How far can consistent assessment capture all the worthwhile features of educational achievement? Are some important components of learning "necessarily" open to a range of potentially inconsistent judgments by different assessors? I argue for a cautiously affirmative answer to this question, drawing on analogies with aesthetic judgments and a rehearsal of the holistic characteristics of some assessment criteria. I also employ recent treatments of moral particularism and of concepts of incommensurability to oppose the drive for consistency in assessment required by a high stakes accountability regime.