, after the criticisms of Marcel Brillouin and Max Abraham,
that an article written by one of the chief advocates of the theory
should appear in Scientia. Einstein distinguishes two theories of
relativity: the theory in the "narrow sense" and that in the "wide
sense." If we refer a motion to a system of coordinates K, for
which the Newtonian equations are valid, any other system of

coordinates which is in a uniform motion of translation with respect to K can be substituted for K. The "principle of relativity in the narrow sense" is the hypothesis of the equivalence of all such systems of coordinates for the formulation of the laws of motion and of the general physical laws. Thus, the principle of relativity is as old as mechanics itself, and, from the point of view of experience, its validity could never be doubted. However, the electrodynamics of Maxwell and Lorentz leads to the conclusion that every luminous ray is propagated in the vacuum with a determined velocity c which is independent of the direction of propagation and the state of motion of the luminous source. This deduction seems to be inconsistent with the principle of relativity. But an exact analysis of the content of our spatial and temporal data has proved that this inconsistency is only apparent, since it rests on the following arbitrary hypotheses: (1) The assertion that two events taking place in different places are simultaneous, has a content independent of the choice of the system of reference; (2) The distance between the places where two events simultaneously take place is independent of the choice of the system of reference. If we give up these arbitrary hypotheses, the above principle of the constancy of the velocity of light, which results from the well-attested theory of Maxwell and Lorentz, becomes compatible with the principle of relativity. The theories of gravitation are not all, as Abraham stated, inconsistent with the principle of relativity. The second part of the article is devoted to the "theory of relativity in the wide sense," which has hitherto hardly been confirmed by experience, but to which Einstein has been led from his philosophical standpoint, and which may be regarded as a development, and not an abandonment of the former theory of relativity. Svante Arrhenius discusses the problem of the formation of the milky way. Filippo Bottazzi gives the first article of a study on the fundamental physiological activities, entitled "nervous activity and the elementary processes on which it is founded." J. Arthur Thomson discusses "Sex-characters" and gives a critical review of Kammerer's great work on the collection of experimental data on the origin, evolution and development of sex-characters. A. Meillet has a paper on the problem of the parentage of languages. The difficulty experienced in making all languages enter into the genealogical classification has led certain eminent linguists to take away from the principle of this classification its precision and rigor or to

apply it in an inexact manner. This article shows in how far a genealogical classification of languages is possible and useful, and what can be hoped from it. Roberto Michels writes on economy and politics. Aldo Mieli has a critical note on the precursors of Galileo, in which he gives an account of the researches of Pierre Duhem on the origins of Galilean dynamics in the Middle Ages. Jean Buridan, who was rector of the university of Paris from 1327 to 1347, had a very clear idea of what has been called, since Leibniz, vis viva. What he called "impetus" he determined by the multiplication of velocity, volume, and density, and explained the cause of the accelerated motion of falling bodies. Buridan also applied to the heavens the dynamics established for earthly motions. "Newton," says Duhem, "had an idea of mass which was not very different from that which Buridan defined." Other people dealt with in this note are Nicole Oresme, who died in 1382, and had anticipated Copernican astronomy and Cartesian geometry, and discovered the Galilean law according to which the space described by a uniformly accelerated body increases with the times; Albert de Saxe, who anticipated a well-known error of Galileo's; and Dominique Soto, who was born in 1494. It is interesting to notice that this work of Duhem's is referred to very fully in the additions to the last German edition of Mach's Mechanics. A supplementary volume containing these additions will shorty by issued by the Open Court Publishing Co., so as to make it possible to read these additions in a small volume separate from the English fourth edition, without the expense of buying a large new book. There is also, in Scientia, a general review by L. Suali on the history of Indian philosophy. There are various reviews of books and periodicals, a chronicle of recent and forthcoming events and French translations of English, German, and Italian articles.

In Mind for April, 1914, the first article is by C. Lloyd Morgan on "Are Meanings Inherited?", in which the author discusses recent publications by Stout and McDougall. Henry Rutgers Marshall has a short paper on "Psychic Function and Psychic Structure.” F. Melian Stawell puts a number of questions about Bertrand Russell's Problems of Philosophy (London and New York, 1912). Horace M. Kallen writes on "James, Bergson, and Traditional Metaphysics." C. I. Lewis had, in a paper of 1912, tried to show that "the present calculus of propositions, in the algebra of logic,

is to ordinary inference what a non-Euclidean geometry is to our space. In particular, it asserts the presence of implication relations whose existence in our world may be doubted." The purpose of this note is "to outline a 'Euclidean' calculus of propositions— that is, one which will be applicable throughout to our ordinary modes of inference and proof." Charles Mercier, continuing the discussion between various logicians as to whether inversion is a valid inference, decides that it is not, and has some amazing sneers at traditional logic. "For practical purposes," says he, "the syllogism is about as useful as an unreliable apparatus for converting new-laid eggs into stale ones." A sympathetic review, by Miss E. E. C. Jones, of Mercier's New Logic (London, Heinemann, 1912; Chicago, The Open Court Publishing Co.), is contained in this number of Mind. J. E. Turner makes some critical remarks on Bertrand Russell's treatment of sense-data and knowledge in his Problems. Many reviews of books and periodicals and other notes etc., follow.

In the Revue de Métaphysique et de Morale for May, 1914, there is a very thorough study, by D. Rouston of the moral philosophy of Frédéric Rauh. There is a reprodution of Maurice Cauelery's lecture before the Paris School of Advanced Social Studies on the nature of biological laws, in which the author concludes, like O. Bütschli, that we can only grasp that part of vital phenomena which can be explained physico-chemically, and we can say of both vitalism and mechanism: "By their fruits ye shall know them." Emile Bréhier writes on philosophy and myth. Edmond Laskine contributes the second and final part of his critical study of the transformations of law in the nineteenth century. Charles Dunan discusses the practical question of electoral rights. There is the usual supplement containing reviews of new books and periodicals, and other notes.

Φ

BOOK REVIEWS.

ENCYCLOPAEDIA OF THE PHILOSOPHICAL SCIENCES. Vol. I, Logic. By Arnold Ruge, Wilhelm Windelband and others. Translated by B. Ethel Meyer. London: Macmillan, 1913. Pp. 269. Price $2.00.

This is an English edition of the German encyclopedia of Windelband and Ruge, made under the direction of Sir Henry Jones. The present volume comprises articles from eminent thinkers of Europe and America which are intended to present the determining principle of their thought upon the subject of logic. The views of German logicians are represented by Windelband of Heidelberg, who treats very generally of the phenomenology of knowledge, methodology and the theory of knowledge. The logic of English speaking countries is represented not by Russell or Peirce but by Professor Royce of Harvard who deals particularly with the types of order and with the relation of logic as methodology to logic as the science of order. M. Couturat expresses embarrassment in representing French philosophy, first because he makes no claim to expressing the views of French philosophers on logic, and second because the theories he presents are due to authors of Italy, Germany and England and particularly not of France—though in thus disclaiming for France any part in the logistic movement he is unfair to the significance of his own work in this line. For this new type of logic he prefers the term "logistic" or "algorithmic logic" to the formerly prevalent "symbolic" or "mathematical" logic or the "algebra of logic." From the point of view of this modern logistic he explains the principles and methodology of the logic of propositions, of concepts and of relations, and the relation between logic and language.

Benedetto Croce of Naples, in treating of "The Task of Logic," disregards the claims of the logisticians on the ground that logistic while providing rules for practice cannot be a science, and he considers logic as essentially a science, but a philosophical as distinct from an empirical science. He says: "It is no part of its business to assist thought,-to further the progress of natural science, mathematics or any of the special sciences, to facilitate research or to simplify the art of disputation. It is a theory entirely devoted to the task of inquiring into the nature of thought, as exemplified in science as a whole and in the particular sciences."

Another Italian, Professor Enriques of Bologna, treats the problems of logic in a more representative and eclectic manner as the science of exact thinking. He summarizes logical principles, operations, concepts and relations, discussing also definition and deduction. He then analyzes briefly the validity of logical principles and the relation of logic to metaphysical thought.

In this volume Russia is represented by Nicolaj Losskij who writes on "The Transformation of the Concept of Consciousness in Modern Epistemology and its Bearing on Logic."