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You know a funny thing about the contemporary
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neuroscience of consciousness is it's really closet philosophy. It's really it's
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very often making fundamental philosophical assumptions. That is to say it\\'92s taking
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certain philosophical ideas for granted and it\\'92s often using empirical information
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simply to reanimate old debates. For example, one of the basic sort of guiding pictures
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I think that people thinking about the neuroscience of consciousness have is that the world is
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in our head The brain makes the world, that is what we experience is not\\'97I don\\'92t
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experience you. I don\\'92t see you. I experience something in my brain that is confabulated
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on the basis of a pattern of stimulation.\\ Let me come to the nature of color as an example
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to try to illustrate what I have in mind. And by the way this is a wonderful area where
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both science and philosophy have tended to really collaborate, have been in dialogue
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with each other and in many cases the leading philosophers have also been the leading scientists
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thinking about this. One view is that color is a property of the surfaces of objects,
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not the property we naively think we see, but maybe something like a disposition to
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absorb and reflect light of certain wavelengths and to produce a sort of what is known as
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a spectral reflectance profile, but the color is on the surface. Another view is that it\\'92s
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an illusion to think of color as something in the thing, that color is merely an affect
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that the thing has on us. In that sense the color happens to us. The leaves in the tree
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are not green. Greenness is just something that happens. In me it\\'92s a kind of sensation
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that is produced thanks to the activation of my nervous system by those leaves.\\
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My own view is that both of those views are wrong. I advocate the view that color is what
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you might call an ecological property and by that I mean color is a feature of the way
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light and surfaces interact. It\\'92s not in that sense intrinsic to the surface of the
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leaf that it is green. Its greenness is the way it behaves in relation to lighting. So
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we think of the color as stable, but of course the color looks one way under one light and
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if you take it outside it looks different and if you turn it in certain ways there will
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be highlights and sort of little specular shining points on the surfaces of things that
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are all part of the real color of the thing. For me colors are like shapes. Just as a three-dimensional
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shape has a hidden backside so colors have hidden ways they would look if the conditions
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of lighting were changed.\\ The problem of skepticism about the external
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world, how do we know that things are the way they seem to be, how do we know that our
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perceptual experiences are reliable is a chestnut. It\\'92s an old philosophical chestnut that
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I can\\'92t solve for you right now and that neuroscience can\\'92t solve, but what I\\'92d
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like to impress on you is that neuroscience has taken a solution to that or at least an
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attitude towards that old philosophical chestnut for granted and most neuroscientists working
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on consciousness suppose experience is something that happens inside of me. It\\'92s subjective.
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It\\'92s hidden. The world is this we know not what which is beyond the surfaces of our
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tent. Beyond the reach of our direct knowledge because all we ever know is the way our nervous
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system is bombarded by stimulation, that which is causing the stimulation is always beyond
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Directed / Produced byJonathan Fowler
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& Elizabeth Rodd
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}