Skeptic

Skepticism or scepticism (see spelling differences) is generally any questioning attitude or doubt towards one or more items of putative knowledge or belief. It is often directed at domains, such as morality (moral skepticism), religion (skepticism about the existence of God), or the nature of knowledge (skepticism of knowledge). Formally, skepticism as a topic occurs in the context of philosophy, particularly epistemology, although it can be applied to any topic such as politics, religion, and pseudoscience.

Philosophical skepticism is a systematic philosophy that questions the notion that absolutely certain knowledge is possible. Classical philosophical skepticism derives from the classical Greek verb, skeptomai, "to search", implying searching but not finding. Adherents of Pyrrhonism (and more recently, partially synonymous with Fallibilism), for instance, suspend judgment in investigations. Skeptics may even doubt the reliability of their own senses("... the two most influential forms of skepticism have, arguably, been the radical epistemological skepticism of the classical Pyrrhonian skeptics and the Cartesian form of radical epistemological skepticism").Religious skepticism, however, is "doubt concerning basic religious principles (such as immortality, providence, and revelation)".Scientific skepticism concerns testing beliefs for reliability, by subjecting them to investigation using the scientific method, to discover empirical evidence for them.

For ordinary usage, skepticism (US) or scepticism (UK) (Greek: 'σκέπτομαι' skeptomai, to search, to think about or look for; see also spelling differences) refers to:

For philosophy, skepticism refers more specifically to any one of several propositions. These include propositions about:

Legal skepticism (aka Legal Realism) is a part of jurisprudence. It is in essence a critique of the natural law theories and of legal positivism.

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