  However, even if the rules are not “definitions,” there may still be something to say for the claim that they “fix the senses” of the constants they introduce. For it may be that a speaker’s grasp of the meaning of the constants consists in her mastery of these rules: her disposition to accept inferences conforming to the rules as “primitively compelling” (Peacocke 1987, Hodes 2004). (A speaker finds an inference form primitively compelling just in case she finds it compelling and does not take its correctness to require external ratification, e.g. by inference.) If the senses of logical constants are individuated in this way by the conditions for their grasp, we can distinguish between truth-functionally equivalent constants with different meanings, like \(\dq{\vee}\), \(\dq{\ddagger}\), and \(\dq{\dagger}\), as defined below: