law of identity

Definition of law of identity

: one of three principles in logic:
1 : a statement (as “a house is a house”) in which the subject and predicate are the same is true
2 : the copula in an identity affirms an existent of which the identity is true
3 : a statement of an identity is the expression of an abstract relation of identity symbolized by a term (as A in “A is A”) that apparently refers in its separate instances to the subject and predicate respectively

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“Law of identity.” Dictionary, Merriam-Webster, Accessed 14 Aug. 2020.

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