Theory

A theory is a set of sentences which is closed under logical implication. That is, given any subset of sentences ${s_1,s_2,...}$ in the theory, if sentence is a logical consequence of ${s_1,s_2,...}$ , then must also be in the theory.

See also

Logic, Sentence

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References

Enderton, H. B. Elements of Set Theory. New York: Academic Press, 1977.

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Cite this as:

Weisstein, Eric W. "Theory." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Theory.html

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