By George Berkeley.
Three Dialogues between Hylas and Philonous, in opposition to Sceptics and Atheists is available here, in both an HTML version, and also in various printable formats.
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This text is based on the edition of the Three Dialogues between Hylas and Philonous published with the Treatise concerning the Principles of Human Knowledge by Jacob Tonson in 1734, and (with a small number of exceptions) follows the spelling, capitalization and punctuation of the original.