Bop and TUurlijk http:logica'ewi'tudelft'nl

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Bop and TUurlijk _at_http//logica.ewi.tudelft.nl

• Sicco Verwer, Mathijs de Weerdt, Jonne Zutt
• Delft University of Technology

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Content

• Network structure
• Gaps and what to ask the prover
• Algorithm used by TUurlijk
• Returning our answer to the client

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Network structure
http//logica.ewi.tudelft.nl
Client 1
Web server xinetd service
Client 2
Applicationserver 1
Client 3
Applicationserver 1
Client N
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Fitch theorem prover - Gaps

• a ? (b ? c), b, a, b ? c c

(a ? (b ? c)) ? (b ? (a ?c))
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Algorithm

• Forward reasoning
• Constructive proofs usually more intuitive and
  shorter
• Quickly terminates, no recursion needed
• Backward reasoning
• Recursion required, slow
• Or-elimination and proof by contradiction

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Portoraro

• Reiterations
• Eliminations (excluding or-eliminations,
  including or-introductions)
• Introductions
• Or-elimination
• Contradiction

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Answer back to the client

• Proof just show the full proof in a separate
  window.
• Step the algorithm tracks which steps are
  used, reply the first step to the client
  (Portoraro order).
• Hint convert a step into text.