Internal Reasons and Contractualist Impartiality

This paper interprets Bernard Williams's claim that all practical reasons must meet the internal reasons constraint. It is argued that this constraint is independent of any substantive Humean claims about reasons and its rationale is a content scepticism about the capacity of pure reason to supply reasons for action. Conversely, the argument can be interpreted as about what we are entitled to assume, for free, about the very idea of a practically rational agent. Hooker's and Korsgaard's critiques of Williams are considered and rejected as not considering sufficiently the prior commitment to content scepticism. The dispute between Williams and McDowell is separately discussed and identified in terms of psychologism, which Williams was happy to adopt for practical reasons, McDowell not, and whether appeal to the content of the reasons of a phronimos gives any purchase on the contents of an agent's reasons. It is argued that it does not and that McDowell's account of external reasons involves illegitimate idealisation. The final sections attempt a positive reconciliation of the internal reasons account with the motivation for external reasons, namely, securing practical objecitivy in the form of a commitment to impartiality. Impartiality is given a contractualist interpretation in the limited sense that socialised agents have a central disposition to hold those reasons that are defensible to reasonable interlocutors, but this is not a substantive constraint on their content.