Aletik Bağıntılar Işığında Mantık Eklemlerinin Anlamları

Abstract

One of the central questions in 20th-century discussions within logic and philosophy of language is where logical constants, specifically propositional connectives, get their meaning from. What kind of determination/justification bond is found between the inference rules peculiar to a given connective and the meaning of that connective? Are these rules justified by it, or rather do they contribute to its construction? An observation made by G. Gentzen, who founded in the 1930s the proof-theoretical approach at large, triggered a view (called by some logical inferentialism) that gives a remarkable answer to the above question: the meaning of a logical constant in a logical language is provided, not by some sort of representational content, but by the inferential norms that govern its overall use. In 1960 A. N. Prior fictionalized as a counter-instance the connective tonk solely using a couple of inference rules, a connective capable of overthrowing the system of deduction; N. Belnap’s 1962 reply in the form of an analysis of the tonk problem opens the way to discussions in logic-cum-philosophy of language with important outcomes. The present little study can be read as some further deflation of the tonk problem with a relatively unconstrained inferentialistic view of the matter. The two main theses of the study are (i) that the problem posed by tonk-like connectives can be captured, more simply than in Belnap’s (otherwise correct) analysis, through inferential relations of a certain type which will be dubbed alethic relations; and (ii) that Prior’s challenge, brought to completion in whichever way, cannot give any result against the inferentialist conception.