What Optimistic Responses to Deep Disagreement get Right (and Wrong)

In this paper, I argue for three theses. First, that the problem of Deep Disagreement is usefully understood as an instance of the skeptical Problem of the Criterion. Second, there are structural similarities between proposed optimistic answers to deep disagreement and the problem of the criterion. Third, in light of these similarities, there are both good and bad consequences for proposed solutions to the problem of deep disagreement.