  As for poetry, Philodemus thinks that, while there is no natural criterion of good verse, there are ‘conceptions’ (ennoiai, here, apparently the same as prolêpseis) of good and bad verse, which allow a universal judgment (koinê krisis) of poetry based on criteria which exist, whether or not one recognizes them. Such poetry does not require detailed analyses or rules, attention to which spoils one’s ability to judge according to the common conceptions, so treatises on poetry should concentrate on giving general principles which allow the expression of the preconceptions of the good poem (Poem. 5, xxx.25–33 Mangoni). For poetry the aims should be to imitate the diction which also teaches useful things and to have a content which is between what wise and vulgar people would say (Poem. 5, xxv.30–xxvi.20, cf. Janko 2000: 131 and n. 1). After all, the sage will rather express what is crucially useful for life in philosophical prose, while poetry will be a pleasant adjunct or pastime. This will apply to both writing and reading, neither of which should require much study or effort, if it is not to be destructive of the philosophical life.