Editing Scientific theory (section)

==Formation==
[[File:RobertHookeMicrographia1665.jpg|thumb|left|upright=0.60|The first observation of [[Cell (biology)|cells]], by [[Robert Hooke]], using an early [[microscope]].<ref>Hooke, Robert (1635–1703). [http://digicoll.library.wisc.edu/cgi-bin/HistSciTech/HistSciTech-idx?id=HistSciTech.HookeMicro ''Micrographia''], Observation XVIII.</ref> This led to the development of [[cell theory]].]]
The [[scientific method]] involves the proposal and testing of [[hypothesis|hypotheses]], by deriving [[predictions]] from the hypotheses about the results of future experiments, then performing those experiments to see whether the predictions are valid. This provides evidence either for or against the hypothesis. When enough experimental results have been gathered in a particular area of inquiry, scientists may propose an explanatory framework that accounts for as many of these as possible. This explanation is also tested, and if it fulfills the necessary criteria (see above), then the explanation becomes a theory. This can take many years, as it can be difficult or complicated to gather sufficient evidence.{{citation needed|date=March 2023}}
Once all of the criteria have been met, it will be widely accepted by scientists (see [[scientific consensus]]) as the best available explanation of at least some phenomena. It will have made predictions of phenomena that previous theories could not explain or could not predict accurately, and it will have many repeated bouts of testing. The strength of the evidence is evaluated by the scientific community, and the most important experiments will have been replicated by multiple independent groups.{{citation needed|date=March 2023}}

Theories do not have to be perfectly accurate to be scientifically useful. For example, the predictions made by [[classical mechanics]] are known to be inaccurate in the relativistic realm, but they are almost exactly correct at the comparatively low velocities of common human experience.<ref name = "Misner1973">Misner, Charles W.; Thorne, Kip S.; Wheeler, John Archibald (1973). ''Gravitation,'' p. 1049. New York: W. H. Freeman and Company. {{ISBN|0-7167-0344-0}}.</ref> In [[chemistry]], there are many [[acid-base theories]] providing highly divergent explanations of the underlying nature of acidic and basic compounds, but they are very useful for predicting their chemical behavior.<ref>See [[Arrhenius-Ostwald|Acid–base reaction]].</ref> Like all knowledge in science, no theory can ever be completely [[certainty|certain]], since it is possible that future experiments might conflict with the theory's predictions.<ref name=Project2061>{{cite web|url=http://www.project2061.org/publications/sfaa/online/chap1.htm|title=Chapter 1: The Nature of Science|website=www.project2061.org}}</ref> However, theories supported by the scientific consensus have the highest level of certainty of any scientific knowledge; for example, that all objects are subject to [[gravity]] or that life on Earth [[Evolution|evolved]] from a [[Last universal ancestor|common ancestor]].<ref>See, for example, [[Common descent]] and [[Evidence for common descent]].</ref>

Acceptance of a theory does not require that all of its major predictions be tested if it is already supported by sufficient evidence. For example, certain tests may be unfeasible or technically difficult. As a result, theories may make predictions that have not yet been confirmed or proven incorrect; in this case, the predicted results may be described informally with the term "theoretical". These predictions can be tested at a later time, and if they are incorrect, this may lead to the revision or rejection of the theory. As [[Richard Feynman]] puts it:<blockquote>It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong.<ref>{{Citation |title=Feynman: It doesn't matter how beautiful your theory is, it doesn't matter how smart you are.. |url=https://www.youtube.com/watch?v=p2xhb-SdK0g |access-date=2023-03-16 |language=en}}</ref></blockquote>