Hobbes, Conatus and the Prisoner's Dilemma

Hobbes, Conatus and the Prisoner's Dilemma

ABSTRACT: I want to show the importance of the notion of conatus (endeavor) for Hobbes' political philosophy. According to Hobbes, all motion of bodies consists of elementary motions he called 'endeavors.' They are motions 'made in less space and time than can be given,' and they obey the law of persistence or inertia. A body strives to preserve its state and resist the causal power of other bodies. I call this the conatus-principle. Hobbes' argument for social contract and sovereign is based essentially on this model. He proves that the natural conatus makes people (i) strive to preserve their lives and therefore to get out of the destructive state of nature; (ii) commit to mutual contracts; (iii) keep the contracts unless some external cause otherwise determines; and (iv) establish a permanent sovereign power that Hobbes calls 'an artificial eternity of life.' All this is determined by the fundamental laws of nature, essentially, by the conatus-principle. I also show that the Prisoner's Dilemma interpretation of the Hobbesian state of nature does not represent all of the essential features of Hobbes' argument.

I. Conatus and Motion

Philosophers in the 17th century made hard efforts to explain the beginning and continuation of the motion of bodies. The notion of conatus ('striving' or 'endeavoring') was commonly used in the explanations. It refers to the power with which the motion of a body begins and is kept on.

What is this power? Descartes explained it to be an active power or tendency of bodies to move, expressing the power of God. He distinguished between motion and the tendency to move, but Hobbes was anxious to argue that conatus actually is motion. In The Elements of Law he says it to be the "internal beginning of animal motion" (EL I.7.2), and in his later writings the notion of 'endeavor' refers to the beginning or first part of any kind of motion. Because motion is for Hobbes "a continual relinquishing of one place, and acquiring of another" (De Corp II.8.10), the beginning of a motion of a body must be an infinitely small change in the place of the body. Accordingly, Hobbes defines endeavor "to be motion made in less space and time than can be given; ... that is, motion made through the length of a point, and in an instant or point of time" (De Corp III.15.2).

For Hobbes, the conatus is not an inherent power of a body but is determined by the motions of other bodies.