These gnomes or maxims were extended and put into literary shape by the poets. Fragments of Solon, Euenus, and Mimnermus have been preserved, in a very confused state, from having been written, for purposes of comparison, on the margins of the manuscripts of Theognis, whence they have often slipped into the text of that poet. Theognis enshrines his moral precepts in his elegies, and this was probably the custom of the rest; it is improbable that there ever existed a species of poetry made up entirely of successive gnomes. But the title gnomic came to be given to all poetry which dealt in a sententious way with questions of ethics. It was, unquestionably, the source from which moral philosophy was directly developed, and theorists upon life and infinity, such as Pythagoras and Xenophanes, seem to have begun their career as gnomic poets.