As a lurker who failed to either notice the date or understand any detail of Paul's demonstration, I appreciate Lawvere's comments. I do feel, though, that he is overstating the impact of Paul's little jest. There were several immediate replies (to the effect, I think, that F(lim X) is not lim F X), and no riposte from Paul. My own reaction was: hmm, it'll be interesting if anything else comes out of this. I sympathise very much with Paul's "anti-ZF" stance; after all, hasn't Lawvere set the basis for a non-set foundation of practical mathematics? -----Original Message----- From: cat-dist@mta.ca [mailto:cat-dist@mta.ca]On Behalf Of F W Lawvere Sent: 06 April 1999 22:41 To: CATEGORIES@mta.ca Subject: categories: Re: incompleteness of ZF Using an old logician's trick (see eg Feferman on paths thru O, or even Goedel's original papers) as an April Fool joke may be amusing to some within the closed gates of a British University, but is irresponsible on the world network. Think of the hundreds of lurkers (who hesitate to speak up so that misconceptions can be discussed and clarified openly, but) who are now furthering the rumor that mathematics has somehow been proved inconsistent.The waves of such disinformation can last for years or even decades. ************************************************************************ ******* F. William Lawvere Mathematics Dept. SUNY wlawvere@acsu.buffalo.edu 106 Diefendorf Hall 716-829-2144 ext. 117 Buffalo, N.Y. 14214, USA ************************************************************************ *******