George Berkeley was an Anglican bishop and philosopher. He tried to reconcile the science of his day with Christianity.

Berkeley argued that physical things, such as tables and trees, consist entirely of the ideas or sensations we have of them. In his view, an apple is nothing but its color, shape, texture, weight, taste, and other qualities, all of which we experience through our senses. He argued that the qualities or ideas that we experience exist only in our minds. They change as the person perceiving them changes. For example, the same lukewarm water seems warm to a cold hand and cool to a warm hand. Thus, it seemed to Berkeley, the qualities we perceive are really ideas that depend upon the mind perceiving them and have no independent existence.

Other philosophers had believed that a physical thing also consists of matter. Matter is the stuff in which the various qualities are supposed to exist. Matter supposedly exists outside of and independent of the mind. But because we never have any direct experience of matter, Berkeley claimed that we have no good reason to think it exists.

If, as Berkeley argued, the entire physical world consists only of ideas, then the world exists only in the minds that perceive it. However, because we believe that physical things continue to exist when we are not observing them, we must assume that there exists a mind that observes all physical things all the time. It is only the constant observation by such a mind that keeps things in existence when we are not observing them. This universally present and observant mind is God.

Because Berkeley believed that things are entirely composed of ideas, he is a representative of philosophical idealism. Because his view of the world is restricted to what we learn in our direct experience of it, he also represents philosophical empiricism. Berkeley was born in County Kilkenny, Ireland.

Ivan Soll, Ph.D., Prof. of Philosophy, Univ. of Wisconsin, Madison.

SOURCE: IBM 1999 WORLD BOOK