In this paper, I consider Isaac Newton’s fevered accusation that John Locke is a ‘Hobbist.’ I suggest a number of ways in which Locke’s account of the mind–body relation could plausibly be construed as Hobbesian. Whereas Newton conceives of the human mind as an immaterial substance and venerates it as a finite image of the Divine Mind, I argue that Locke utterly deflates the religious, ethical, and metaphysical significance of an immaterial soul. Even stronger, I contend that there is good reason to suspect that Locke is a crypto-materialist, at least with respect to human beings, and in this respect, could reasonably be labeled a ‘Hobbist.’