Also called atomic theory. Philosophy. the theory that minute, discrete, finite, and indivisible elements are the ultimate constituents of all matter.
2.
Psychology. a method or theory that reduces all psychological phenomena to simple elements.
Origin
1670-80
Related forms
atomist, noun
atomistic, atomistical, adjective
atomistically, adverb
British Dictionary definitions for atomism
atomism
/ˈætəˌmɪzəm/
noun
1.
an ancient philosophical theory, developed by Democritus and expounded by Lucretius, that the ultimate constituents of the universe are atoms See atom (sense 3)
2.
any of a number of theories that hold that some objects or phenomena can be explained as constructed out of a small number of distinct types of simple indivisible entities
any theory that holds that an understanding of the parts is logically prior to an understanding of the whole Compare holism (sense 3)
3.
(psychol) the theory that experiences and mental states are composed of elementary units