Apperception is closely related to association. Association, according to Wundt, furnishes all the possible connections of ideas; apper ception decides which of the possibilities shall be realized. Thus the idea a may be associa tively connected with a, b, r, and d, but apper ception may bring it about that, in a given ease of the arousal of x, only b appears in attention. This process of choice, of the enhancement of one out of several ideas, together with the feel ing of activity, differentiates apperception from association. Apperceptive connections them selves may be either simultaneous or successive. The former are subdivided into (a) agglutina tions, (b) apperceptive fusions, and (e) con cepts. (See ABSTRACTION.) The judgment is typical of the successive form of apperceptive connections. Stout defines apperception as the "process by which a mental system appropriates a new element, or otherwise receives fresh de termination." Great stress is laid upon the "preformed mental system," which is regarded as an organic whole, not (as by Herbart) more apperception-mass of presentations. By its reaction upon the further processes of attention, it gives us the clew to the problems of mental growth and mental organization. Stout further introduces the ideas of "negative" and "de structive" apperception. Negative appercep
tion is a form in which the effort to appropriate a new element is unsuccessful; destructive ap perception is a form in which "one system by appropriating a new element wrests it from its preformed connection with another system." In each case there results some positive effect; former systems become modified or new' sys tems are developed. The early experimental in vestigations of apperception deal for the most part with the time-relations of the various fac tors involved; the later investigations have analyzed the conditions under which appercep tion occurs. Valuable results have been gained by a study of the apperception of ideas as con veyed by language (q.v.), both spoken and writ ten.
BIBLIOGRAPHY. Leibnitz, New Essays (New Bibliography. Leibnitz, New Essays (New York, 1896) ; Herbart, Text-Book in Psychology (New York, 1891) ; Stout, Analytic Psychology (London, 1896) ; Wundt, Grundziige der physio logischen Psychologie (Leipzig, 1893) ; Logik (Stuttgart, 1S93) ; and Outlines of Psychology (Leipzig, 1897). Experimental: Erdmann and Dodge, Psychalagische Untersuchungen iiber das Lesen auf experimenteller Grundlagc (Halle, 1898) ; Lange, Apperception: A Monograph on Psychology and Pedagogy (Boston, 1893). See KNOWLEDGE, THEORY OF; ASSOCIATION OF IDEAS; PSYCHOLOGY.