  is not, even though intuitively both are true, necessary, knowable a priori, and analytic. What is the significance of the distinction we are making between them in calling one but not the other “logically true”? A principled demarcation of logical constants might offer an answer to this question, thereby clarifying what is at stake in philosophical controversies for which it matters what counts as logic (for example, logicism and structuralism in the philosophy of mathematics).