developed out of debates over the
problem of universals.
Universals are terms or properties that can be applied to many things, such as "red", "beauty", "five", or "dog". Realism in this context, contrasted with
conceptualism and
nominalism, holds that such universals really exist, independently and somehow prior to the world. Moderate Realism holds that they exist, but only insofar as they are instantiated in specific things; they do not exist
separately from the specific thing. Conceptualism holds that they exist, but only in the mind, while nominalism holds that universals do not "exist" at all but are no more than words (
flatus vocis) that describe specific objects.