From: SMTP%"phayes@cs.uiuc.edu" 7-MAR-1996 10:20:09.54 To: STAPP CC: Subj: Re: Reply to Hayes 4 Message-Id: <199603071810.MAA03371@tubman.ai.uiuc.edu> X-Sender: phayes@tubman.cs.uiuc.edu Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Thu, 7 Mar 1996 12:11:31 -0600 To: klein@adage.Berkeley.EDU (Stanley Klein) From: phayes@cs.uiuc.edu (Pat Hayes) Subject: Re: Reply to Hayes 4 Cc: ghrosenb@phil.indiana.edu, phayes@cs.uiuc.edu, A.Sloman@cs.bham.ac.uk, STAPP@theorm.lbl.gov, brings@rpi.edu, keith@imprint.co.uk, mckee@neosoft.com, patrickw@cs.monash.edu.au Stan- >After sending out my last message I looked over several of the other >messages that flew by today. Some clarity seems to be brewing. Let me see >if I am catching on. Pat seems to be claiming that the area 12 activity "is" >the pain. Others (like me) are claiming that the area 12 activity "is >necessary and sufficient for" the pain. I think that sums it up well. (Just to be overly formal for a second, it deosnt actaully make sense to say that a THING is necc & suff: you have to say that the *existence of the area 12 activity* is necessary , etc.) >I would never be brave enough to say >that the activity is the pain since they seem so different. This is worth enlarging upon. First, its the *descriptions* that seem to be different; but of course it often happens that one thing can be accurately described in very differen ways, so theres nothing puzzling there. Suppose for a moment that in fact they were the same thing. Now, to who do they *seem* different? The subject is able to recognise the phenomenal description but not the neural one: the neurosurgeon however is able to recognise both. Its true he can't know if the phenomenal description is accurate without asking the subject, but he knows what the description *means*; this is how the surgeon is able to communcate with the patient: he prods area 12, the patient says 'my toe hurts', and the surgeon is able to understand the patients's phenomenal description of the event. I see no barrier here to saying that the area-12 activity IS the toe-pain felt by the patient. To her, it feels like a pain in her toe, of course; but then she has a rather special relationship to this activity, since its happening in her brain. >The question that I have is whether this distinction between "is" and "is >necessary and sufficient for" is all that important. It seems to me to be a >philosophical issue that can't ever be decided by any experiment. It has to >do with the meaning of "is". Different people can have different definitions. Not usually. >I think Pat is fine with the "necessary and sufficient for" way of saying it. >Because of Pat's enjoyment for tweaking others he likes to push the "is" >(identity) way of saying it. I am not too worried about that since he has his >own definition of "is" that differs from mine. Then you should tell us yours, because I mean the universally accepted notion: 'A is B' is true iff 'A' and 'B' denote the same thing. Nothing mysterious or unusual. The reason I dont like the 'necc and suff for' is that I see no reason for it. Here are two descriptions of events. They are always exactly correlated: whenever one occurs, so does the other. They always occur in exactly the same place at the same time. They have the same functional role. There is no way to ever distinguish them except by the language used to refer to them with. Doesnt the suspicion just creep upon you that they might, possibly, be the *same thing*? (Be brave! ;-) 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 ----------------------------------------------------------------------