Arcesilāus in Harpers Dictionary of Classical Antiquities
Son of Battus, king of Cyrené, who was driven from his kingdom in a sedition, and died B.C. 575. The second of this name died B.C. 550 (Herod.iv. 159).
A philosopher, born at Pitané, in Aeolis, the founder of what was termed the Middle Academy. The period of his birth is usually given as B.C. 316. Arcesilaüs at first applied himself to rhetoric, but subsequently passed to the study of philosophy, in which he had for teachers, first Theophrastus, then Crantor the Academician, and probably also Polemo (Diog. Laert. iv. 24, 29; Acad. i. 9). Besides the instructors above named, Arcesilaüs is also said to have diligently attended the lectures of the Eretrian Menedamus, the Megarian Diodorus, and the sceptic Pyrrho. His love for the quibbling of these individuals has been referred to as the source of his scepticism and his skill in refuting philosophical principles. At the same time it is on all hands admitted that of philosophers Plato was his favourite. He seems to have been sincerely of opinion that his view of things did not differ from the true spirit of the Platonic doctrine; nay, more, that it was perfectly in agreement with those older philosophical teachings, from which, according to the opinion of many, Plato had drawn his own doctrines-namely, those of Socrates, Parmenides, and Heraclitus.
Upon the death of Crantor , the school in the Academy was transferred by a certain Socratides to Arcesilaüs, who here introduced the old Socratic method of teaching in dialogues, although it was rather a corruption than an imitation of the genuine Socratic mode. Arcesilaüs does not appear to have committed his opinions to writing; at least the ancients were not acquainted with any work which could confidently be ascribed to him. Now, as his disciple Lacydes also abstained from writing, the ancients themselves appear to have derived their knowledge of his opinions only from the works of his opponents, of whom Chrysippus was the most eminent. Such a course must naturally be both defective and uncertain, and accordingly we have little that we can confidently advance with respect to his doctrines. According to these statements the results of his opinions would be a perfect scepticism, expressed in the formula that he knew nothing, not even that which Socrates had ever maintained that he knew -namely, his own ignorance (Acad. i. 12). This expression of his opinion implicitly ascribes to Arcesilaüs a full consciousness that he differed in a most important point from the doctrine of Socrates and Plato. But, as the ancients do not appear to have ascribed any such conviction to Arcesilaüs, it seems to be a more probable opinion which imputes to him a desire to restore the genuine Platonic dogma, and to purify it from all those precise and positive determinations which his successors had appended to it. Indeed, one statement expressly declares that the subject of his lecture to his most accomplished scholars was the doctrine of Plato (Cic. l. c.); and he would therefore appear to have adopted this formula with a view to meet more easily the objections of the dogmatists. Now if we thus attach Arcesilaüs to Plato, we must suppose him to have been in the same case with many others, and unable to discover in the writings of Plato any fixed and determinate principles of science. The ambiguous manner in which almost every view is therein advanced, and the results of one investigation admitted only conditionally to other inquiries, may perhaps have led him to regard the speculations of Plato in the light of mere shrewd and intelligent conjectures. Accordingly, we are told that Arcesilaüs denied the certainty not only of intellectual, but also of sensuous knowledge (Cic. De Orat. iii. 18).
Arcesilaus in Wikipedia
Arcesilaus (Greek: Ἀρκεσίλαος) (316/5-241/0 BC) was a Greek philosopher and founder of the Second or Middle Academy-the phase of Academic skepticism. Arcesilaus succeeded Crates as the sixth head (scholarch) of the Academy c. 264 BC. He did not preserve his thoughts in writing, so his opinions can only be gleaned second-hand from what is preserved by later writers. He was the first Academic to adopt a position of philosophical skepticism, that is, he doubted the ability of the senses to discover truth about the world, although he may have continued to believe in the existence of truth itself. This brought in the skeptical phase of the Academy. His chief opponents were the Stoics and their belief that reality could be comprehended with certainty.
Arcesilaus was born in Pitane in Aeolis. His early education was provided by Autolycus the mathematician, with whom he migrated to Sardis. Afterwards, he studied rhetoric in Athens; but adopted philosophy and became a disciple first of Theophrastus and afterwards of Crantor. He subsequently became intimate with Polemo and Crates, and eventually became head of the school (σχολάρχης).
Diogenes Laertius says that, like his successor Lacydes, he died of excessive drinking, but the testimony of others (e.g. Cleanthes) and his own precepts discredit the story, and he is known to have been much respected by the Athenians.
Arcesilaus committed nothing to writing, his opinions were imperfectly known to his contemporaries, and can now only be gathered from the confused statements of his opponents. This makes his philosophy difficult to evaluate and partly inconsistent. This led scholars to see his skepticism in several ways. Some see his philosophy as completely negative or destructive of all philosophical views. Others regard him as taking the position that nothing can be known on the basis of his philosophical arguments. Others claimed he held no positive views on any philosophical topic, including the possibility of knowledge.
On the one hand, he is said to have restored the doctrines of Plato in an incorrupted form; while, on the other hand, according to Cicero, he summed up his opinions in the formula, "that he knew nothing, not even his own ignorance." There are two ways of reconciling the difficulty: either we may suppose him to have thrown out such aphorisms as an exercise for his pupils, as Sextus Empiricus, who calls him a Sceptic, would have us believe; or he may have really doubted the esoteric meaning of Plato, and have supposed himself to have been stripping his works of the figments of the Dogmatists, while he was in fact taking from them all certain principles.
The Stoics were the chief opponents of Arcesilaus; he attacked their doctrine of a convincing conception (katalêptikê phantasia) as understood to be a mean between science and opinion - a mean which he asserted could not exist, and was merely the interpolation of a name. It involved a contradiction in terms, as the very idea of phantasia implied the possibility of false as well as true conceptions of the same object.
It is a question of some importance as to how the Academic skepticism of the Middle and New Academy was distinguished from that of Pyrrhonism. Admitting the formula of Arcesilaus, "that he knew nothing, not even his own ignorance," to be an exposition of his real sentiments, it was impossible in one sense that skepticism could proceed further: but the Academic skeptics do not seem to have doubted the existence of truth in itself, only our capacities for obtaining it. It differed also from the principles of the pure skeptic in the practical tendency of its doctrines: while the object of the one was the attainment of perfect equanimity, the other seems rather to have retired from the barren field of speculation to practical life, and to have acknowledged some vestiges of a moral law within, at best but a probable guide, the possession of which, however, formed the real distinction between the sage and the fool. Slight as the difference may appear between the speculative statements of the two schools, a comparison of the lives of their founders and their respective successors leads to the conclusion, that a practical moderation was the characteristic of the Academic skeptics.