This paper reopens the debate on the possibility that Aquinas borrowed his tertia via from a Latin translation of Maimonides ‘Guide for the Perplexed’. After introducing the text of the tertia via, I shall analyze the first part and conclude that while a ‘metaphysical’, tenseless reading is correct, we should not be nervous to call Aquinas’s reasoning for what it is: flawed. Framing the problematic passage in its historical context, I shall then argue that the flaw lies not so much with Aquinas, but with the source he was borrowing from. This is Maimonides’ Dalālat al-ḥāʾirīn (“The Guide for the Perplexed”), and in fact more specifically the blame is to be given to an early translator into Latin.