grand illusion argument

   The term grand illusion argument refers to a form of philosophical scepticism that questions the nature of our perceptual experience. It is distinguished from the classical scepticism of philosophers such as Pyrrho of Elis (c. 360-c. 270 Bc) and Sextus Empiricus (c. AD 160-210), which challenges our belief in the existence of the world as such. Proponents of the grand illusion argument or 'new scepticism' hold that our beliefs about the nature of our perceptual experience are fundamentally wrong, in the sense that we believe it to be rich, detailed, continuous, and more or less complete, whereas empirical studies demonstrate that it is limited, discontinuous, non-uniform, and fragmented. The grand illusion argument was developed on the basis oflate-20th-century work in psychology and philosophy of mind on phenomena such as * change blindness, *inattentional blindness, *repetition blindness, *inattentional deafness, *auditory deafness, *tactile insensitivity, and the 'filling in' of the *blind spot. Pathophysiologically, the mediation of grapheme-colour synaesthesias is associated primarily with * cross-activation between regions of the parietal lobe involved in numerical cognition and spatial cognition. For other pathophysiological hypotheses, see the entry Synaesthesia.

   References

   Groarke, L. (1990). Greek scepticism. Anti-realist trends in ancient thought. Montreal: McGill-Queen's University Press.

   Noë, A., ed. (2002). Is the visual world a grand illusion? Thorverton: Imprint Academic.