Realism (philosophy)


 * For other meanings of the term "realism", see realism (disambiguation).

Contemporary philosophical realism, also referred to as metaphysical realism, is the belief in and allegiance to a reality that exists independently of observers. Realists believe that theories are successful because they have a correspondence to reality. That is, because the theoretical explanations in question have some correspondence to what actually exists.

Realists tend to believe that whatever we believe now is only an approximation of reality and that every new observation brings us closer to understanding reality. Realists tend to embrace what they believe is actually real, despite how unattractive reality itself may be. Most realists arrive at their understanding of reality through critical thinking.

Debates about realism
Despite the seeming straightforwardness of the realist position, in the history of philosophy there has been continuous debate about what is real. In addition, there has been significant evolution in what is meant by the term "real".

The oldest use of the term comes from medieval interpretations and adaptations of Greek philosophy. In this medieval "scholastic" philosophy, however, "realism" meant something different -- indeed, in some ways almost opposite -- from what it means today. In medieval philosophy, realism is contrasted with "conceptualism" and "nominalism". The opposition of realism and nominalism developed out of debates over the problem of universals. Universals are terms or properties that can be applied to many things, rather than denoting a single specific individual--for example, red, beauty, five, or dog, as opposed to "Socrates" or "Athens". Realism in this context holds that universals really exist, independently and somehow prior to the world; it is associated with Plato. Conceptualism holds that they exist, but only insofar as they are instantiated in specific things; they do not exist separately. Nominalism holds that universals do not "exist" at all; they are no more than words we use to describe specific objects, they do not name anything. This particular dispute over realism is largely moot in contemporary philosophy, and has been for centuries.

In its modern sense, realism is contrasted with both idealism and materialism, and is considered synonymous with weak dualism. In still a third, and very contemporary sense, realism is contrasted with anti-realism, primarily in the philosophy of science.

Both these disputes are often carried out relative to some specific area: one might, for example, be a realist about physical matter but an anti-realist about ethics. The high necessity of specifying the area in which the claim is made has been increasingly acknowledged in recent years.

Increasingly these last disputes, too, are rejected as misleading, and some philosophers prefer to call the kind of realism espoused there "metaphysical realism," and eschew the whole debate in favour of simple "naturalism" or "natural realism", which is not so much a theory as the position that these debates are ill-conceived if not incoherent, and that there is no more to deciding what is really real than simply taking our words at face value.

Realism in physics
Realism in physics refers to the fact that Bell's theorem proves that every quantum theory must either violate local realism or counterfactual definiteness. Physics up to the 19th century was always implicitly and sometimes explicitly taken to be based on philosophical realism. With the advent of quantum mechanics in the 20th century, it was noted that it is no longer possible to adhere local realism &mdash; that is, to both the principle of locality (that distant objects cannot affect local objects), and a form of ontological realism implicit in classical physics. This has given rise to a contentious debate of the interpretation of quantum mechanics. Although locality and 'realism' are jointly false, it is possible to retain one of them. The majority of working physicists discard 'realism' in favor of locality, since non-locality is held to be contrary to relativity. The implications of this stance are rarely discussed outside of the microscopic domain. See, however, Schrödinger's cat for an illustration of the difficulties presented. It can also be argued that the 'realism' of physics is a much more specific notion than general philosophical realism.

Critics

 * Constructivist epistemology