in philosophy, position taken in the dispute over universals-words that can be applied to individual things having something in common-that flourished especially in late medieval times. Nominalism denied the real being of universals on the ground that the use of a general word (e.g., "humanity") does not imply the existence of a general thing named by it. The nominalist position did not necessarily deny, however, that there must be some similarity between the particular things to which the general word is applied. Thoroughgoing nominalists would withhold this concession, as Roscelin, a medieval nominalist, is said to have done. But unless such similarity is granted, the application of general words to particulars is made to appear entirely arbitrary. Such stricter forms of nominalism as existed in the Middle Ages can perhaps be viewed as reactions against Platonic realism, on which some enthusiasts, such as Guillaume de Champeaux, based the opinion that universals had real being. The realist position invited a defensive alliance between empiricism and nominalism; the most notable medieval example of such a synthesis was the work of William of Ockham.
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