Switch to: References

Add citations

You must login to add citations.
  1. For Want of an ‘And’: A Puzzle about Non-Conservative Extension.Lloyd Humberstone - 2005 - History and Philosophy of Logic 26 (3):229-266.
    Section 1 recalls a point noted by A. N. Prior forty years ago: that a certain formula in the language of a purely implicational intermediate logic investigated by R. A. Bull is unprovable in that logic but provable in the extension of the logic by the usual axioms for conjunction, once this connective is added to the language. Section 2 reminds us that every formula is interdeducible with (i.e. added to intuitionistic logic, yields the same intermediate logic as) some conjunction-free (...)
    Download  
     
    Export citation  
     
    Bookmark   2 citations  
  • Glivenko like theorems in natural expansions of BCK‐logic.Roberto Cignoli & Antoni Torrens Torrell - 2004 - Mathematical Logic Quarterly 50 (2):111-125.
    The classical Glivenko theorem asserts that a propositional formula admits a classical proof if and only if its double negation admits an intuitionistic proof. By a natural expansion of the BCK-logic with negation we understand an algebraizable logic whose language is an expansion of the language of BCK-logic with negation by a family of connectives implicitly defined by equations and compatible with BCK-congruences. Many of the logics in the current literature are natural expansions of BCK-logic with negation. The validity of (...)
    Download  
     
    Export citation  
     
    Bookmark   13 citations  
  • Glivenko like theorems in natural expansions of BCK‐logic.Roberto Cignoli & Antoni Torrens Torrell - 2004 - Mathematical Logic Quarterly 50 (2):111-125.
    The classical Glivenko theorem asserts that a propositional formula admits a classical proof if and only if its double negation admits an intuitionistic proof. By a natural expansion of the BCK‐logic with negation we understand an algebraizable logic whose language is an expansion of the language of BCK‐logic with negation by a family of connectives implicitly defined by equations and compatible with BCK‐congruences. Many of the logics in the current literature are natural expansions of BCK‐logic with negation. The validity of (...)
    Download  
     
    Export citation  
     
    Bookmark   14 citations