Actors perform in a normative space in which gift exchange occupies the positive pole.
Reciprocal gift exchange necessarily implies meaningful silences. This aspect of secrecy opens the way to others, implicitness, ambiguity, uncertainty, as well as to hidden negative intentions. The ideal positiveness of gift exchange may therefore sheltere a secret negativeness - playing with norms. This virtual normative reversibility is the ransom of the conventionality of norms, as well of our liberty regarding biological determinisms.