Article View: sci.logic
Article #303Re: Russell's Paradox
From: David Gudeman
Date: Thu, 05 Nov 1992 20:22
Date: Thu, 05 Nov 1992 20:22
26 lines
1729 bytes
1729 bytes
In article <1992Nov04.233228.16942@Cookie.secapl.com> Frank Adams writes:
]In article <24780@optima.cs.arizona.edu> gudeman@cs.arizona.edu (David Gudeman) writes:
]>This (or so I claim) is the single, simple, obvious cause of Russel's
]>paradox. In particular, R = {x : x not elem x} is a definition of
]>type (2) that contains an implicit reference to R because x quantifies
]>over a set that contains R. (Or you could show the recursion in the
]>definition of elem as I did before)...
]
]It appears to me that you are complaining not about elementhood being a
]proposition, but about the unrestricted range of the quantification in the
]axiom of comprehension. Note that your complaint about the implicit
]reference to R is just as applicable to R = {x : x = x}, which gives the
]universal set without using elementhood.
No, I am not complaining about elementhood being a proposition, I am
complaining about a syntactic circularity begin treated as though it
had semantic significance. Neither am I concerned about the
unrestricted range of the quantification. As the set {x : x = x}
clearly shows, there is no inconsistency inherent in either
self-membership or impredicativity. I claim that {x : x = x} is a
perfectly reasonable set and that the mere fact that ZF proves the
opposite is enough to show that ZF is not an adequate axiomatization
of set theory.
--
David Gudeman
gudeman@cs.arizona.edu
Technical Details
Message-ID:
<25916@optima.cs.arizona.edu>Path:
arc1-ca.pugleaf.net!sparky!uunet!destroyer!ncar!noao!arizona!gudemanShow Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!sparky!uunet!destroyer!ncar!noao!arizona!gudeman From: gudeman@cs.arizona.edu (David Gudeman) Newsgroups: sci.logic Subject: Re: Russell's Paradox Message-ID: <25916@optima.cs.arizona.edu> Date: 5 Nov 92 20:22:02 GMT Organization: U of Arizona CS Dept, Tucson Lines: 26