Truth in first-order logic Sentences are true with respect to a model and an interpretation Model contains objects(domain elements)and relations among them Interpretation specifies referents for constant symbols → objects predicate symbols → relations function symbols functional relations An atomic sentence predicate(termj,...,tem)is true iff the objects referred to by term,...,termn are in the relation referred to by predicate Truth in first-order logic • Sentences are true with respect to a model and an interpretation • Model contains objects (domain elements) and relations among them • • Interpretation specifies referents for constant symbols → objects predicate symbols → relations function symbols → functional relations • An atomic sentence predicate(term1 ,...,termn ) is true iff the objects referred to by term1 ,...,termn are in the relation referred to by predicate