ABSTRACT
The primary test field for theories of how the world can be known by sight has, over the centuries, been overwhelmingly the general problem of space perception, in particular, distance perception. From the mechanical hypothesis of the 17th century, the interpretation of space as a mathematical concept was a natural consequence of the joint presuppositions that mathematics was true and that nature’s laws were mathematical. In 1709, George Berkeley published An Essay towards a New Theory of Vision. The immediate object of vision is the psychological consequence of the retinal image. In this respect, Berkeley continues the traditions of the eidolon hypothesis and the projective assumption. To develop the contrast between an essential property and an accidental property, consider how one should regard Berkeley’s perceptual quality of faintness as a cue to distance relative to R. Descartes’ and N. Malebranche’s convergence angle as a cue to distance.
