In this chapter, I try to reconcile an inconsistency between Sellars’s ethical theory and his larger philosophical project. Sellars rejects formalism in theoretical reasoning, arguing

This dry, well-made match is struck

Therefore, the match will light

is a good inference and doesn’t depend for its validity on the insertion of a major premise. In ethics, though, Sellars seems to embrace this formalism, arguing

I am in C_i

Therefore, Shall_we [I do A_i]

is good qua instantiation of the intermediate moral principle

Shall_we [I do A_i if in C_i]

which in turn is good only if derived from the supreme principle of morality

Shall_we be [Our welfare is maximized]

This formalism is inconsistent with Sellars’s other commitments. We should recognize that intermediate moral principles have original (but not foundational) authority; they are “auxiliary moves,” as described in “Some Reflections on Language Games.” But there is still a role for the supreme principle of morality: It is a theoretical postulate that serves a dialectical role to resolve disputes among mid-level intermediate moral principles and to bring consistency into our moral practice. Thus, we can preserve the formal structure of Sellars’s ethical theory while preserving his opposition to formalism per se.