§§33--42. Part v. of Varro's exposition: the departures from the old Academico-Peripatetic school. Summary. Arist. crushed the ιδεαι of Plato, Theophrastus weakened the power of virtue (33). Strato abandoned ethics for physics, Speusippus, Xenocrates, Polemo, Crates, Crantor faithfully kept the old tradition, to which Zeno and Arcesilas, pupils of Polemo, were both disloyal (34). Zeno maintained that nothing but virtue could influence happiness, and would allow the name _good_ to nothing else (35). All other things he divided into three classes, some were in accordance with nature, some at discord with nature, and some were neutral. To the first class he assigned a positive value, and called them _preferred_ to the second a negative value and called them _rejected_, to the third no value whatever--mere verbal alterations on the old scheme (36, 37). Though the terms _right action_ and _sin_ belong only to virtue and vice, he thought there was an appropriate action (_officium_) and an inappropriate, which concerned things _preferred_ and things _rejected_ (37). He made _all_ virtue reside in the reason, and considered not the _practice_ but the mere _possession_ of virtue to be the important thing, although the possession could not but lead to the practice (38). All emotion he regarded as unnatural and immoral (38, 39). In physics he discarded the fifth element, and believed fire to be the universal substance, while he would not allow the existence of anything incorporeal (39). In dialectic he analysed sensation into two parts, an impulse from without, and a succeeding judgment of the mind, in passing which the will was entirely free (40). Sensations (_visa_) he divided into the true and the untrue; if the examination gone through by the mind proved irrefragably the truth of a sensation he called it _Knowledge_, if otherwise, _Ignorance_ (41). _Perception_, thus defined, he regarded as morally neither right nor wrong but as the sole ultimate basis of truth. Rashness in giving assent to phenomena, and all other defects in the application to them of the reason he thought could not coexist with virtue and perfect wisdom (42).