antirealists

Antirealists are philosophers who challenge the claim that realism about certain domains, most notably the unobservable aspects of scientific theories, correctly describes how the world is. They question whether our best scientific theories must reveal mind-independent truth about unobservables and instead emphasize other aims such as predictivity, empirical adequacy, or usefulness.

In the philosophy of science, antirealism contrasts with scientific realism. The principal forms are instrumentalism, which treats theories as tools for organizing experience and predicting phenomena without asserting the real existence of unobservables; and constructive empiricism, advanced by Bas van Fraassen, which maintains science aims to be empirically adequate rather than true about unobservable entities. Other strands maintain that successful theories do not justify claims about a deeper, mind-independent reality, or that our theoretical concepts are underdetermined by evidence.

Antirealism can also appear in other areas of philosophy, including ethics and the philosophy of mathematics. In ethics, moral anti-realists deny objective moral facts and instead appeal to non-cognitive or non-truth-apt criteria for evaluating statements. In mathematics, anti-realist positions such as nominalism or fictionalism deny the independent existence of mathematical objects, instead treating mathematical discourse as about non-mexistent or fictional entities or as a formal game with rules.

Key debates center on whether the success of science requires reference to an unseen reality or can be explained without ontological commitment to unobservables. Critics of anti-realism argue that realism provides a best explanation of predictive success and the stability of scientific concepts across theory change. Notable proponents of anti-realism include Bas van Fraassen and various defenders of instrumental or empirical approaches.