Path: utzoo!attcan!uunet!ncrlnk!ncrcae!hubcap!gatech!udel!princeton!njin!aramis.rutgers.edu!elbereth.rutgers.edu!harnad From: harnad@elbereth.rutgers.edu (Stevan Harnad) Newsgroups: comp.ai Subject: Re: Categorization Summary: Judging membership typicality presupposes judging membership Message-ID: Date: 14 Jan 89 08:31:31 GMT References: <2995@uhccux.uhcc.hawaii.edu> Organization: Rutgers Univ., New Brunswick, N.J. Lines: 24 lee@uhccux.uhcc.hawaii.edu (Greg Lee) of University of Hawaii writes: " We thought [Harnad] was defending his theory when he was actually just " reiterating it... He proposes that all-or-none categories are in " people's heads and that typicality judgements are made with reference " to these. *If* that's so, then typicality judgements obviously " presuppose all-or-none categories... [but if not...] No, I OBSERVE from people's performance data that (1) they can reliably sort certain instances into all-or-none categories such as "bird." I infer that (2) something in their heads is responsible for their success. I read that (3) people can also make judgments of how typical these instances are OF THE CATEGORIES OF WHICH THEY SUCCESSFULLY JUDGE THEM TO BE MEMBERS, such as "bird." I note that (3) presupposes (1) and hence conclude that (3) too depends on (2). But if any of this sounds implausible, I'm open to alternative proposals... -- Stevan Harnad INTERNET: harnad@confidence.princeton.edu harnad@princeton.edu srh@flash.bellcore.com harnad@elbereth.rutgers.edu harnad@princeton.uucp BITNET: harnad@pucc.bitnet CSNET: harnad%princeton.edu@relay.cs.net (609)-921-7771