And while I was listening in to what they were talking about, one of them let out a guffaw: “Stop,” he said, “lying your way into words as absurd and monstrous as these.”

We come in on the middle of an argument. The story the first man has just told is never repeated for us; we hear only the second man’s verdict, “absurd and monstrous.” Lewis & Short’s first sense of absurdus is “out of tune, hence giving a disagreeable sound, harsh, rough,” and among its relatives it lists susurrus, the “whisper” the prologue offered in 1.1. The skeptic hears in the tale a sound out of tune. Parce … mentiendo is the verb parcere, “to spare,” with what is to be spared in the ablative: “spare us the lying,” that is, “stop lying.” Lewis & Short lists the sense “to abstain or refrain from doing a thing; to forbear, leave off, desist, stop.” Cachinnus is loud laughter: “immoderate laughter, a laugh in derision, a jeering.”