realism (philosophy)

The theory supporting the common-sense view that the world and its contents do not depend for their existence on the fact that some mind (whether human or divine) is aware of them. Plato and others held that universals (eg ‘redness’) or abstract entities (eg numbers) have a real existence outside the mind and apart from their instances. It is opposed to idealism, phenomenalism and nominalism.

The terms Realism or Realist (in reference to an adherent of "Realism"), may refer to...

...in ethnics:

Moral realism, the view in philosophy that there are objective moral values, and a rejection of moral relativism.

...in international relations:

Political realism, a set of theories in international relations that share a common belief that the primary motivation of states is the desire for military and economic power or security, rather than ideals or ethics. Liberal realism, a branch of 'political realism' that maintains that, despite the condition of 'international anarchy', there exists a 'society of states'.

...in law:

Legal realism, a family of theories, developed the early 1900s in the United States and Scandinavia, whose essential tenet is that all law is made by human beings and, thus, is subject to human foibles, frailties and imperfections.

...in philosophy:

Critical realism, a philosophy of perception which posits that while some of our sense-data can and does accurately represent external objects, properties, and events, other sense-data may not be accurate representations. Naïve realism, a common sense theory of perception which it is claimed is representative of most people's understanding and method of interpretation of their perceptions. Platonic realism, is a philosophy which posits the existence of universals, originally described by the Greek philosopher Plato.

...in science:

Scientific realism, a view in the philosophy of science about the nature of scientific success.