A Reverse Analysis of the Sylvester-Gallai Theorem

نویسنده

  • Victor Pambuccian
چکیده

Reverse analyses of three proofs of the Sylvester-Gallai theorem lead to three different and incompatible axiom systems. In particular, we show that proofs respecting the purity of the method, using only notions considered to be part of the statement of the theorem to be proved, are not always the simplest, as they may require axioms which proofs using extraneous predicates do not rely upon.

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عنوان ژورنال:
  • Notre Dame Journal of Formal Logic

دوره 50  شماره 

صفحات  -

تاریخ انتشار 2009