In philosophy, the term anti-realism is use to describe any position involving either the denial of an objective reality of entities of a certain type or the denial that verification-transcendent statements about a type of entity are either true or false. This latter construal is sometimes expressed by saying "there is no fact of the matter as to whether or not P." Thus, we may speak of anti-realism with respect to other minds, the past, the future, universals, mathematical entities (such as natural numbers), moral categories, the material world, or even thought. The two construals are clearly distinct and often confused. For example, an "anti-realist" who denies that other minds exist (i. e., a solipsist) is quite different from an "anti-realist" who claims that there is no fact of the matter as to whether or not there are unobservable other minds (i. e., a logical behaviorist).