Epipenominal Qualia 1 - The knowledge Argument

["David Saitch" <philosophy@saitch.net>]

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I am splitting this into two sections for the sake of size.

This section looks at Jackson's Knowledge argument, the next will address his
Epiphenominal justification.

Frank Jackson?s aim in the paper ?Epiphenomenal Qualia? is to try to prove
that phenomenal qualities, or qualia, are mental events, which are
non-physical and have no causal properties, thus refuting Physicalism.

The central argument in Jackson?s paper is based around his thought experiment
concerning a scientist called Mary, caught in a very odd situation.  

She is the most brilliant neuroscientist there has ever been, who has locked
in a room in which everything is black and white all her life, and she has
never seen any other colours. However, during her dull, grey existence,
perhaps driven by the sad lack of colour, she has done so much research that
she understands everything there is to know about vision and colour
perception. She knows far more than any current neuroscientist; there is
nothing to be known about colour perception that Mary does not know.

Then, one day, she is released from the room and her first sight is a red rose
if full bloom.

Jackson argues that her sight of red will give her something she didn?t have
before, the conscious experience of red. But, he says, since she knew all of
the physical facts about colour perception prior to her release, this
experience must be non-physical.  Physicalism is, therefore, false.


P1 If Physicalism is true then all knowledge is entailed from physical facts 

P2 Prior to release, Mary knows all the relevant physical facts about vision

P3 Prior to release Mary has seen no colours other than black and white

P4 On release Mary learns what it is like to see all colours

P5 If Mary has learned something new based on P2 it must be non-physical

Therefore:

C Physicalism is false 


Most of the Physicalist responses to this are targeted at P4/5, quaestioning
what she has learned:

Dennett - Nothing
Lewis - The ability to use colours
Papineau - Conceptual dualism, ontological monism

I, however will attack premise P2.

I believe Jackson is using our unavoidable Dualism Intuition to smuggle in an
unseen limit on knowledge he says Mary has. The natural view is to think of
the manner in which light of various wavelengths hit the retina and excite the
cone cells, how the cone cells are specialised to pick up short, medium or
long waver light, the manner in which nerve fibres transmit signals to the
visual cortex in the occipital lobe and so on.  But does that sum up all the
physical knowledge? 

As a Physicalist I believe that when I see red and experience it, that is a
physical event. 

This means that from a Physicalist point of view the seeing and experiencing
of red MUST be included in any subset of facts that is supposed to include all
the physical facts about seeing red.

In fact, thinking further, I am tempted to claim that seeing and experiencing
red are the ONLY physical facts - the facts about retina, nerves de dah de dah
are explanations about the physical facts.

So Mary could not have ALL the physical facts about colour perception without
seeing the colour and the argument is killed.





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