In metaphysics, the view that stresses the central role of the ideal or the spiritual in the constitution of the world and in mankind's interpretation of experience. Idealism may hold that the world or reality exists essentially as spirit or consciousness, that abstractions and laws are more fundamental in reality than sensory things, or, at least, that whatever exists is known to mankind in dimensions that are chiefly mentalthat is, through and as ideas. Metaphysical idealism asserts the ideality of reality; epistemological idealism holds that in the knowledge process the mind can grasp only its own contents. Metaphysical idealism is thus directly opposed to materialism, and epistemological idealism is opposed to realism. Absolute idealism (seeG. W. F. Hegel) includes the following principles: (1) the everyday world of things and persons is not the world as it really is but merely as it appears in terms of uncriticized categories; (2) the best reflection of the world is in terms of a self-conscious mind; (3) thought is the relation of each particular experience with the infinite whole of which it is an expression; and (4) truth consists in relationships of coherence between thoughts, rather than in a correspondence between thoughts and external realities (seecoherentism). See alsoGeorge Berkeley.