  We have seen that in LTL Ayer maintained that all necessary truths were true in virtue of the meanings of the terms used in expressing them, this in turn depending on the conventions governing the use of those terms. One can see in the expression of this early view unease about the source of logical necessity. He describes the necessity of logical truths as dependent on the rules governing the use of logical constants. Although such rules are neither true nor false, they elucidate the “proper” use of such constants, a formulation suggesting that the source of the necessity is deeper than mere linguistic usage.