Path: utzoo!attcan!uunet!cs.utexas.edu!yale!cs.yale.edu!mcdermott-drew From: mcdermott-drew@cs.yale.edu (Drew McDermott) Newsgroups: comp.ai.philosophy Subject: Re: Definition of (was Re: Testing for []) consciousness Summary: What is like to be Nagel? Message-ID: <26910@cs.yale.edu> Date: 24 Oct 90 17:18:37 GMT References: <27608@usc.edu> <1990Oct22.150143.13858@canon.co.uk> Sender: news@cs.yale.edu Organization: Yale University Computer Science Dept., New Haven, CT 06520-2158 Lines: 51 Nntp-Posting-Host: aden.ai.cs.yale.edu Originator: dvm@aden.CS.Yale.Edu I'd like to respond to this proposal by rjf@canon.co.uk (Robin Faichney): I'd like to suggest that something be ascribed consciousness iff it can be the subject of experience: iff it is like something to be that thing. (This is lifted from T Nagel, actual references not to hand but available on request.) If you think it is like something to be a bat, that the bat experiences anything, then you think the bat conscious; if not, then not. If you think it is like something to be a house brick, that the brick experiences anything, then you think the brick conscious. If you think it like something to be a PC, then you think the PC conscious. I don't think Nagel's proposal does much toward defining what it means to be conscious (or even what it means to ascribe consciousness to something). The problem is the word "like." If we take it literally, meaning "similar to," then we are asking questions of this form: "Is being a bat similar to something?" Suppose I strap on wings and carry a portable sonar. Would being a bat be similar to that? Now suppose I lie quietly for hours and hours. Would being a brick be similar to that? Presumably I am missing the point. Presumably saying that it is "like something to be a bat" and that it is not "like anything to be a brick" is just a roundabout way of saying bats are conscious (assuming they are) and bricks are not. Where does this get us? Fortunately, we don't have to define consciousness. We only have to come up with a theory of how it works. This is (supposed to be) an account of the ordinary concept of consciousness, which is why I think it the one for AI. Even though it is entirely subjective. That's just AI's tough luck! ;-) (Or good luck?) Formulating a more objective definition is just trying to move the goal posts. Actually, I think some AI people are resistant to this definition not because it upsets their professional picture, but because it upsets their personal picture -- as it does those of most of us. It is so radical that it takes a long time to sink in. (You mean there really is something which is *completely* subjective??) Though perhaps longer for some than for others! ;-) Manifesto: Nothing is entirely subjective. Show me an unobservable something and I'll show you a nothing. -- Drew McDermott