Abstract

If we accept the idea that the value of a “logic” depends on its ability to fit the usual meaning of the “logical constants” which it formalises and the inferences we draw on their basis, we may ask if the meaning of “possible” is well captured by normal modal logic. We are faced with the following puzzle: if is meaningful and non contradictory is it not a logical truth that ? First, it is shown why there is no logical law of the form , being a neutral wff, and then some philosophical conclusions are drawn: “possible” relative to truth must be distinguished from possible “relative” to meaning, and the former only is formalised in modal logic