ABSTRACT

Experiments on human subjects showed that the perception of sensory pleasure can serve as a common currency to allow the trade-off among various motivations for access to behaviour. The trade-offs between various motivations would thus be accomplished by simple maximisation of pleasure. A common currency for motivations as different from one another as physiological, ludic, social, aesthetic, moral, and religious is necessary to permit competition for access to behaviour. Therefore, all motivations can be compared to one another from the amount of pleasure and displeasure they arouse. It follows that the main properties of sensory pleasure should belong also to joy. Indeed, joy and sensory pleasure share identical properties; they are contingent, transient, and they index useful behaviours.