PhilosophyPhilosophy (love of wisdom in ancient Greek) is a systematic study of general and fundamental questions concerning topics like existence, reason, knowledge, values, mind, and language. It is a rational and critical inquiry that reflects on its own methods and assumptions. Historically, many of the individual sciences, like physics and psychology, formed part of philosophy. But they are considered separate academic disciplines in the modern sense of the term.
AtaraxiaIn Ancient Greek philosophy, ataraxia (Greek: ἀταραξία, from "a-", negation and tarachē "disturbance, trouble")—generally translated as "unperturbedness", "imperturbability", "equanimity", or "tranquility"—is a lucid state of robust equanimity characterized by ongoing freedom from distress and worry. In non-philosophical usage, ataraxia was the ideal mental state for soldiers entering battle. Achieving ataraxia is a common goal for Pyrrhonism, Epicureanism, and Stoicism, but the role and value of ataraxia within each philosophy varies in accordance with their philosophical theories.
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.
Problem of the criterionIn the field of epistemology, the problem of the criterion is an issue regarding the starting point of knowledge. This is a separate and more fundamental issue than the regress argument found in discussions on justification of knowledge. In Western philosophy the earliest surviving documentation of the problem of the criterion is in the works of the Pyrrhonist philosopher Sextus Empiricus. In Outlines of Pyrrhonism Sextus Empiricus demonstrated that no criterion of truth had been established, contrary to the position of dogmatists such as the Stoics and their doctrine of katalepsis.
Suspension of judgmentSuspended judgment is a cognitive process and a rational state of mind in which one withholds judgments, particularly on the drawing of moral or ethical conclusions. The opposite of suspension of judgment is premature judgement, usually shortened to prejudice. While prejudgment involves drawing a conclusion or making a judgment before having the information relevant to such a judgment, suspension of judgment involves waiting for all the facts before making a decision.
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.
Circular reasoningCircular reasoning (circulus in probando, "circle in proving"; also known as circular logic) is a logical fallacy in which the reasoner begins with what they are trying to end with. Circular reasoning is not a formal logical fallacy, but a pragmatic defect in an argument whereby the premises are just as much in need of proof or evidence as the conclusion, and as a consequence the argument fails to persuade. Other ways to express this are that there is no reason to accept the premises unless one already believes the conclusion, or that the premises provide no independent ground or evidence for the conclusion.
AenesidemusAenesidemus (Αἰνησίδημος or Αἰνεσίδημος) was a 1st-century BC Greek Pyrrhonist philosopher from Knossos who revived the doctrines of Pyrrho and introduced ten skeptical "modes" (tropai) for the suspension of judgment. He broke with the Academic Skepticism that was predominant in his time, synthesizing the teachings of Heraclitus and Timon of Phlius with philosophical skepticism. Although his primary work, the Pyrrhonian Discourses, has been lost, an outline of the work survives from the later Byzantine empire, and the description of the modes has been preserved by few ancient sources.
EpicureanismEpicureanism is a system of philosophy founded around 307 BCE based upon the teachings of Epicurus, an ancient Greek philosopher. Epicurus was an atomist and materialist, following in the steps of Democritus. His materialism led him to religious skepticism and a general attack on superstition and divine intervention. Originally a challenge to Platonism, its main opponent later became Stoicism.
Moral skepticismMoral skepticism (or moral scepticism in British English) is a class of meta-ethical theories all members of which entail that no one has any moral knowledge. Many moral skeptics also make the stronger, modal claim that moral knowledge is impossible. Moral skepticism is particularly opposed to moral realism: the view that there are knowable and objective moral truths. Some defenders of moral skepticism include Pyrrho, Aenesidemus, Sextus Empiricus, David Hume, J. L.