Are Tableaux an Improvement on Truth-Tables? Cut-Free proofs and Bivalence
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چکیده
We show that Smullyan's analytic tableaux cannot p-simulate the truth-tables. We identify the cause of this computational breakdown and relate it to an underlying semantic diiculty which is common to the whole tradition originating in Gentzen's sequent calculus, namely the dissonance between cut-free proofs and the Principle of Bivalence. Finally we discuss some ways in which this principle can be built into a tableau-like method without aaecting its \analytic" nature.
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تاریخ انتشار 1992