The colors and shapes of visual experiences
When we see a tomato in standard circumstances, we see something red and round. According to common sense, the red, round thing we see is the tomato itself. When we have a hallucinatory vision of a tomato, however, there may be present to us no red and round physical object. Still, we use the words "red" and "round" to describe that situation as well, this time applying them to the visual experience itself. We say that we have a red, round visual image, or a visual experience of a red disk, or some such. Because we see physical objects far more often than we hallucinate, we apply terms for color and shape to physical objects far more often than to visual experiences. Moreover, different theories of perception explain in different ways the applications such terms have to physical objects and to visual experiences. But whatever their frequency and explanation, it seems clear that both sorts of application occur.
Rosenthal, D. (1999)., The colors and shapes of visual experiences, in D. Fisette (ed.), Consciousness and intentionality, Dordrecht, Springer, pp. 95-118.
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