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Access and Phenomenal Consciousness. Joe Lau Philosophy HKU. Readings. Pinker’s article on reserve Ned Block’s papers “On a Confusion …” “How not to …” http://www.nyu.edu/gsas/dept/philo/faculty/block/ Other references : The introduction in Davies & Humphrey (eds.) Consciousness .
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Access and Phenomenal Consciousness Joe Lau Philosophy HKU
Readings • Pinker’s article on reserve • Ned Block’s papers • “On a Confusion …” “How not to …” • http://www.nyu.edu/gsas/dept/philo/faculty/block/ • Other references : • The introduction in Davies & Humphrey (eds.) Consciousness. • The Nature of Consciousness edited by Block and others.
Phenomenal and Access • X is P-conscious = there is something it is like to have X. • X is A-conscious = The information contained in X is “poised” (directly available) for reasoning, reporting or rational control of action.
Examples • P : • Sensations : pains, itches, taste, … • Visual imagination • A : • Conscious thoughts and reasoning • Perhaps these are cases with both A and P?
What about pain? • Pain is presumably P-conscious. • But is it A-conscious? A-conscious states must be information-bearing states. • Perhaps we should take pain as an information state. • Information about location and extent of bodily injury.
Phantom limbs • Many amputees still feel pain in their limbs after amputations. • Explanation : they still have pain states that represent damage in a non-existing limb.
Correlation and identity • A and P seem to be closely correlated. • Maybe they are the same thing? • Two different concepts can pick out the same thing. • Would be nice if P can be reduced to A.
Explanatory problem • Difficult to see how P can be explained. • Suppose : • “P = computational / neural state X.” • But : • “Why should having X feel like something?”
A-consciousness not problematic • A-consciousness can probably be explained computationally. Reasoning RationalAction Control A-conscious Mental State LinguisticReport Memory
Against correlation • No correlation, no identity. • To show that P is not A, we need to find cases of : • A without P, or • P without A
A without P? • Purported examples • AI Computers • Sleep-walking • Zombies • But how do we know that there is no P?
Better example • Hartmann, J.A. et.al. (1991), “Denial of visual perception” Brain and Cognition16, 29-40 • Patient at chance at telling whether a room is illuminated or dark. • Small preserved island of V1. • Can read single words and recognize faces when presented to the upper right part of the visual field. • When asked how he knows the word or the face, he says “it clicks” and denies seeing the stimuli.
Comments • How do we know he is not lying? • Or self-deception? • Is this possible? • A creature might have a P-conscious mental state X without being able to report that X is P-conscious, even though the information in X is available. • Maybe A is necessary but not sufficient for P?
P without A? • Experience of background noise : • P-conscious but not available? • Aerodontalgia • Toothache brought on by reduction of atmospheric pressure. • There are also cases of post-operation reports of pain under general anesthesia.
Comment • But these examples do not seem too convincing : • Information can be poised for reasoning, reporting and action even if the systems for reasoning and reporting are inactive or too busy to access the information.