Arcesilaus

Arcesilaus of Pitane became head of Plato's Academy in Athens around 268 BCE and turned it in a skeptical direction, beginning the period known as the Middle or New Academy. He wrote nothing; his views are known from Cicero, Sextus Empiricus and Diogenes Laërtius. Taking Socrates' profession of ignorance as his model, he argued on both sides of every question and attacked the Stoic claim that some impressions are so clear they cannot be false, recommending suspension of judgement.

Key ideas

• No impression is so clear that it could not be matched by a false one, against the Stoic 'cognitive impression'.
• The wise person should therefore suspend judgement (epochē).
• Arguing on both sides of a question is the proper philosophical method.
• One can act reasonably without certainty, guided by what is reasonable (to eulogon).

Major works

• Cicero, Academica (records his arguments; he left no writings)
• Sextus Empiricus, Outlines of Pyrrhonism, Book I (records him)
• Diogenes Laërtius, Lives of Eminent Philosophers, Book IV (records him)

In the conversation

• Question What is the actual difference between Pyrrhonian and Academic sceptics? Fajar Nugroho · 4 replies