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In article <1993Mar18.104242.3055@etl.go.jp> yoshiki@etl.go.jp
(KINOSHITA Yoshiki) writes:

 |$@!V=89gO@$r!J=89gO@0J30$N!K?t3X$N4pAC$H$9$k$3$H$K5?Ld(J$@$,$"$k!W$H$$$&4QE@(J
 |$@$+$i!"(Jnon-well-founded set $@$X$N(J objection $@$H$7$F<!$NO@J8$,LLGr$+$C$?$N(J
 |$@$G>R2p$7(J$@$^$9!#(J
 |
 |	  Michael Barr: Functional set theory
 |
 |	  FTP-able from `triples.math.mcgill.ca' (132.206.150.30),
 |	  directory `Barr', file `math_intelligencer.ps'
 |
 |Mathematical intelligencer $@$H(J$@$$$&;(;o$K=P$?5-;v$N$h$&$G$9!#(J

$@$3$l$OLLGr$=$&$G$9$M!#9qFb$N$I$3$+$+$i(J FTP $@$G$-$J$$$N$G$7$g$&$+!#:#(J 
archie $@$7$F$_$?=j$G$O$=$l$i$7$$$N$O$J$$$h$&$G$9$,!#(J

 |Barwise & Moss $@$K$h$k!V(JA$@!_(JX$@!a(JX $@$N$h$&$JNN0hJ}Dx(J$@<0$r(J non-well-founded
 |set $@$G2r$1$k$h!W$H$$$&O@J8$rFI$s$G!"(J
 |
 |	  The purpose of this note is to suggest that the whole
 |	  enterprise is wrong-headed
 |
 |$@$H$$$&$3$H$@$=$&$G$9!#6/Nu$d$J$"!#(JNon-well-founded sets $@$G$NK\Ev$NLdBj(J

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 |$@E@$O!"(J
 |
 |	  the irrelevance of actual elements in mathematics
 |
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 |$@%9!\&A!K!"$=$N8xM}$N$b$H$GNN0hJ}Dx<0$r2r$$$F$_$;$F$$$^$9!#$3$l<+BN$O0l(J
 |$@Dj$N>r7o$rK~$?$97w$G(J$@NN0hJ}Dx<0$r2r$/$H$$$&$3$H$G!"FC$KL\?7$7$/$O$"$j$^(J
 |$@$;$s$,!"$H$K$+$/(J non-well-founded set $@$K$h$k0J30(J$@$N2r$K$J$C$F$$$^$9!#!_(J
 |$@!\"*$/$i$$$+$i$J$kNN0hJ}Dx<0$J$i(J Scott $@M}O@$G$b2r$1$^$9$,!#(J

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$@4[$+$i<Z$j$F$$(J$@$?$1$l$IJV$7$F$7$^$$$^$7$?(J)$@$N$G!"$h$/$o$+$j$^$;$s$1$I!D!#(J
classical logic $@$G9M$($F$$$k$+$iG;EY$r9M$($k(J$@$H$@$a$J$h$&$J!D!#(JScott $@M}(J
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$@$h$&$JJ}Dx<0$K2r$,$"$k$h$&$J=89gO@$N%b%G%k$,$"$k(J$@!"$H$$$&$N$O$@$s$V$sA0(J
$@$+$iCN$i$l$F$$$k;v$@$H;W$$$^$9!#;d$,6=L#$,$"$k$N$O!">e$N(J Barr $@$5$s$N$d(J
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$@M}$,%Y!<%9$J$N$+$b!D!#(J

 |$@=89g$G$d$k$H!"6qBNE*$9$.$k!"(Jsets have too much structure $@$H$$$&$N$,H`(J
 |$@$N7kO@$G$9!#(J

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--
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satoshi@rins.ryukoku.ac.jp            | <- $@%"%I%l%9$rJQ$($^$7$?$,!"EvJ,$O(J
0775-43-7523($@3X2J;vL3(J$@<<(J) 7528($@8&5f<<(J) |    $@A0$N(J satoshi@whale.ryukoku.ac.jp
        7524(FAX)                     |    $@$G$b(J$@FO$-$^$9!#(J