George Berkeley
George Berkeley (March 12, 1685 – January 14, 1753) was an Anglo-Irish, Christian, Empiricist philosopher who made insightful advances in metaphysics that influenced both Hume and Kant. His greatest achievement was his theory of idealism which argued the non-existence of matter through a syllogism, making him an immaterialist. Berkeley was born near Kilkenny, Ireland to a noble family. By the time he was 19 he had studied in two universities and earned a bachelor's degree. Three years later, he was made a fellow of Trinity College and was ordained in the Anglican Church. He became the Bishop of Cloyne. Berkeley wrote on philosophy until the end of his life; his studies were rooted in religion and were pointed at contemplating God.
Contributions to Philosophy
Berkeleyan Idealism
Berkeley's treatise against materialism is based in one syllogism:
We perceive ordinary objects. We perceive only ideas. Therefore, Ordinary objects are ideas.[1]
He is stating that physical objects are simply objects of our awareness and not of the external world. He expands on this in great length in A Treatise Concerning the Principles of Human Knowledge which he published in 1710 and uses his Three Dialogues Between Hylas and Philonous, published in 1713, to explain his argument through basic conversation. In the dialogues, Philonous explains the concept to the doubting Hylas through logic. If something is indistinguishable from a pain, then it is a pain. A great degree of heat is indistinguishable from a pain, making them equal. If a pain cannot exist unperceived, no great degree of heat can exist unperceived. If external objects are not the subject of sensations or perceptions, pains and heats cannot exist in external objects. Since pain exists in the mind only, heat must also exist in the mind only.[2] Philonous uses sensations to prove objects are just ideas since sensations are perceived and of the mind alone. The argument can carry over into color and even size as they are both understood and perceived by the mind through our senses. Since matter does not have size or color, it is unknown and unknowable, making it an abstract idea, in Philonous’ feelings, something that is not worth believing in.
In Berkeley's argument, all reality is perceptions, making it all in the mind. Hylas points out that when a person dies, the realm will stop existing. Philonous rebuts this by using it to prove the existence of God. He restates that only minds and their perceptions exist. Since immaterial minds do not fall apart like things made of matter, the immortality of the soul is proven. Berkeley also uses this argument to prove the existence of God because what we perceive is real and real things exist outside of human minds. But since everything exists in the mind, there must be a divine mind that perceives all things.[3]
References
Robinson, Howard. "Berkeley." Ed. E. P. Tsui-James. The Blackwell Companion to Philosophy. Ed. Nicholas Bunnin. 2nd ed. Oxford: Blackwell, 2003. 694-700. Print.
