Abstract
The problem of logical constants is viewed from the perspective of logical expressivism. Based on Ian Hacking's idea of flexible demarcation of logic the idea of various degrees of logicality of expressions is developed.
The notion of logical constant is thus rendered somewhat fuzzy but this could be seen as an asset, as it brings to a deeper evaluation of the very idea of making an inference rules explicit. The relation between the implicit and explicit has to be examined more thoroughly.
The opposition between using a rule and rendering it explicit cannot be drawn so strictly.