Arcesilaus
For every argument there is an equally strong one against it, so we should suspend judgement on everything – and we can still act on what seems reasonable.
Placement
Head of the Academy from about 268 BCE who turned Plato’s school to scepticism: like Socrates he argued against every position, above all against the Stoic claim that some impressions cannot be false, and recommended suspending judgement on everything.
Key ideas
- Suspension of judgement (epochē) on everything
- Critique of the Stoic cognitive impression
- Socratic argument against every view
- The reasonable (eulogon) as a guide to action
Influence
Influenced by 3
Socrates
influenced by
Arcesilaus appealed to Socrates’ avowal of knowing nothing and radicalised it: not even this can be known, so he withheld assent on everything (Cicero, Academica I.45). Cicero, Academica I.44–45; SEP “Arcesilaus”
Evidence: AI draft
Socrates › 470–399 BCE
Pyrrho of Elis
influenced by disputed
The Stoic Ariston mocked Arcesilaus as ‘Plato in front, Pyrrho behind, Diodorus in the middle’; how much his suspension of judgement owed to Pyrrho is disputed. Sextus Empiricus, Outlines of Pyrrhonism I.234; Diogenes Laertius IV.33; SEP “Arcesilaus”
Evidence: AI draft
Pyrrho of Elis › c. 360–270 BCE
Influenced 2
Carneades
influenced
Carneades took up Arcesilaus’ arguments against the Stoic criterion of truth and sharpened them against Chrysippus’ refined version; he too argued on both sides of a question. Cicero, Academica II; Sextus Empiricus, Against the Logicians I.159–189; SEP “Carneades”
Evidence: also in InPhO · InPhO
Carneades › c. 214–129 BCE
Cicero
influenced
Cicero adopted the Academic method Arcesilaus had introduced – arguing against every view and withholding firm assent – and defended it in his Academica (45 BCE). Cicero, Academica I.43–46, II; SEP “Arcesilaus”; SEP “Cicero”
Evidence: AI draft
Cicero › 106–43 BCE
Criticism
Criticized by 1
Augustine
criticised by
In Contra Academicos (386) Augustine argued against the Academic scepticism begun by Arcesilaus that the wise must know truth and that some truths are certain. Augustine, Contra Academicos III.10.23–13.29; SEP “Augustine”
Evidence: AI draft
Augustine › 354–430
Criticizes 1
Zeno of Citium
criticised
Arcesilaus denied Zeno’s ‘kataleptic’ impression, since a false impression could always look the same, and concluded that the wise should suspend assent. Cicero, Academica II.77; Sextus Empiricus, Adversus mathematicos VII.150–158; SEP “Arcesilaus”
Evidence: AI draft
Zeno of Citium › c. 334–262 BCE
Position
Arcesilaus began what later writers called the Middle or New Academy. He presented his scepticism as a return to Socrates, who claimed to know only that he knew nothing, and to the questioning Plato of the dialogues: instead of stating his own view he argued against whatever his listeners proposed, so that, as Cicero puts it, equal weight of reasons on both sides would lead them to withhold assent. His main target was the Stoic theory of knowledge of Zeno of Citium. Zeno held that there are “cognitive impressions” (phantasiai katalēptikai) which come from what is and are stamped in such a way that they could not come from what is not, and that the wise person assents only to these. Arcesilaus replied that for every true impression there could be a false one indistinguishable from it – twins, eggs, dreams, madness. If so, no impression is cognitive, and the wise person, who never holds mere opinions, must suspend judgement (epochē) on everything. To the objection that this makes action impossible he answered, according to Sextus, that one can act on what is “reasonable” (eulogon). Whether he held these views himself or only drew out consequences of Stoic premises is debated. The Stoic Ariston mocked him as “Plato in front, Pyrrho behind, Diodorus in the middle”, and how much he owed to Pyrrho is still an open question. Carneades carried his method further; Cicero wrote within this Academic tradition, and Augustine argued against it.
Life & context
Arcesilaus was born around 316/315 BCE in Pitane in Aeolis, on the coast of Asia Minor. After studying mathematics he came to Athens, where he first heard Theophrastus, Aristotle’s successor in the Lyceum, and then joined Plato’s Academy under Polemo and Crantor. Around 268–264 BCE, on the death of Crates of Athens (not the Cynic Crates of Thebes), he became head of the Academy. Diogenes Laertius (IV 28–45) describes a witty, generous teacher with a large following. He wrote nothing; his arguments are known from Cicero, Sextus Empiricus, Plutarch and Diogenes Laertius. He died around 241/240 BCE at the age of 75.
Main works
- No writings (Arcesilaus taught only orally; Diogenes Laertius mentions a few poems and letters)
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