Cut/notes.html
author Christian Urban <christian dot urban at kcl dot ac dot uk>
Fri, 27 Sep 2013 14:27:21 +0100
changeset 235 e19069c38c61
parent 98 e10eb390c103
permissions -rw-r--r--
updated links

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<TITLE> Christian Urban </TITLE>
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<B>Links</B><BR>
<A HREF="http://www4.in.tum.de/~urbanc/index.html">Home</A><BR>
<A HREF="http://www4.in.tum.de/~urbanc/Cut/cutapplet.html">Applet Home</A><BR><BR>

<B>Java Versions</B><BR>
<A HREF="http://www4.in.tum.de/~urbanc/Cut/CL.html">CL</A><BR>
<A HREF="http://www4.in.tum.de/~urbanc/Cut/LJT.html">LJT</A><BR>
<A HREF="http://www4.in.tum.de/~urbanc/Cut/ND.html">ND</A><BR><BR>

<B>Plugin Versions</B><BR>
<A HREF="http://www4.in.tum.de/~urbanc/Cut/CL-plugin.html">CL</A><BR>
<A HREF="http://www4.in.tum.de/~urbanc/Cut/LJT-plugin.html">LJT</A><BR>
<A HREF="http://www4.in.tum.de/~urbanc/Cut/ND-plugin.html">ND</A><BR>

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<BR>

<A HREF="http://isabelle.in.tum.de/nominal/">
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<H2>What is the Semantics for Classical Logic?</H2>

In the intuitionistic case, the answer to this question is well-understood -
essentially a semantics is given to all proofs in normal form and all other
proofs inherit this semantics from the normal forms they reduce to. This 
implies that:

<blockquote>
(1) reductions preserving the semantics of a proof. 
</blockquote>


It is widely known that this assumption causes any reasonable semantics 
for classical logic to collaps. In the literature Lafont's example is
often cited for this observation.<p>  

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