 Lucullus has an interesting riposte to this, which involves questioning the intelligibility of being able to determine what is plausible and what is not without a criterion for determining what is true and what is not. He points out that in rejecting the cataleptic impression, the sceptic does not allow that there are impressions distinctively marked out as truth-bearing. But if so, it follows that there is no difference between true and false, in the sense that there is nothing about a given impression that will mark it out as true rather than false. So, says Lucullus, ‘there will be no criterion’ (2.34). In other words, without a means of determining which is true, no impression will be more deserving of credence than any other.