'''Gödel's completeness theorem''' was proven by [[Kurt Gödel]], which states:
'''Gödel's completeness theorem''' was proven by [[Kurt Gödel]], which states:
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Any proposition in [[mathematics]] is true only if it is "sound"; that is, if it can be proven to be true. <ref>http://www.math.uchicago.edu/~mileti/museum/complete.html</ref>
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Any proposition in [[mathematics]] is true only if it is "sound"; that is, if it can be proven to be true.<ref>http://www.math.uchicago.edu/~mileti/museum/complete.html</ref>