To reify is to treat as a thing. To describe philosophers as reifying is usually to charge that they are misled by verbal form into thinking simply because some noun has a use, there must be something to which it refers. Thus Platonists are charged with reifying numbers or universals, and people are supposed to have improperly reified great varieties of things, including sets, infinite collections, finite things, sensations, physical objects, the future, the past, the possible, or the will of the people. The charge is itself not entirely transparent, and the fault these philosophies commit may more helpfully be put as treating things of one type as if they were things of another. See also ontology, realism/anti-realism.
Philosophy dictionary. Academic. 2011.