WORKS ON PSYCHOLOGY. THE PSYCHOLOGY OF ATTENTION. By PROFESSOR TH. RIBOT. Fourth edition. Pages, 121. Cloth, 75 cents. (3s. 6d.) THE DISEASES OF PERSONALITY. By PROF. TH. RIBOT. Third edition. Pages, 157. Cloth, 75 cents. (3s. 6d.) THE DISEASES OF THE WILL. By PROF. TH. RIBOT. Second edition. Pages, vi, 121. Cloth, 75 cents. (3s. 6d.) THE EVOLUTION OF GENERAL IDEAS. By PROF. TH. RIBOT. Pages, 231. Cloth, $1.25. (6s. 6d.) THE PSYCHIC LIFE OF MICRO-ORGANISMS. By DR. ALFRED BINET. Pages, xii, 120. Cloth, 75 cents. (3s. 6d.) ON DOUBLE CONSCIOUSNESS. By DR. ALFRED BINET. Third Edition. Pages, 93. Paper, 15 cents. (9d.) THE PSYCHOLOGY OF REASONING. By DR. ALFRED BINET. Pages, 193. Cloth, 75 cents. (3s. 6d.) THE SOUL OF MAN. By DR. PAUL CARUS. With 152 cuts and diagrams. Pages, xvi, 458. Cloth, $3.00. (15s.) CONTRIBUTIONS TO THE ANALYSIS OF THE SENSATIONS. By PROF. ERNST MACH. Pages, xi, 208. Cuts, 37. Cloth, $1.25. (6s. 6d.) ON MEMORY, AND THE SPECIFIC ENERGIES OF THE NERVOUS SYSTEM. By EWALD HERING. Second edition. Pages, 50. Paper, 15 cents, (9d.) THREE INTRODUCTORY LECTURES ON THE SCIENCE OF THOUGHT. By PROF. F. MAX MÜLLER. Pages, vi, 128. Cloth, 75 cents. (3s. 6d.) THE OPEN COURT PUBLISHING COMPANY 324 DEARBORN ST., CHICAGO, ILL. LONDON: KEGAN PAUL, TRENCH, TRÜBNER & COMPANY THE EVOLUTION OF GENERAL IDEAS BY TH. RIBOT PROFESSOR IN THE COLLÈGE DE FRANCE AUTHORISED TRANSLATION FROM THE FRENCH BY FRANCES A. WELBY CHICAGO THE OPEN COURT PUBLISHING COMPANY LONDON: KEGAN PAUL, TRENCH, TRÜBNER & CO., LTD. 1899 COPYRIGHT BY THE OPEN COURT PUBLISHING CO. CHICAGO, U. S. A. 1899 _All rights reserved._ PREFACE. The principal aim of this work is to study the development of the mind as it abstracts and generalises, and to show that these two operations exhibit a perfect evolution: that is to say, they exist already in perception, and advance by successive and easily determined stages to the more elevated forms of pure symbolism, accessible only to the minority.