 Some philosophers also make use of the notion of moral certainty (see Markie 1986; James 2020). For example, in the Latin version of Part IV of the Principles of Philosophy, Descartes says that “some things are considered as morally certain, that is, as having sufficient certainty for application to ordinary life, even though they may be uncertain in relation to the absolute power of God” (PW 1, pp. 289–90). Thus characterized, moral certainty appears to be epistemic in nature, though it is a lesser status than epistemic certainty (see Matthen 2014 for a similar account of what he calls “empirical certainty”). In the French version of this passage, however, Descartes says that “moral certainty is certainty which is sufficient to regulate our behaviour, or which measures up to the certainty we have on matters relating to the conduct of life which we never normally doubt, though we know that it is possible, absolutely speaking, that they may be false” (PW 1, p. 289 n. 2). Understood in this way, it does not appear to be a species of knowledge, given that a belief can be morally certain and yet false (contra Markie 1986, p. 36). Rather, on this view, for a belief to be morally certain is for it to be subjectively rational to a high degree. In a similar way, Spinoza distinguishes moral certainty from mathematical certainty and says that the former should not be rejected when “it is confirmed by the testimonies of so many prophets, is a source of great solace for those whose capacity to reason is limited, is of great value to the state, and may be believed unreservedly without danger or damage” (Tractatus Theologico-Politicus, ch. 15; see James 2020, ch. 1). Moral certainty understood in this way is not merely a form of psychological certainty, as someone who has the highest degree of confidence in a particular claim might nevertheless do so for manifestly irrational or frivolous reasons.