This book contain collection of 6 Books1. An Essay towards a new theory of Vision [1709, 1732]2. A Treatise Concerning the Principles of Human Knowledge [1710]3. Three Dialogues between Hylas and Philonous, in Opposition to Sceptics and Atheists [1713]4. The Analyst: a Discourse addressed to an Infidel Mathematician [1734]5. The Querist [1734]6. A Defence of Free-Thinking in Mathematics [1735]About the AuthorGeorge Berkeley, 1685-1753Philosopher, eldest son of William B., a cadet of the noble family of Berkeley, born at Kilcrin near Kilkenny, and ed. at the school of his native place and at Trinity College, Dublin, where he graduated and took a Fellowship in 1707. His earliest publication was a mathematical one; but the first which brought him into notice was his Essay towards a New Theory of Vision, published in 1709. Though giving rise to much controversy at the time, its conclusions are now accepted as an established part of the theory of optics. There next appeared in 1710 the Treatise concerning the Principles of Human Knowledge, which was followed in 1713 by Dialogues between Hylas and Philonous, in which he propounded his system of philosophy, the leading principle of which is that the world as represented to our senses depends for its existence on being perceived. Of this theory the Principles gives the exposition and the Dialogues the defence. One of his main objects was to combat the prevailing materialism of the time. A theory so novel was, as might be expected, received with widespread ridicule, though his genius was realised by some of the more elect spirits, such as Dr. S. Clarke. Shortly afterwards B. visited England, and was received into the circle of Addison, Pope, and Steele. He then went to the Continent in various capacities, and on his return was made Lecturer in Divinity and Greek in his university, D.D. in 1721, and Dean of Derry in 1724. In 1725 he formed the project of founding a college in Bermuda for training ministers for the colonies, and missionaries to the Indians, in pursuit of which he gave up his deanery with its income of £1100, and went to America on a salary of £100. Disappointed of promised aid from Government he returned, and was appointed Bishop of Cloyne. Soon afterwards he published Alciphron, or The Minute Philosopher, directed against Shaftesbury, and in 1734