It will be seen from these discussions that the Renaissance always conceived of aesthetic imitation in this ideal sense. There are scarcely any traces of realism, in anything like its modern sense, in the literary criticism of this period. Torquato Tasso does indeed say that art becomes most perfect as it approaches most closely to nature;[56] and Scaliger declares that the dramatic poet must beyond all things aim at reproducing the actual conditions of life.[57] But it is the appearance of reality, and not the mere actuality itself, that the critics are speaking of here. With the vast body of mediaeval literature before them, in which impossibilities follow upon impossibilities, and the sense of reality is continually obscured, the critical writers of the Renaissance were forced to lay particular stress on the element of probability, the element of close approach to the seeming realities of life; but the imitation of life is for them, nevertheless, an imitation of things as they ought to be--in other words, the imitation is ideal. Muzio says that nature is adorned by art:-- "Suol far l' opere sue roze, e tra le mani Lasciarle a l' arte, che le adorni e limi;"[58] and he distinctly affirms that the poet cannot remain content with exact portraiture, with the mere actuality of life:-- "Lascia 'l vero a l' historia, e ne' tuoi versi Sotto i nomi privati a l' universo Mostra che fare e che non far si debbia." In keeping with this idealized conception of art, Muzio asserts that everything obscene or immoral must be excluded from poetry; and this puristic notion of art is everywhere emphasized in Renaissance criticism. It was the _verisimile_, as has been said, that the writers of this period especially insisted upon. Poetry must have the appearance of truth, that is, it must be probable; for unless the reader believes what he reads, his spirit cannot be moved by the poem.[59] This anticipates Boileau's famous line:-- "L'esprit n'est point emu de ce qu'il ne croit pas."[60] But beyond and above the _verisimile_, the poet must pay special regard to the ethical element (_il lodevole e l' onesto_). A poet of the sixteenth century, Palingenius, says that there are three qualities required of every poem:-- "Atqui scire opus est, triplex genus esse bonorum, Utile, delectans, majusque ambobus honestum."[61]