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- Path: sparky!uunet!pipex!unipalm!uknet!news.cs.bham.ac.uk!ard
- From: ard@cs.bham.ac.uk (Antoni Diller)
- Newsgroups: sci.logic
- Subject: Re: Are all crows black?
- Message-ID: <Bx93Cw.3Iz@cs.bham.ac.uk>
- Date: 5 Nov 92 16:05:19 GMT
- References: <1992Oct30.172420.1@eagle.wesleyan.edu> <1992Nov4.184630.3575@hubcap.clemson.edu>
- Sender: news@cs.bham.ac.uk
- Organization: School of Computer Science, University of Birmingham, UK
- Lines: 22
- Nntp-Posting-Host: fattie
-
- In article <1992Nov4.184630.3575@hubcap.clemson.edu> steve@hubcap.clemson.edu ("Steve" Stevenson) writes:
- >skumar@eagle.wesleyan.edu writes:
- >
- >>Please correct me if I am wrong but I think that if I found a creature which
- >>was like a crow in all respects but it was white in color, I would call it an
- >>albino crow or something. I would not call it just "a crow". Does this not mean
- >>that we accept "all crows are black" by definition so we need not prove it?
- >
- >Isn't this the "grue" problem? The "grue" problem came about (if I remember
- >correctly) because all emeralds were green and believed by reputable scientists
- >that they could only be green. Then they found blue ones...
- >
- >--
- >===============================================================================
- >Steve (really "D. E.") Stevenson steve@hubcap.clemson.edu
- >Department of Computer Science, (803)656-5880.mabell
- >Clemson University, Clemson, SC 29634-1906
-
- `Grue' was an invented word by Nelson Goodman; something is grue if it is
- green before 1 January 2000 and blue thereafter; therefore every confirmation
- of the sentence `all Xs are green' is also a confirmation of the
- sentence `all Xs are grue' (before 2000).
-