The Idealism of George Berkeley 

In this video, Professor Thorsby discusses the major arguments of George Berkeley. We see that Berkeley begins by denying the possibility of abstract ideas, at least in terms of their significance defined by John Locke. He contends that Locke makes a mistake by confusing the notion of abstract ideas with the limits of language. Our perception of an object is not generated through an accumulation of simple ideas, amalgamated in a abstract whole (all with valid representational content), but through the direct complete ideas themselves. Berkeley goes on to show that existence requires perception such that all things that exist must be perceived. The lecture traces some of the consequences that follow.