43 lines
878 B
XML
43 lines
878 B
XML
$( Modified version of demo0.mm from 1-Jan-04 $)
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$(
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PUBLIC DOMAIN DEDICATION
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This file is placed in the public domain per the Creative Commons Public
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Domain Dedication. http://creativecommons.org/licenses/publicdomain/
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Norman Megill - email: nm at alum.mit.edu
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$)
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$c 0 + = -> ( ) term wff |- $.
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$v t r s P Q $.
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tt $f term t $.
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tr $f term r $.
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ts $f term s $.
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wp $f wff P $.
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wq $f wff Q $.
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tze $a term 0 $.
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tpl $a term ( t + r ) $.
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weq $a wff t = r $.
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wim $a wff ( P -> Q ) $.
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a1 $a |- ( t = r -> ( t = s -> r = s ) ) $.
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a2 $a |- ( t + 0 ) = t $.
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${
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$( Define the modus ponens inference rule $)
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min $e |- P $.
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maj $e |- ( P -> Q ) $.
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mp $a |- Q $.
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$}
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th1 $p |- t = t $=
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$( Here is its proof: $)
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tt tze tpl tt weq tt tt weq tt a2 tt tze tpl
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tt weq tt tze tpl tt weq tt tt weq wim tt a2
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tt tze tpl tt tt a1 mp mp
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$.
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