BISHOP BERKELEY (1685-1753): George Berkeley was an Anglo-Irish philosopher and clergyman. He was one of the giants of the British Empiricist school of philosophy. He studied divinity and later lectured at Trinity College, Dublin. He went to London to muster support for a venture to establish a college in Bermuda for colonists and Indians in America. Although his college never came to be, he spent three years in the colonies and was a stimulus to the development of higher education in America. In 1734 he was appointed bishop at Cloyne, in which office he devoted himself to the social and economic plight of Ireland. Berkeley is the second of the three great British empiricists, the first being John Locke and the third David Hume. Locke had adopted the view that human knowledge depends on the existence of material objects independent of minds or ideas. These objects causally produce ideas in our minds. Locke held that in some respects our ideas resemble objects in the material world, but some qualities that objects appear to have are not in the objects but depend upon our minds. That is, material objects possess in reality the measurable, quantitative qualities, such as size and weight, but their sense qualities, such as color, odor, and taste, depend upon the mind. Against this view Berkeley argued that objects cannot cause ideas because nothing can resemble an idea but an idea. The argument goes something like this: Is your idea of 'red' red? Is your idea of a football field 100 yards long? Berkeley argued that you could do this little test on all the properties of an object and none of them would be in the idea. Since the idea has no properties in common with the object, then the object could not have caused the idea. Berkely held that all the qualities of the object depend upon the mind. His most characteristic philosophical doctrine is summarized in the Latin expression esse est percipi, "to be is to be perceived." Going beyond the teachings of John Locke, Berkeley's subjective idealism holds that there is no existence of matter independent of perception; the observing mind of God makes possible the continued apparent existence of material objects. In Berkeley's view, therefore, the existence of a divine mind follows directly from the common-sense belief that physical objects exist when no one is perceiving them. This expresses a version of philosophical idealism, the view that nothing can exist apart from minds and the contents of minds. To say that a material object exists, in this view, is to say that it is or can be seen, heard, or otherwise perceived by a mind.