The Works of George Berkeley. Vol. 1 of 4: Philosophical Works, 1705-21

George Berkeley made the most radical claim in Western philosophy: matter does not exist. Everything we call a "physical object" is simply a collection of ideas in a mind, and to be is to be perceived. This volume presents the foundational works of the 18th century's most daring empiricist, the philosopher who argued that the chair you're sitting in, the ground beneath your feet, and indeed your own body are nothing but ideas sustained by divine perception. Here are the Three Dialogues between Hylas and Philonous, where Berkeley demolished materialism through Socratic conversation; the Principles of Human Knowledge, his systematic assault on abstract ideas and matter; and the Essay towards a New Theory of Vision, which transformed how we understand perception itself. These early works established the idealist framework that would influence everything from German idealism to contemporary philosophy of mind. For anyone who has ever wondered whether the external world truly exists independent of observation, Berkeley offers a mind-bending answer that remains electrifyingly controversial three centuries later.