Another philosophical intuition that has prompted the belief in Necessitarianism has been the belief that to explain why one event occurred rather than another, one must argue that the occurring event "had to happen" given the laws of nature and antecedent conditions. In a nutshell, the belief is that laws of nature can be used to explain the occurrence of events, accidental generalizations – 'mere truths devoid of nomic force' – can not be so utilized.
Sec. 6. But though this be a state of liberty, yet it is not a state oflicence: though man in that state have an uncontroulable liberty to dispose ofhis person or possessions, yet he has not liberty to destroy himself, or somuch as any creature in his possession, but where some nobler use than its barepreservation calls for it. The state of nature has a law of nature to governit, which obliges every one: and reason, which is that law, teaches allmankind, who will but consult it, that being all equal and independent, no oneought to harm another in his life, health, liberty, or possessions: for menbeing all the workmanship of one omnipotent, and infinitely wise maker; all theservants of one sovereign master, sent into the world by his order, and abouthis business; they are his property, whose workmanship they are, made to lastduring his, not one another's pleasure: and being furnished with likefaculties, sharing all in one community of nature, there cannot be supposed anysuch subordination among us, that may authorize us to destroy one another, asif we were made for one another's uses, as the inferior ranks of creatures arefor our's. Every one, as he is bound to preserve himself, and not to quit hisstation wilfully, so by the like reason, when his own preservation comes not incompetition, ought he, as much as he can, to preserve the rest of mankind, andmay not, unless it be to do justice on an offender, take away, or impair thelife, or what tends to the preservation of the life, the liberty, health, limb,or goods of another.
Necessitarianism, on this view, then, is seen to dovetail with a certain – highly controversial – view of the nature of explanation itself, namely, that one can explain the occurrence of an event only when one is in a position to cite a generalization which is nomologically necessary. Few philosophers are now prepared to persist with this view of explanation, but many still retain the belief that there are such things as nomologically necessary truths. Regularists regard this belief as superfluous.
There are good reasons why earlier interpreters and new readers tend to think the Hobbesian agent is ultimately self-interested. Hobbes likes to make bold and even shocking claims to get his point across. "I obtained two absolutely certain postulates of human nature," he says, "one, the postulate of human greed by which each man insists upon his own private use of common property; the other, the postulate of natural reason, by which each man strives to avoid violent death" (De Cive, Epistle Dedicatory). What could be clearer? - We want all we can get, and we certainly want to avoid death. There are two problems with thinking that this is Hobbes's considered view, however. First, quite simply, it represents a false view of human nature. People do all sorts of altruistic things that go against their interests. They also do all sorts of needlessly cruel things that go against self-interest (think of the self-defeating lengths that revenge can run to). So it would be uncharitable to interpret Hobbes this way, if we can find a more plausible account in his work. Second, in any case Hobbes often relies on a more sophisticated view of human nature. He describes or even relies on motives that go beyond or against self-interest, such as pity, a sense of honor or courage, and so on. And he frequently emphasizes that we find it difficult to judge or appreciate just what our interests are anyhow. (Some also suggest that Hobbes's views on the matter shifted away from egoism after De Cive, but the point is not crucial here.)