In A Treatise Concerning the Principles of Human Knowledge, Irish philosopher George Berkeley challenges the views of his contemporary John Locke regarding human perception. Written in 1710, this influential work argues that the external world is not made of physical objects, as Locke suggests, but is instead composed solely of ideas. Berkeley asserts that Ideas can only resemble Ideas, meaning our mental concepts are reflections of other ideas rather than material forms. He further posits that this realm of ideas is governed by a divine force—God—who imbues it with structure and order. This thought-provoking treatise invites readers to reconsider the nature of reality and the role of perception in shaping our understanding of the world.