Trissino (1563) first introduced the Aristotelian theory of the epic into modern literary criticism; and the sixth section of his _Poetica_ is given up almost exclusively to the treatment of heroic poetry. The epic agrees with tragedy in dealing with illustrious men and illustrious actions. Like tragedy it must have a single action, but it differs from tragedy in not having the time of the action limited or determined. While unity of action is essential to the epic, and is indeed what distinguishes it from narrative poems that are not really epics, the Renaissance conceived of vastness of design and largeness of detail as necessary to the grandiose character of the epic poem.[216] Thus Muzio says:-- "Il poema sovrano e una pittura De l' universo, e pero in se comprende Ogni stilo, ogni forma, ogni ritratto." Trissino regards _versi sciolti_ as the proper metre for an heroic poem, since the stanzaic form impedes the continuity of the narrative. In this point he finds fault with Boccaccio, Boiardo, and Ariosto, whose romantic poems, moreover, he does not regard as epics, because they do not obey Aristotle's inviolable law of the single action. He also finds fault with the romantic poets for describing the improbable, since Aristotle expressly prefers an impossible probability to an improbable possibility. Minturno's definition of epic poetry is merely a modification or paraphrase of Aristotle's definition of tragedy. Epic poetry is an imitation of a grave and noble deed, perfect, complete, and of proper magnitude, with embellished language, but without music or dancing; at times simply narrating and at other times introducing persons in words and actions; in order that, through pity and fear of the things imitated, such passions may be purged from the mind with both pleasure and profit.[217] Here Minturno, like Giraldi Cintio, ascribes to epic poetry the same purgation of pity and fear effected by tragedy. Epic poetry he rates above tragedy, since the epic poet, more than any other, arouses that admiration of great heroes which it is the peculiar function of the poet to excite, and therefore attains the end of poetry more completely than any other poet. This, however, is true only in the highest form of narrative poetry; for Minturno distinguishes three classes of narrative poets, the lowest, or _bucolici_, the mediocre, or _epici_, who have nothing beyond verse, and the highest, or _heroici_, who imitate the life of a single hero in noble verse.[218] Minturno insists fundamentally on the unity of the epic action; and directly against Aristotle's statement, as we have seen, he restricts the duration of the action to one year. The license and prolixity of the _romanzi_ led the defenders of the classical epic to this extreme of rigid circumspection. According to Scaliger, the epic, which is the norm by which all other poems may be judged and the chief of all poems, describes _heroum genus_, _vita_, gesta_.[219] This is the Horatian