From: SMTP%"phayes@cs.uiuc.edu" 6-MAR-1996 15:16:57.91 To: STAPP CC: Subj: Re: Reply to Hayes 4 Message-Id: <199603062314.RAA01047@tubman.ai.uiuc.edu> X-Sender: phayes@tubman.cs.uiuc.edu Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Wed, 6 Mar 1996 17:18:31 -0600 To: STAPP@theorm.lbl.gov From: phayes@cs.uiuc.edu (Pat Hayes) Subject: Re: Reply to Hayes 4 Henry, your name got left out, sorry!! Pat ------------ >X-Sender: phayes@tubman.cs.uiuc.edu >Date: Tue, 5 Mar 1996 19:01:02 -0600 >To: "Gregg Rosenberg" >From: phayes@cs.uiuc.edu (Pat Hayes) >Subject: Re: Reply to Hayes 4 >Cc: klein@adage.berkeley.edu, phayes@cs.uiuc.edu, A.Sloman@cs.bham.ac.uk, > keith@imprint.co.uk, mckee@neosoft.com, brings@rpi.edu, > patrickw@cs.monash.edu.au > >... >If Greggs account of Henrys position is right, then indeed I have been >badly misunderstanding him. I more or less agree with >Stapp-according-to-Rosenberg. We must leave the decision to Henry, I guess. > > >Are indeed we all agreed that P=F ? Henry has been most insistent that this >is false, but if what he meant was that it is true, then maybe we should >try to come to terms on a more useful common vocabulary. > >This entire argument has had nothing to do with AI, or whether knowing F >enables one to infer all of P. > >> >>That said, Henry has also just produced the correct answer to Pat's challenge >>concering the identity F=P. I found his presentation a little >>confusing, though, so I am anticipating Pat might too. To try and head off a >>further round of talk, I'm going to try to make the point Henry just made >>in slightly different language. >> >>Everyone seems agreed that one can know P without knowing it is F. > >My understanding of Henrys position is precisely the opposite: that the >fact that one can know P in a special way, but not know F that way, entails >that P is NOT the same as F. (No corner-quotes here, notice: this means >knowing an entity, not a proposition.) > >For >>instance, as a child does. Similarly, everyone I think is agreed that >>one can know F without knowing the facts about P. As, for example, it >>seems that I do (unlike Pat, all my work in AI never gave me the magic >>insight into how it explained everything I knew about P). > >Ive never even THOUGHT such a claim, let alone expressed it. (If AI >succeeded, we'd have an artifical mind, To discover what it *felt* like *to >it*, you'd have to ask it, not me.) > >So, then, there >>is a prima facie problem: If F=P, how can one come to know about one >>but not know about the other? This is a classic problem in phil (at least >>since Frege), and has a standard solution. The solution is that F and >>P are presentations of the same thing under different aspects. In the evening >>star and morning star example, both MS and ES are presentations of Venus, but >>in different relations to observers on earth. > >I think you mean, and

are presentations.(where these are >cornerquotes) F and P are experiences and neural events. > >>Now, the question is this: given two prima facie different aspects, what >>conditions must be met if they are to be aspects of the same object? >> >>The answer is this: Once one has all the facts about that object, the >>facts about *both* aspects must be entailed by that complete set. > >No: that is a consequence of the actual identity condition, which is simply >that there is one object to which

and both refer. > >All this talk of 'aspects' and entailment seems to be quite off on a >tangent. (I suspect, an epistemological tangent concerning how we could >*know* that an identity were true??) > >For >>instance, once one has all the facts about Venus, the fact that >>Venus = Morning Star and that Venus = Evening Star is entailed. >>Venus satisfies the prior identification conditions of both MS and >>ES. By transitivity of identity, MS=ES. >> >>In this debate it is important, especially for Pat, to realize most >>sides *agree* that P and F are different aspects of the same thing. The >>disagreement is whether or not both aspects are physical. So Pat is making >>a stronger claim. He claims that they are both *physical* aspects of >>the brain, and, further, that F is the same aspect as P (i.e., F=P). > >Not at all! I never said anything about 'aspects', or claimed that the >language of P had to be physical. To say that P = F is not to say that

>= (imagine the quoted symbols replaced by the appropriate >descriptions.) > >>What would make Pat's claim true? How could it be tested? > >WAAAIIITTT a minute here! This has been happening to me a lot lately in >these arguments!! Im NOT claiming that P=F or any other damn thing about >mental life. All I was doing was suggesting that SUCH A CLAIM IS COHERENT; >that at last it cannot be ruled out. Henry argued that it was impossible, >and I suggested a flaw in his reasoning. > >>........ The interesting and worthwhile project is justifying >>the identity without assuming it. > >The identity might be part of a theory which makes testable predictions. To >hypothesise an identity is a perfectly reasonable way to conduct science: >light IS electromagnetic radiation (A philosopher can be heard muttering, >'but you can't *see* magnetism, so there must be a category error...') > >> >>It is pretty trivial that the physical facts about the brain will entail the >>facts about F, its functioning. Unfortunately, as Henry and many others have >>pointed out, the physical facts don't entail the facts about P. > >This claim is entirely moot. Nothing like this has been 'shown'to be true >by anyone. Such a demonstration would have to rule out, a priori, entire >fields of investigation that have not yet even been thought of. > >If it comes to a bet between the creativity of scientists and the >imaginative limitations of philosophers like Ned Block, I'm with the >scientists every time. > >..... > >Pat > > >---------------------------------------------------------------------- >Beckman Institute (217)244 1616 office >University of Illinois (217)328 3947 or (415)855 9043 home >405 North Mathews Avenue (217)244 8371 fax > >Urbana, IL. 61801 Phayes@ai.uiuc.edu >---------------------------------------------------------------------- > > ---------------------------------------------------------------------- Beckman Institute (217)244 1616 office University of Illinois (217)328 3947 or (415)855 9043 home 405 North Mathews Avenue (217)244 8371 fax Urbana, IL. 61801 Phayes@ai.uiuc.edu ----------------------------------------------------------------------