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Clarifying `Consciousness'

Note that Proposition 1' marks a shift from talk of cognition to talk of consciousness. `Consciousness' is a narrower term than `cognition.' Cognition, that is, includes consciousness.gif It follows that if consciousness isn't reversible, then the broader phenomenon of cognition isn't either. (Of course, many elements of cognition are computable.)

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Figure 2: Schacter's Model

It's important to realize that we have something rather specific in mind when we use the term `consciousness' in this paper: we have in mind what is sometimes called phenomenal consciousness. Ned Block [8], in a recent essay on consciousness in Behavioral and Brain Sciences, calls this brand of consciousness P-consciousness. Here's part of his explication of this concept:

So how should we point to P-consciousness? Well, one way is via rough synonyms. As I said, P-consciousness is experience. P-conscious properties are experiential properties. P-conscious states are experiential states, that is, a state is P-conscious if it has experiential properties. The totality of the experiential properties of a state are ``what it is like" to have it. Moving from synonyms to examples, we have P-conscious states when we see, hear, smell, taste and have pains. P-conscious properties include the experiential properties of sensations, feelings and perceptions, but I would also include thoughts, wants and emotions. ([8], p. 230)

Block distinguishes between P-consciousness and A-consciousness; the latter concept is characterized as follows:

A state is access-conscious (A-conscious) if, in virtue of one's having the state, a representation of its content is (1) inferentially promiscuous, i.e., poised to be used as a premise in reasoning, and (2) poised for [rational] control of action and (3) poised for rational control of speech. ([8], p. 231)

Note that it's plausible to regard certain computational artifacts to be bearers of A-consciousness (e.g., theorem provers with natural language generation capability), whereas we shall now attempt to establish that P-consciousness (hereafter referred to by simply `consciousness') is beyond computation:


next up previous
Next: The Argument From Irreversibility Up: The Argument From Irreversibility Previous: The Starting Point: Proposition

Selmer Bringsjord
Fri Sep 6 11:58:56 EDT 1996