Combining Texts

Ideas for 'Brainstorms:Essays on Mind and Psychology', 'Regressive Method for Premises in Mathematics' and 'Vagueness and Contradiction'

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2 ideas

12. Knowledge Sources / B. Perception / 2. Qualities in Perception / d. Secondary qualities
The colour bands of the spectrum arise from our biology; they do not exist in the physics [Sorensen]
     Full Idea: The bands of colour in a colour spectrum do not correspond to objective discontinuities in light wavelengths. These apparently external bands arise from our biology rather than simple physics.
     From: Roy Sorensen (Vagueness and Contradiction [2001], Intro)
     A reaction: If any more arguments are needed to endorse the fact that some qualities are clearly secondary (and, to my amazement, such arguments seem to be very much needed), I would take this to be one of the final conclusive pieces of evidence.
12. Knowledge Sources / B. Perception / 5. Interpretation
We are unable to perceive a nose (on the back of a mask) as concave [Sorensen]
     Full Idea: The human perceptual system appears unable to represent a nose as concave rather than convex. If you look at the concave side of a mask, you see the features as convex.
     From: Roy Sorensen (Vagueness and Contradiction [2001], 4.3)
     A reaction: I don't think that is quite true. You wouldn't put a mask on if you thought it was convex. It is usually when seen at a distance with strong cross-lighting that the effect emerges. Nevertheless, it is an important point.