self-evident

In epistemology (theory of knowledge), a self-evident proposition is a proposition that is known to be true by understanding its meaning without proof, and/or by ordinary human reason.

Some epistemologists deny that any proposition can be self-evident. For most others, one's belief that oneself is conscious and possesses free will are offered as examples of self-evidence. However, one's belief that someone else is conscious or has free will are not epistemically self-evident.

The following proposition is often said to be self-evident: "A finite whole is greater than, or equal to, any of its parts".

A logical argument for a self-evident conclusion would demonstrate only an ignorance of the purpose of persuasively arguing for the conclusion based on one or more premises that differ from it (see ' and begging the question).

Analytic propositions

It is sometimes said that a self-evident proposition is one whose denial is self-contradictory. It is also sometimes said that an analytic proposition is one whose denial is self-contradictory. But the concepts mean different things, i.e., an analytic proposition is not always a self-evident proposition.

Provided that one understands and believes a self-evident proposition, self-evident propositions are not in need of proof. Likewise, that their denial is self-contradictory does not need to be proven. It is in this sense that the self-contradictions at work in self-evident and analytic propositions are different.

Not all analytic propositions are self-evident, and it is sometimes claimed that not all self-evident propositions are analytic: e.g. my knowledge that I am conscious.

Other uses

Informal speech

In informal speech, ''self-evident'' often merely means ''obvious'', but the epistemological definition is stricter.

Moral propositions

Moral propositions may also be regarded as self-evident, although the is–ought problem described by David Hume considers that there is no coherent way to transition from a positive statement to a normative one.

For example, Alexander Hamilton cited the following moral propositions as self-evident in the Federalist No. 23:
* ''The means ought to be proportioned to the end.''
* ''Every power ought to be commensurate with its object.''
* ''There ought to be no limitation of a power destined to effect a purpose which is itself incapable of limitation.''

A famous claim of the self-evidence of a moral truth is in the United States Declaration of Independence, which states, "We hold these Truths to be ''self-evident'', that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness."; philosophically, these propositions' self-evidence is debatable.

Mathematics

In mathematics, ''self-evident'' refers to statements that need no proof. Sometimes axioms are described as self-evident. Other statements are self-evident because the statement is a proof for itself..

See also

*
* Axiom
* Contradiction
* Foundationalism
* Introspection
* Law of identity
* Primitive notion
* Self-reference
* Self-refuting idea
* infinite regress

Notes

{{Reflist

Sources of knowledge
Evidence
A priori
Fallacies
Barriers to critical thinking

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