  The final portion of On Signs III is all we have of the work, the full title of which was apparently On Phenomena and Sign-inferences (sêmeiôseôn). It comprises four sections (labeled here §§1–4, followed by column and line numbers from DeLacy and DeLacy 1978) and reports the ways in which three Epicureans responded to criticisms of their theory of sign-inference. First is Philodemus’ teacher, Zeno (§1, §2); then Demetrius Laco (§3, xxviii 13–xxix 19), whose interest in proof is known from Sextus (M 8.348); and finally another, unnamed, colleague (§4, xxix 20–xxxviii 22). The authors of the initial criticisms are unknown, but probably include the Dionysius who is named as author of replies to the Epicurean rebuttals of the first round of criticisms (§1, vii 5–viii 21; Zeno’s replies occupy viii 21–ix 26), and he may be a Stoic or Peripatetic. On the other hand, the method favored by the opponents, EM or the elimination mode (anaskeuê, which is not the same as contraposition, as scholars used to think), is not positively attested as Stoic.