Certainty

Related concepts and fundamentals:Certainty is perfect knowledge that has total security from error, or the mental state of being without doubt.Ludwig Wittgenstein, On Certainty, #115 Certainty is perfect knowledge that has total security from error, or the mental state of being without doubt. Objectively defined, certainty is total continuity and validity of all foundational inquiry, to the highest degree of precision. Something is certain only if no skepticism can occur. Philosophy (at least, historical Cartesian philosophy) seeks this state. Major elements of philosophical skepticism - the idea that things cannot be known with certainty, which the ancient Greeks expressed by the word acatalepsia - are apparent in the writings of several ancient Greek philosophers, particularly Xenophanes and Democritus. The first Hellenistic school that embraced philosophical skepticism was Pyrrhonism, which was founded by Pyrrho of Elis. Pyrrho's skepticism quickly spread to Plato's Academy under Arcesilaus, who abandoned Platonic dogma and initiated Academic Skepticism, the second skeptical school of Hellenistic philosophy. The major difference between the two skeptical schools was that Pyrrhonism's aims were psychotherapeutic (i.e., to lead practitoners to the state of ataraxia - freedom from anxiety, whereas those of Academic Skepticism were about making judgments under uncertainty (i.e., to identify what arguments were most truth-like). In his Meditations on First Philosophy, Descartes first discards all belief in things which are not absolutely certain, and then tries to establish what can be known for sure. Although the phrase 'Cogito, ergo sum' is often attributed to Descartes' Meditations on First Philosophy, it is actually put forward in his Discourse on Method. Due to the implications of inferring the conclusion within the predicate, however, he changed the argument to 'I think, I exist'; this then became his first certainty. On Certainty is a series of notes made by Ludwig Wittgenstein just prior to his death. The main theme of the work is that context plays a role in epistemology. Wittgenstein asserts an anti-foundationalist message throughout the work: that every claim can be doubted but certainty is possible in a framework. 'The function serve in language is to serve as a kind of framework within which empirical propositions can make sense'. Physicist Lawrence M. Krauss suggests that the need for identifying degrees of certainty is under-appreciated in various domains, including policy making and the understanding of science. This is because different goals require different degrees of certainty—and politicians are not always aware of (or do not make it clear) how much certainty we are working with. Rudolf Carnap viewed certainty as a matter of degree ('degrees of certainty') which could be objectively measured, with degree one being certainty. Bayesian analysis derives degrees of certainty which are interpreted as a measure of subjective psychological belief. Alternatively, one might use the legal degrees of certainty. These standards of evidence ascend as follows: no credible evidence, some credible evidence, a preponderance of evidence, clear and convincing evidence, beyond reasonable doubt, and beyond any shadow of a doubt (i.e. undoubtable—recognized as an impossible standard to meet—which serves only to terminate the list). The foundational crisis of mathematics was the early 20th century's term for the search for proper foundations of mathematics.