 Having sketched several versions of the Relief Theory, we can note that today almost no scholar in philosophy or psychology explains laughter or humor as a process of releasing pent-up nervous energy. There is, of course, a connection between laughter and the expenditure of energy. Hearty laughter involves many muscle groups and several areas of the nervous system. Laughing hard gives our lungs a workout, too, as we take in far more oxygen than usual. But few contemporary scholars defend the claims of Spencer and Freud that the energy expended in laughter is the energy of feeling emotions, the energy of repressing emotions, or the energy of thinking, which have built up and require venting. 