All I hope to do in this note is to reinforce Lesky's protest against ‘the attitude of mind shown by many modern scholars, who refuse to admit that there is a Prometheus problem at all, and pass over in silence so many arguments which deserve the most careful attention’. One reason why the majority of scholars are so sanguine about the peculiarities of Prometheus Desmotes is that they take it for granted that the surviving play was the first of a trilogy, and that the remainder of the trilogy would somehow or other have resolved some or most or all of the problems of the surviving part. It is assumed that the second play was, as the titles apparently proclaim, Prometheus Luomenos: the chief exception to this view is W. Schmid, the much reviled but scarcely refuted champion of the bastardy of Prom. Desm., who argued that the surviving play was written in the third quarter of the fifth century by an imitator of Aeschylus. Next it is usually supposed that Prometheus Purphoros (a title in the catalogue in M, twice cited elsewhere) was the third play—though there have been more respectable exceptions to that step. The fourth Prometheus title (twice cited by Pollux), Prometheus Purkaeus, is very plausibly taken to be the satyr play of 472 B.C., called simply Προυηθεύς in the hypothesis to Pers. Despite this, no-one seems to have questioned the easy assumption that the other three Prometheus titles are evidence for the connected trilogy. I shall offer here a neglected reason for thinking that, on the contrary, the titles are evidence that the Prometheus plays were not produced together. The argument is pedantic, even irritating, but it is nonetheless coherent and hard to contradict.