An Essay Towards a New Theory of Vision

George Berkeley's An Essay Towards a New Theory of Vision (1709) explores visual perception, specifically distance, size, and position. Berkeley argued that the perceived objects of sight are not external to the mind, unlike tangible objects. This work laid groundwork for his broader philosophical system, presented in A Treatise Concerning the Principles of Human Knowledge (1710), where he posited that reality consists solely of minds and their ideas. For Berkeley, physical objects exist only insofar as they are perceived, a concept summarized by the Latin phrase esse est percipi ("to be is to be perceived"). This idealist philosophy challenges the notion of an independent material world, suggesting that what we perceive are essentially collections of sensory ideas within a mind.12