Realism is the doctrine that existence is separate from conceptions of it. People may think and talk of different entities, but the entities themselves have a reality that is logically independent of thought and language. This may seem a matter of common sense; surely chairs and tables do not exist only in so far as one thinks of them, or perhaps perceives them. People do not conjure things into existence through their minds, in the way that dreams create a world that vanishes when one wakes up. Yet to appeal to common sense is to appeal to the philosophical views of previous generations that have gained common currency. The position itself needs some philosophical justification. Dr. Samuel Johnson is supposed to have dealt with Bishop George Berkeley's idealism by simply kicking a stone and exclaiming "I refute it thus!": This is hardly an argument.

Contention with idealism

Realism is in fact most often opposed to idealism. The latter claims that all reality is a construction out of mental processes. As Berkeley (1685–1753) said in his Treatise Concerning the Principles of Human Knowledge, "To be is to be perceived." In other words, what exists does so because it is perceived, and is not perceived because it exists. The latter would be the realist position. Yet Berkeley's position not only makes all reality mental, it also restricts what can exist to what is within the range of someone perceiving it. Berkeley met this by appealing to the omniscience of God, so that everything is perceived by God, and therefore exists. The danger is that God is removed from the picture; this is a move empiricism tends to encourage. The view then becomes one that ties reality to actual or possible human experience. This, in turn, makes reality anthropocentric. What humans cannot perceive cannot exist. Since contemporary physics wishes to deal with subatomic particles and other unobservable entities, such as, say, the interior of a black hole, this does not seem to give an adequate account of the assumptions of present-day science.

Although realism may be classically opposed to idealist tying of existence to mind, realism comes in many shapes and sizes. It can be a global, metaphysical doctrine, or it can be limited to particular areas of human activity. One could be a realist about the objects of scientific investigation, but not about the concerns of morality. The main point of realism, though, is always to pull apart the fact of existence from issues concerning how anyone can know what exists. Ontology and epistemology should not be confused. (So-called critical realism tends to link the two). The metaphysical realist will stress the objectivity of the "world" or whatever exists. It cannot depend in any way on the way people think about it or discover it. Even scientific realism may seem realist in its insistence on the independent reality of the objects of science. It can, however, become antirealist when it asserts that only the objects of science can exist. In other words, existence is then restricted to what lies within the scope of actual or conceivable science. Because that must be human science, reality is being artificially restricted to what is within the scope of human capabilities to discover.

Ontological bases of science and religion

The focus of realism must always be reality, and not issues of how one can come to know reality. Otherwise questions about existence become changed into questions about human abilities. What lies beyond human abilities cannot even be conceived to exist. A major motive for scientific research is the knowledge of human ignorance. The world is not limited to present knowledge, nor to what people are able to discover. This becomes of crucial importance in the field of religion, which is normally understood as attempting to talk of what is transcendent, or ontologically separate, from the world with which people are normally familiar. Empiricist philosophy from the time of David Hume (1711–1776) has attempted to restrict language to what is within human experience. This is always to change the subject from reality to human knowledge. Yet realism cannot rest content with metaphysical assertions about the status of reality. A reality to which people are oblivious is no better than nothing at all. Ontology needs epistemology: It is just not identical to it.

Both science and religion need a strong realist underpinning. They must be about something. Science has to assume that it is investigating a world that has an independent existence. Otherwise it is a mere social construction reflecting the conditions of particular societies at a particular time. Similarly, any religion must assume that it is concerned with a reality that is not the creation of human imagination. Theism must have a realist outlook. It is making claims about an objective reality that are contradicted by atheism, itself also a realist view. Indeed, if God or other spiritual realities are mere projections of human thought or language, religion is guilty of a massive bout of wishful thinking. If the realities described do not actually exist, there is no ground for any cosmic optimism. The antirealist may complain that this is already assuming a realist interpretation of religion. Yet, the idea that neither religion nor science engage with anything beyond themselves seems to negate their most important function of claiming truth. If they are conceived of as conceptual schemes, practices, or forms of life, with no external justification, there seems no point in taking part in them. There can be no justification or reason for being religious, or doing science.

According to realist understanding, however, there is an independent world for both science and religion to relate to. Moreover, each purports in various ways to describe parts of the same objective world. This in itself provides sufficient ground for trying to show connections between the two. Whatever their distinctive methods, one can not rule out either the possibility of conflict or of mutual support. For example, if this is God's world, this might give an explanation for the inherent order and regularity, which science needs to assume, in order to generalise from particular findings.

See also CRITICAL REALISM

ROGER TRIGG