 It would be absurd to deny that Grotius does rely “on the poets”—after all, he said in the “Prolegomena” to the DIB that “the testimony of philosophers, historians, poets, finally also of orators” will be used to “prove the existence of this law of nature” (§40). Arguments from authority carried great weight for him: the more illuminati one could cite, the better for one’s argument. Philosophers today may not be impressed by such arguments, though they can be instructive to historians of philosophy. By studying Grotius’ use of texts, one can learn how they were interpreted in the early modern period—and this can unlock one of the many barriers to understanding that time.