ABSTRACT
The conflation of passion and the power of organisms to persevere in existence opened up the theoretical possibility of a truly universal science of nature, one that left no realm of activity beyond the reach of the laws of mechanics. This chapter outlines why traditional accounts of the passions could not easily be incorporated into the new mechanical philosophy. Thomas Hobbes's treatment of the passions is offered as a continuation of his physics. For Hobbes, the passions are the driving force behind all animal action, constitute whatever understanding of good and evil is possible and define the degree of happiness an animal possesses. Rene Descartes, Hobbes and Benedict de Spinoza each conceive of the passions as a manifestation of the law of inertia. In each account, the power of a thing to obtain what it needs to persist in being is measured by the power it possesses to obtain what it desires or loves or hopes for.
