ABSTRACT
Epicureanism and Stoicism were revisionary philosophical programs. Both required reliable criteria for the truth of their respective revisions. The Epicureans held that all sensations were true, and the Stoics held that one should believe only on the basis of what they’d called kataleptic impressions. Skeptical critique of the Epicurean criterion started with the fact that sensations vary significantly so cannot all be true, and it culminates with a challenge to the coherence of Epicurean epistemology. Skeptical critique of the Stoics’ criterion begins with the possibility of false impressions that are indiscernible from ones that are true, and it ends with the observation that if Stoics truly practiced their epistemology, they would be skeptics.
