Are all forms of difference contained in what is, or is there some form of difference that escapes, negates, or constitutes what is? Parmenides and Heraclitus may have had the greatest effect on how philosophy has answered this question. This paper shows that Heraclitus is not a partisan of difference: identity and difference are mutually generative and equally fundamental. For his part, Parmenides both makes an argument against opposing being and non-being in the False Road Story, and then uses precisely (...) this opposition to put up signs on the Way of Truth. The paper responds to this impasse by making the case that the poem’s philosophical character is didactic, rhetorical, and mythological, which is why both these signs, and the opposition between non-being and being, are presented as names created by mortals. (shrink)