Whether viewed as extreme scepticism or enlightened common sense, the writings of Berkeley are a major influence on modern philosophy. Bishop Berkeley (1685-1753) was one of the great British empirical philosophers. He believed that the existence of material objects depends on their being perceived and The Principles of Human Knowledge sets out this denial of non-mental material reality. At first his views were unfavourably received by the London intelligentsia, and the entertaining Three Dialogues between Hylas and Philonous are a clarification of the Realist argument and a response to accusations of atheism and scepticism. In the nineteenth century John Stuart Mill wrote that he considered Berkeley's work to be of 'greatest philosophic genius', and it is true to say that its Immaterialism has influenced many recent philosophers.