Certainty

The term in everyday speech usually refers certainty the subjective certainty regarding certain held for well- justified beliefs, for example, can refer to natural or moral issues do.

In various sciences is " certainty " also used in a narrower, more precise or partly differing importance. So is held certainty for one of the criteria for knowledge, for example in the philosophical theory of knowledge by some theorists. Many debates in this regard are closely related to the problem of skepticism. In addition, it is discussed which elements play the role for the occurrence of subjective certainty, including some " evidence" of reliability "expert opinions ", external circumstances such as the frequency of the arguments put forward or inner modalities such as emotional stability.

Furthermore, this expression is certainty or security application, inter alia, in different approaches to the theory of practical rationality, the argumentation theory, decision theory, different sub- areas of modern logic, information theory and automata theory, economics, and psychology.

Distinct from "knowledge" and "truth"

When the terms " knowledge" and " certainty " can be distinguished, then mostly so that knowledge refers to the knowledge of existing theories, events or facts and may be true or false, complete or incomplete.

Certainty on the other hand refers to the conviction of a person, that knowledge is true or can be derived so that the truth may be accepted without problems. Certainty is therefore not property of the facts or judgments, but the result of a mental process and the subject -dependent. A full statement can not be then: "The verdict is certainly U ", but " The judgment U is certainly for the subject S."

This distinction but there are also various paradoxes that " be true " on the difference between " holding something to be true " and or the general problem of what is meant by "truth" based. In this case, as the held true also objectively be considered true, although the reasons for the personal conviction are wrong.

This occurs at Gettiers problem. Gettier investigated, what are the reasons for certainty and notes that each base can be deceiving.

Because different according to this definition, certainty and truth and certainty is not a criterion of truth, certainty is quite problematic at about witnesses. They report what they have seen and are aware of its certainly; nevertheless it may be wrong. Vice versa, there are the certainty that something can not be, although all the facts speak for it.

Philosophical considerations of certainty

Some theorists, Plato was the first to distinguish levels of certainty from mere opinion the way to firm conviction. These terms are, however, not uniformly used.

Subject of constant philosophical conflicts is the question of whether there can be certain knowledge. Early on was this recognized that any chain of evidence should if they do not run infinitely or lead to circular reasoning (see also of infinite regress ), sometime of statements ( axioms ) must assume that are not justifiable, so declared manifestly true need. Whether there are such statements and that should be it, is highly controversial.

For example, Immanuel Kant held the categorical imperative for an absolutely certain ethical standard; other philosophers deny this vehemently. The question of whether such principles as other than " justify " with a logical proof can be discussed again and again. Intuitionism asserts, some truths are clear from the intuition and obviously true. Realism refers to the ( direct ) evidence, that is, basic truths such as the principle of contradiction, which are not only irrefutable and unprovable, but out of itself evident. Dialectical materialism sees in the practice at any given time is a reason for (relative) certainty. The critical rationalism rejects certainty from at all, but knows tentatively accepted as true knowledge and is quite different degrees of verisimilitude, even if it can not derive any certainty. Representatives of perspectivism claim that there are no truths, only different points of view; perceived certainty can be set while subjective, but prove anything. Finally, some philosophers go so far, not only the existence of "obvious" true propositions, but also the validity of the rules of inference to doubt. Then, however, any discussion would be practically meaningless.

A major study of the early 20th century wrote the Austrian philosopher Ludwig Wittgenstein with his work On Certainty.

Security in the mathematical sense ( stochastics, statistics, logic, computer science )

In addition to the meanings given above, the term security in the stochastics and statistics is used to denote the absolute ( 100 percent ) probability of applying a statement or the occurrence of an announced event. In this meaning, security is with English. certainty translate.

In this sense, the term has also found its way into the vernacular (eg: this I can " certainly " or " definitely not " say).

In theoretical computer science and logic you speak of safety, if the total correctness of a program or the correctness of a statement could be formally proven.