Anchor: They might not be goods or services, and exchanges might not be equal.
Entailed: Exchanges are not always equal.
Contradiction: Exchanges are always equal.
Contradiction: The man is riding a giraffe through a church.
Contradiction: There is no bigger Etruscan art collection than that of the Villa Giulia in all of Italy.
Contradiction: Nobody is holding anything.
Contradiction: person on bike