Recommended translation: "Epinomis," trans. W. R. M. Lamb in Plato in Twelve Volumes, vol. 9, Cambridge, MA: Harvard University Press, 1925.
Excerpt:
Cleinias: True to our agreement, good sir, we have come all three—you and I and Megillus here—to consider in what terms we ought to describe that part of understanding which we say produces, when it so intends, the most excellent disposition of the human being for wisdom which is possible for man. For we claim that we have described all the other matters connected with law-giving; but the most important thing for us to discover and state—what it is that mortal man should learn in order to be wise—this we have neither stated nor discovered. Let us, however, now try to make good this defect: else we shall practically leave incomplete the quest on which we all set out, with the purpose of making our subject clear from beginning to end.