Hypothesis

{{sources needed}}{{Philosophyscience}}
{{cquote|The great tragedy of science — the slaying of a beautiful hypothesis by an ugly fact.|||[[Thomas Huxley]]<ref>[http://quoteworld.org/quotes/6985 Quote World - Thomas Henry Huxley]</ref>}}

A '''hypothesis''' is a proposed explanation for an event or observation. Hypotheses are testable statements, and are a core part of the [[scientific method]].

==Definition==
"Hypothesis" (like the word [[theory (science)|theory]]) has a few different meanings — the common usage, a more exact [[scientific]] one, and also a meaning in [[statistics]], such as [[null hypothesis]]. The meanings behind "hypothesis" are rarely confused, except when people try to abuse language for the furtherance of ideology, as in the way [[creationists]] use the words "theory" and "hypothesis" to try to delegitimize scientific ideas they do not like. Conflating these is often one of the sources of [[War on Science|confusion and criticism of science]]. 

In everyday language, a hypothesis means a possible explanation for a phenomenon. This can be an idea that is merely [[PIDOOMA]] in nature, or something that follows [[common sense]]. Often, it's considered a somewhat "weaker" form of the term "theory", as if a theory is only a hypothesis that has more support — but this isn't the case, and the distinction between hypothesis and theory is part of the scientific definitions of the two terms.

In science, the meaning is more precise. As part of the scientific method, a hypothesis is the stage where a testable statement is generated. In this case, a hypothesis is usually an original idea generated from data, or from existing theories, which is tested for its ability to explain and predict phenomena. A successful hypothesis lends support to the theory that produced it, and the successful theory will produce further hypotheses to be tested. For instance, a theory about gravitation would produce a hypothesis about the orbits of planets — the orbit of [[Mercury]] being a specific hypothesis that differentiated classical [[Newton]]ian mechanics with [[general relativity]] as a model for [[gravity]].

There are often a multiplicity of hypotheses on any subject<ref group=note>For example, the Big Bang versus [[Steady State theory|steady state]] hypotheses for the origin of the [[universe]].</ref> which are slowly (or quickly!) winnowed down to one or two similarly viable possibilities. The ability of an hypothesis to make viable [[prediction]]s is used to test its validity. The inability of one to do so tends to make it evident that [[Pseudoscience|it is not actually scientific]].

==General requirements==
While it could be said that hypotheses have no requirements in order to actually be considered hypotheses, if they are to progress through to become a theory, they must fit certain criteria (note that a [[Scientific theory]] is a fully working model, not a simple speculation). Perhaps most importantly, [[falsifiability|it should be theoretically possible to disprove them]] &mdash; that is not to say that they ''will'' be disproved, only that it must be ''possible''. Obviously, if they are actually disproved, they will not progress.

A hypothesis often gathers together or builds on earlier theories or hypotheses. This was, for example, the case with [[Darwin]]'s [[theory of evolution]] by [[natural selection]]. Although this is a normal part of the scientific process, some [[fundamentalist]]s seem to think it devalues his contributions.

Hypotheses have to be testable (which is one of the many reasons [[Goddidit]] isn't a scientific hypothesis). However, hypotheses about what happened a long time ago, like at the point of the [[Big Bang]] for example, are much more difficult to test ''directly'' (which [[Ken Ham|some people]] take to mean [[willful ignorance|it can't be tested at all]]).

==See also==
*[[Prediction]]
==Notes==
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==References==
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[[Category:Science]]
[[Category:Philosophy of science]]
[[Category:Scientific hypothesis]]

Categories: Science, Philosophy of science, Scientific hypothesis