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3 <TITLE> Christian Urban </TITLE> |
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4 <BASE HREF="http://www4.in.tum.de/~urbanc/"> |
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28 |
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29 <B>Links</B><BR> |
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30 <A HREF="http://www4.in.tum.de/~urbanc/index.html">Home</A><BR> |
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31 <A HREF="http://www4.in.tum.de/~urbanc/Cut/cutapplet.html">Applet Home</A><BR><BR> |
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32 |
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33 <B>Java Versions</B><BR> |
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34 <A HREF="http://www4.in.tum.de/~urbanc/Cut/CL.html">CL</A><BR> |
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35 <A HREF="http://www4.in.tum.de/~urbanc/Cut/LJT.html">LJT</A><BR> |
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36 <A HREF="http://www4.in.tum.de/~urbanc/Cut/ND.html">ND</A><BR><BR> |
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37 |
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38 <B>Plugin Versions</B><BR> |
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39 <A HREF="http://www4.in.tum.de/~urbanc/Cut/CL-plugin.html">CL</A><BR> |
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40 <A HREF="http://www4.in.tum.de/~urbanc/Cut/LJT-plugin.html">LJT</A><BR> |
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41 <A HREF="http://www4.in.tum.de/~urbanc/Cut/ND-plugin.html">ND</A><BR> |
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42 |
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43 <BR> |
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44 <BR> |
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45 |
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46 <A HREF="http://isabelle.in.tum.de/nominal/"> |
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51 |
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52 <!-- right column --> |
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53 <TD BGCOLOR="#FFFFFF" WIDTH="75%"> |
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54 |
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55 <H2>What is the Semantics for Classical Logic?</H2> |
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56 |
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57 In the intuitionistic case, the answer to this question is well-understood - |
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58 essentially a semantics is given to all proofs in normal form and all other |
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59 proofs inherit this semantics from the normal forms they reduce to. This |
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60 implies that: |
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61 |
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62 <blockquote> |
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63 (1) reductions preserving the semantics of a proof. |
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64 </blockquote> |
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65 |
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66 |
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67 It is widely known that this assumption causes any reasonable semantics |
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68 for classical logic to collaps. In the literature Lafont's example is |
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69 often cited for this observation.<p> |
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70 |
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71 <center> |
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79 </center><p> |
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80 |
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81 |
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82 </TD> |
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84 |
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85 </TABLE> |
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86 <P><!-- Created: Tue Jul 3 21:01:42 BST 2001 --> |
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87 <!-- hhmts start --> |
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88 Last modified: Sat Mar 3 05:17:53 CET 2007 |
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