Editing Self-evidence

{{Short description|Epistemologically probative proposition}}
{{more citations needed|date=December 2023}}

In [[epistemology]] (theory of knowledge), a '''self-evident proposition''' is a proposition that is known to be true by understanding its meaning without [[Logical argument|proof]],{{Citation needed|reason=Reliable source needed for the whole sentence|date=August 2014}} 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 [[consciousness|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 ''{{Lang|la|[[ignoratio elenchi]]}}'' 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–synthetic distinction|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. {{explain|date=October 2015}}

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 deity|Creator]] with certain [[Inalienable rights|unalienable Rights]], that among these are [[Life, liberty and the pursuit of happiness|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 [[axiom]]s are described as self-evident.<ref>{{Cite web |last=Maddy |first=Penelope |date=1988 |title=Believing the Axioms |url=https://math.berkeley.edu/~kpmann/Axioms.pdf |website=Journal of Symbolic Logic}}</ref> Other statements are self-evident because the statement is a proof for itself.{{Citation needed|date=October 2023}}.

== See also ==
{{Wiktionary|self-evidence}}
* {{slink|1=2 + 2 = 5|2=Self-evident truth and self-evident falsehood}}
* [[Axiom]]
* [[Contradiction]]
* [[Foundationalism]]
* [[Introspection]]
* [[Law of identity]]
* [[Primitive notion]]
* [[Self-reference]]
* [[Self-refuting idea]]
* [[infinite regress]]

==Notes==
{{Reflist}}

[[Category:Sources of knowledge]]
[[Category:Evidence]]
[[Category:A priori]]
[[Category:Fallacies]]
[[Category:Barriers to critical thinking]]<!-- is it actually self-evident to both parties of an argument? -->

[[de:Evidenz]]