Aside from Greene's remarkable versatility and rapidity of workmanship,[4] his most striking characteristic as an author is his ability immediately to adapt himself to the changing literary demands of the hour. This will be seen to have particular significance in connection with the question of the chronology of his plays, yet it is pertinent here as pointing the dividing line between his earlier and later interests in composition. At the end of _Never too Late_ (1590) Greene says, "And therefore as soon as may be, gentlemen, look for Francesco's further fortunes, and after that my _Farewell to Folly_, and then adieu to all amorous pamphlets." And in the dedication of _Francesco's Fortunes_ (Part II. of _Never too Late_) he advised his gentlemen readers to look for "more deeper matters." So also at the end of his _Mourning Garment_ (1590) Greene announces that he will write no more love pamphlets. This work must serve as the first-fruits of his new labours and the last farewell to his fond desires. Again, in the dedicatory epistle to _Farewell to Folly_, licensed in 1587 but not published until 1591, about which time it is reasonable to suppose the epistle was written, he says this is "the last I mean ever to publish of such superficial labours." That he is sincere in this promise is clear from the fact that, while he published _Philomela_ in 1592, he is careful in doing so to explain that it had been hatched long ago and was now given his name at the solicitation of his printer. We have here fixed a point about the year 1590 for the beginning of new and more serious work. Two theories have been advanced to explain the nature of this work. The one theory, which has among its adherents Collins, the latest editor of Greene's complete plays, supposes that Greene must refer to the beginning of his play-writing. Against this theory there are the strong objections that Greene must have written plays before he made any promise to engage in more serious writing, the strong circumstantial and internal evidence that several of the extant plays ante-date such a promise, and the no less significant fact that Greene had no pride in his work as a playwright and no respect for the calling as a serious occupation. The second theory is that Greene had long contemplated the exposure of the arts and devices of the under-world of prey, and that the year 1590 represents approximately the time at which he ceased the composition of romantic and mythologising pamphlets, which associated him with Lyly and Sidney and the more affected of the university writers, and began the composition of realistic studies in the rogue society of his own time. There is no reason to suppose that Greene was not sincere in his desire to present an edifying picture of the dangers surrounding London youth and the weaknesses and vanities in English society.[5]