This chapter looks again at the Carneadean pithanon. It is proposed that in the Carneadean scheme an impression's initial persuasiveness, prior to any testing or scrutiny, is taken to be due to the fact that its propositional content is consistent with views antecedently held by the subject, and that an impression's phenomenal clarity is an enabling not a constitutive property of persuasiveness as conceived by Carneades. Alternative interpretations are rejected: that the initial persuasiveness of a persuasive impression is a brute fact, not capable of explanation; that it is exclusively or primarily due to the phenomenal clarity of an impression; or that it is linked to probability, pre-theoretical or otherwise. The argument is developed with reference to evidence from Sextus and then tested against evidence from Cicero; the Stoic conception of the pithanon is considered for comparison.