 Third, both Sellars and McDowell claim that it is simply a mistake to think that mental states that are purely the upshot of causal interactions with the world could themselves stand as reasons for empirical belief. Sellars (1963) remarks that such a mistake is “of a piece with the so-called ‘naturalistic fallacy’ in ethics” (146). Sellars himself gives no clear argument for this claim. McDowell focuses on the distinction between the kind of mental state for which its bearer is in some way responsible, such as a belief, and the kind of state that simply happens to one, like a headache (McDowell 1996: chs. 1–2; 1998: 433–434; 2004: 80–85; cf. Engstrom 2006: 8–13). The suggested parallel in an Intellectualist reading of Kant is that if intellectual capacities are necessary for the occurrence of perceptual experience, then experience is not merely something that causally happens to the subject but rather is something for which the subject herself is at least partially responsible, in much the same way that she is responsible for her endorsement in belief of the content of a propositional judgment. It is certainly a centrally held tenet of Kant’s critical view that the intellect, including understanding and reason, actively contributes to the content of cognition and the acquisition of knowledge (Paton 1947: 218; Pippin 1987; Allison 1990, 1996: chs. 4, 7 and 9; Willaschek 2006; McLear 2020b). As Kant famously says,