This article seeks to determine the basis for judgments on works of art in the writings of the art historian and critic Benjamin Buchloh. I argue that Buchloh’s judgments are not Kantian aesthetic judgments, nor are they consequentialist moral or political judgments as to the positive or negative effects of artworks. Rather, Buchloh’s judgments are based upon an implicit principle of ‘legitimacy’ or ‘credibility’ that is distinct from the mere possibility of specific artistic practices. I identify several factors that, for Buchloh, are involved in determining the legitimacy of any work of art. In the process I highlight apparent contradictions that result from Buchloh’s rhetoric, specifically his tendency to conflate constitutive conditions of possibility with normative value judgments. For Buchloh, it is only through a successful negotiation of these factors that an artwork succeeds in constituting itself as a meaningful ‘enunciation’ within the structuring system of artistic practice at a given moment.