Abstract

It is obvious that two contingent statements, each of which denies the existence of something, can be inconsistent with one another: for example, ‘There are no non-black ravens, and there is at least one raven’, and ‘There are no black ravens’. But it is also obvious that these two statements are inconsistent only because one of them, as well as denying the existence of something, asserts the existence of something. The mere denials of existence, ‘There are no non-black ravens’ and ‘There are no black ravens’, are consistent with one another. Indeed, it must hold quite generally that two contingent statements cannot be inconsistent, where each is a mere denial of existence in the sense that it denies existence and does not also assert existence. For in order to be inconsistent with a mere denial of existence, a second statement must assert existence, whatever else it may do; and if it asserts existence, it is not itself a mere denial of existence