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material equivalence

noun, Logic.
equivalence (def 4b).


[ih-kwiv-uh-luh ns or for 3, ee-kwuh-vey-luh ns] /ɪˈkwɪv ə ləns or for 3, ˌi kwəˈveɪ ləns/
noun, Also, equivalency (for defs 1, 2).
the state or fact of being equivalent; equality in value, force, significance, etc.
an instance of this; an equivalent.
Chemistry. the quality of having equal valence.
Logic, Mathematics.
  1. Also called material implication. the relation between two propositions such that the second is not false when the first is true.
  2. Also called material equivalence. the relation between two propositions such that they are either both true or both false.
  3. the relation between two propositions such that each logically implies the other.
(of a logical or mathematical relationship) reflexive, symmetrical, and transitive.
1535-45; < Middle French < Medieval Latin aequivalentia, equivalent to Latin aequivalent- equivalent + -ia -ia; see -ence
Related forms
nonequivalence, noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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British Dictionary definitions for material-equivalence


the state of being equivalent or interchangeable
(maths, logic)
  1. the relationship between two statements, each of which implies the other
  2. Also called biconditional. the binary truth-function that takes the value true when both component sentences are true or when both are false, corresponding to English if and only if. Symbol: ≡ or ↔, as in –(pq) ≡ –p ∨ –q
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Word Origin and History for material-equivalence



1540s, from French équivalence, from Medieval Latin aequivalentia, from aequivalentem (see equivalent). Related: Equivalency (1530s).

Online Etymology Dictionary, © 2010 Douglas Harper
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Encyclopedia Article for material-equivalence

material equivalence

in logic and mathematics, the formation of a proposition from two others which are linked by the phrase "if, and only if." The equivalence formed from two propositions p and q also may be defined by the statement "p is a necessary and sufficient condition for q."

Learn more about material equivalence with a free trial on
Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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