Cornford, Francis MacDonald, Plato and Parmenides: Parmenides' Way of Truth and Plato's Parmenides, Kegan Paul, Trench, Trubner & Co., 1939; repr. Routledge, 2010.

Excerpt:

Parmenides was likely written within the last two decades preceding Plato’s death in 347 BCE. Despite two millennia of documented commentary, scholars struggle to make sense of it. Almost every major discussion of the Parmenides in this century has begun with some remark about its extraordinary difficulty & no interpretation has yet been offered that a majority of commentators find persuasive.

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