Philosophical skepticismPhilosophical skepticism (UK spelling: scepticism; from Greek σκέψις skepsis, "inquiry") is a family of philosophical views that question the possibility of knowledge. It differs from other forms of skepticism in that it even rejects very plausible knowledge claims that belong to basic common sense. Philosophical skeptics are often classified into two general categories: Those who deny all possibility of knowledge, and those who advocate for the suspension of judgment due to the inadequacy of evidence.
Hellenistic philosophyHellenistic philosophy is Ancient Greek philosophy corresponding to the Hellenistic period in Ancient Greece, from the death of Alexander the Great in 323 BC to the Battle of Actium in 31 BC. The dominant schools of this period were the Stoics, the Epicureans and the Skeptics. The preceding classical period in Ancient Greek philosophy had centered around Socrates (c. 470–399 BC), whose students Antisthenes, Aristippus, and Plato went on to found Cynicism, Cyrenaicism, and Platonism, respectively.
Western philosophyWestern philosophy encompasses the philosophical thought and work of the Western world. Historically, the term refers to the philosophical thinking of Western culture, beginning with the ancient Greek philosophy of the pre-Socratics. The word philosophy itself originated from the Ancient Greek (φιλοσοφία), literally, "the love of wisdom" φιλεῖν , "to love" and σοφία sophía, "wisdom").
PyrrhonismPyrrhonism is an Ancient Greek school of philosophical skepticism which rejects dogma and advocates the suspension of judgement over the truth of all beliefs. It was founded by Aenesidemus in the first century BCE, and said to have been inspired by the teachings of Pyrrho and Timon of Phlius in the fourth century BCE. Pyrrhonism is best known today through the surviving works of Sextus Empiricus, writing in the late second century or early third century CE.
EpochéIn Hellenistic philosophy, Epoché (ἐποχή epokhē, "cessation") is suspension of judgment but also as "withholding of assent". Pyrrhonism Epoché plays an important role in Pyrrhonism, the skeptical philosophy named after Pyrrho, who is regarded as the founder of ancient skepticism. The Pyrrhonists developed the concept of "epoché" to describe the state where all judgments about non-evident matters are suspended to induce a state of ataraxia (freedom from worry and anxiety).
PyrrhoPyrrho of Elis (ˈpɪroʊ; Pyrrhо̄n ho Ēleios; 360-270 BC), born in Elis, Greece, was a Greek philosopher of Classical antiquity, credited as being the first Greek skeptic philosopher and founder of Pyrrhonism. Pyrrho of Elis is estimated to have lived from around 365/360 until 275/270 BCE. Pyrrho was from Elis, on the Ionian Sea. He was likely a member of the Klytidiai, a clan of seers in Elis who interpreted the oracles of the Temple of Zeus at Olympia where Pyrrho served as a high priest.
ArcesilausArcesilaus (ˌɑːrsɛsɪˈleɪ.əs; Ἀρκεσίλαος; 316/5–241/0 BC) was a Greek Hellenistic philosopher. He was the founder of Academic Skepticism and what is variously called the Second or Middle or New Academy – the phase of the Platonic Academy in which it embraced philosophical skepticism. Arcesilaus succeeded Crates of Athens as the sixth scholarch of the Academy around 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.
Agrippa the SkepticAgrippa (Ἀγρίππας) was a Pyrrhonist philosopher who probably lived towards the end of the 1st century CE. He is regarded as the author of "The Five Tropes (or Modes, in τρόποι) of Agrippa", which are purported to establish the necessity of suspending judgment (epoché). Agrippa's arguments form the basis of the Agrippan trilemma. Sextus Empiricus described these "modes" or "tropes" in Outlines of Pyrrhonism, attributing them "to the more recent skeptics"; Diogenes Laërtius attributes them to Agrippa.
Academic skepticismAcademic skepticism refers to the skeptical period of the Academy dating from around 266 BCE, when Arcesilaus became scholarch, until around 90 BCE, when Antiochus of Ascalon rejected skepticism, although individual philosophers, such as Favorinus and his teacher Plutarch, continued to defend skepticism after this date. Unlike the existing school of skepticism, the Pyrrhonists, they maintained that knowledge of things is impossible. Ideas or notions are never true; nevertheless, there are degrees of plausibility, and hence degrees of belief, which allow one to act.
CarneadesCarneades (kɑrˈniːədiːz; Καρνεάδης, Karneadēs, "of Carnea"; 214/3–129/8 BC) was a Greek philosopher and perhaps the most prominent head of the Skeptical Academy in ancient Greece. He was born in Cyrene. By the year 159 BC, he had begun to attack many previous dogmatic doctrines, especially Stoicism and even the Epicureans whom previous skeptics had spared. As scholarch (leader) of the Academy, he was one of three philosophers sent to Rome in 155 BC where his lectures on the uncertainty of justice caused consternation among leading politicians.
