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