Knowledge in perception and illusion.
R L Gregory
Philosophical transactions of the Royal Society of London. Series B, Biological sciences August 1, 1997 DOI: 10.1098/rstb.1997.0095 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Theoretical or philosophical paper Peer reviewed |
|---|---|
| Keywords | Humans Cognition Consciousness Optical illusions Visual perception |
| Key points | Argues that visual perception works like unconscious inference from sensory data and past knowledge, akin to scientific predictive hypotheses but projected outward and taken as immediate reality. Proposes a tentative classification of visual illusions by appearances and kinds of causes, and suggests real-time sensory input, perhaps flagged by qualia of consciousness, signals the present and prevents confusion with the past. |
Abstract
Following Hermann von Helmholtz, who described visual perceptions as unconscious inferences from sensory data and knowledge derived from the past, perceptions are regarded as similar to predictive hypotheses of science, but are psychologically projected into external space and accepted as our most immediate reality. There are increasing discrepancies between perceptions and conceptions with science's advances, which makes it hard to define 'illusion'. Visual illusions can provide evidence of object knowledge and working rules for vision, but only when the phenomena are explained and classified. A tentative classification is presented, in terms of appearances and kinds of causes. The large contribution of knowledge from the past for vision raises the issue: how do we recognize the present, without confusion from the past. This danger is generally avoided as the present is signalled by real-time sensory inputs-perhaps flagged by qualia of consciousness.
Citations in the library
Cited by 15
- Finding out about filling-in: a guide to perceptual completion for visual science and the philosophy of perception. Behavioral and Brain Sciences December 1, 1998
- Top-down influences on ambiguous perception: the role of stable and transient states of the observer Frontiers in Human Neuroscience December 8, 2014
- Brain Networks, Neurotransmitters and Psychedelics: Towards a Neurochemistry of Self-Awareness. Current Neurology and Neuroscience Reports August 1, 2024
- The Confluence of Perceiving and Thinking in Consciousness Phenomenology. Frontiers in Psychology 2017
- Embodying Metaverse as artificial life: At the intersection of media and 4E cognition theories Filozofija i Društvo 2022
and 10 more in the library