Representation of reality in the perceptual world

What contribution can neurobiologists make to the philosophical issues involved in the Theory of Knowledge? The sensory physiologist or psychologist must start with the assumption (albeit philosophically naive) that the biological function of sense organs is to act as transducers of genuine events in the outside world, and thus to contribute to an internal description of external reality. Although visual perception seems to its introspecting owner to be a unitary process, involving an integrated and complete description of all the properties of the visual scene, there is now good evidence that sensory processing of messages from the eyes involves a great deal of filtering of information and anatomically segregated analysis of such features as shape, colour, movement and distance. Sensory neurobiology can say little about the way in which conscious perceptions are synthesized from the heap of features into which the sensory signals are shattered, about how the inherent ambiguity of messages from sensory neurons is overcome, or about how the ultimate percepts are externalized. Finally, the evidence that the nature of the sensory world varies from species to species forces us to re-examine the theory of solipsism in biological terms.