types - Evaluation relation In Pierce's book : meaning of "a relation satisfies a rule if ..." -

types - Evaluation relation In Pierce's book : meaning of "a relation satisfies a rule if ..." -

pierce writes in book in def. 3.5.2 :

a rule satisfied relation if, each instance of rule, either conclusion in relation or 1 of premises not.

so means if relation ( set of term pairs, pairs denoted t->t' ) contains element true->false relation satisfies rules given in fig. 3-1 because def 3.5.2 not forbid presence of such elements in relation not instance of conclusion of rule.

so, in other words, element true->false not instance of conclusion of e-if, definition 3.5.2 not tell whether true->false can in relation satisfying rules in fig 3-1 or not. def 3.5.2 talks relation elements have form " if .... .... -> .... ", not explicitly forbid ( or ) presence of element true->false, example.

question : understanding of mine right ?

types programming-languages