48 SCIENTIFIC CATALOGUE. 



is devoted to the general principles of philosophy ; the second aims at 

 vindicating a priori (on principles for which the first volume has 

 contended) the essential doctrines of Christianity. The work is 

 divided into four parts: I. "On the Intellectual Facilities and 

 processes which are concerned in the Investigation of Truth.' 1 ' 1 

 II. " Of First Principles in Philosophy." III. " Truths of 

 Religion." IV. " The Idea of Christianity in relation to Con~ 

 trover sial Philosophy" 



Huxley (Professor.) LAY SERMONS, ADDRESSES, 

 AND REVIEWS. See PHYSICAL SCIENCE CATALOGUE, 

 preceding. 



JevonS. Works by W. STANLEY JEVONS, M.A., Professor of 

 Logic in Owens College, Manchester : 



THE SUBSTITUTION OF SIMILARS, the True Principle of 

 Reasoning. Derived from a Modification of Aristotle's Dictum. 

 Fcap. 8vo. 2s. 6d. 



" All acts of reasoning" the author says, "seem to me to be dif- 

 ferent cases of one uniform process, which may perhaps be best 

 described as the substitution of similars. This phrase clearly 

 expresses that familiar mode in which we continually argue by 

 analogy from like to like, and take one thing as a representative 

 of another. The chief difficulty consists in showing that all the 

 forms of the old logic, as well as the fundamental rnks of mathe- 

 matical reasoning, may be explained upon the same principle; and 

 it is to this difficult task I have devoted the most attention. Should 

 my notion be true, a vast mass of technicalities may be swept from 

 our logical text-books and yet the small remaining part of logical 

 doctrine ivitl prove far more useful than all the learning of the 

 Schoolmen." Prefixed is apian of a new reasoning machine, the 

 Logical Abacus, the construction and working of which is fully 

 explained in the text and Appendix. "Mr. Jevons 1 book is very 

 clear and intelligible, and quite worth consulting." Guardian. 



ELEMENTARY LESSONS IN LOGIC. See EDUCATIONAL 

 CATALOGUE. 



Maccoll. THE GREEK SCEPTICS, from Pyrrho to Sextus. 

 An Essay which obtained the Hare Prize in the year 1868. By 



