and prejudices based on facts irrelevant to the matter in hand, I beg all students to free themselves in reading the _Academica_. II. _The Philosophical Opinions of Cicero_. In order to define with clearness the position of Cicero as a student of philosophy, it would be indispensable to enter into a detailed historical examination of the later Greek schools--the Stoic, Peripatetic, Epicurean and new Academic. These it would be necessary to know, not merely as they came from the hands of their founders, but as they existed in Cicero's age; Stoicism not as Zeno understood it, but as Posidonius and the other pupils of Panaetius propounded it; not merely the Epicureanism of Epicurus, but that of Zeno, Phaedrus, Patro, and Xeno; the doctrines taught in the Lyceum by Cratippus; the new Academicism of Philo as well as that of Arcesilas and Carneades; the medley of Academicism, Peripateticism, and Stoicism put forward by Antiochus in the name of the Old Academy. A systematic attempt to distinguish between the earlier and later forms of doctrine held by these schools is still a great desideratum. Cicero's statements concerning any particular school are generally tested by comparing them with the assertions made by ancient authorities about the earlier representatives of the school. Should any discrepancy appear, it is at once concluded that Cicero is in gross error, whereas, in all probability, he is uttering opinions which would have been recognised as genuine by those who were at the head of the school in his day. The criticism of Madvig even is not free from this error, as will be seen from my notes on several passages of the _Academica_[70]. As my space forbids me to attempt the thorough inquiry I have indicated as desirable, I can but describe in rough outline the relation in which Cicero stands to the chief schools. The two main tasks of the later Greek philosophy were, as Cicero often insists, the establishment of a criterion such as would suffice to distinguish the true from the false, and the determination of an ethical standard[71]. We have in the _Academica_ Cicero's view of the first problem: that the attainment of any infallible criterion was impossible. To go more into detail here would be to anticipate the text of the _Lucullus_ as well as my notes. Without further refinements, I may say that Cicero in this respect was in substantial agreement with the New Academic school, and in opposition to all other schools. As he himself says, the doctrine that absolute knowledge is impossible was the one Academic tenet against which all the other schools were combined[72]. In that which was most distinctively New Academic, Cicero followed the New Academy.