Unique Normal Proof Property for Implicational Minimal Formulas in the Intuitionistic Logic
نویسنده
چکیده
A formula is said to have unique-normal proof property and unique-normal proof property ii it has a unique-normal proof and a-normal proof in NJ, respectively. In this report a condition of implicational minimal formulas in the intuitionistic logic for unique-normal proof property is presented making use of unique-normal proof property for negatively non-duplicated formulas. It is shown that this condition properly includes both BCK-provability and depth 2 which are previously known conditions.
منابع مشابه
Uniqueness of Normal Proofs in Implicational Intuitionistic Logic
A minimal theorem in a logic L is an L-theorem which is not a nontrivial substitution instance of another L-theorem. Komori (1987) raised the question whether every minimal impli-cational theorem in intuitionistic logic has a unique normal proof in the natural deduction system NJ. The answer has been known to be partially positive and generally negative. It is shown here that a minimal implicat...
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تاریخ انتشار 1995