 Clitomachus defended the consistency of a radical skepticism of this sort by denying that assent is necessary for action or belief, as the Stoics had claimed in their inactivity objection to the Academic corollary argument  (section 3.1  above). His defense came in two stages, both appealing to arguments Carneades had used in response to the Stoic objection. The first stage identified a way to discriminate between our thoughts without appealing to their objective status as true or as “cognitive” impressions (see Cicero Ac. 2.98–99, cf. 2.32). Here Clitomachus drew on Carneades’ “theory of probable [or, better, ‘persuasive’ (pithanon)] impressions”—i.e., the description of ordinary epistemic procedures that Carneades promoted as an alternative to the Stoic theory of cognitive impressions (see Sextus M 7. 166–89 and Allen 1994). In ordinary life, Carneades argued, we proceed without assuming that a set of what the Stoics call impressions is “cognitive” or immediately warranted to be true. Rather, some “impressions” leave us with no immediate inclination to accept them, while some strike us as subjectively “persuasive”, at least initially, owing to their internal characteristics (e.g., the richness of their representation). We can increase or diminish the initial persuasiveness of our impressions by considering the perceptual conditions under which we experience them (e.g., normal perceptual conditions for perceiving the state of affairs they represent), and their fit with our other impressions (e.g., normal coherence conditions). And we accept and act on impressions when they reach the level of persuasiveness we find appropriate to the situation we are in. But, Clitomachus insisted, none of these procedures is sufficient to establish that an impression is true or “cognitive”, since, as the Academics have argued, the representational features of any true impression can always be replicated by a false one. (See Cicero Ac. 2.98–99.) And there is no reason to think that in ordinary life we assume that the procedures are sufficient (see Plutarch Common Conceptions ch. 36).