Hobbes on the laws of nature Notes for October 3

Main points

Today’s class was devoted to Hobbes’s ethics. We talked about the status of Hobbes’s laws of nature, the plausibility of some of his initial definitions, and his famous reply to the Fool in ch. 15.

The right of nature and laws of nature

The biggest mystery about the right of nature and laws of nature is where they come from. Hobbes starts ch. 14 with a series of definitions. But how are we supposed to assess them? They’re just asserted without defense of elaboration.

I said that he was operating with geometry as a model. The definitions at the beginning of ch. 14 are like the definitions in Euclid’s geometry.** By the way, Oliver Byrne’s 1847 edition is quite amazing. They’re supposed to be axioms, self-evident propositions, from which theorems, namely, the laws of nature, can be derived.

I raised a few questions about whether Hobbes’s definitions really are self-evident. In particular, he seems to equate the right to use violence in self-defense with the right to use violence out of necessity. That’s the difference between repelling someone who is attacking you and attacking an innocent party, as in a pre-emptive attack or an attack on a third party that undermines an enemy (by depriving the enemy of food, say, or by taking the third party as a hostage). The right of self-defense is a lot closer to a self-evident axiom than the right to use violence out of necessity: most people accept the one but reject the other.

In Hobbes’s defense, I noted that rights of necessity were recognized in his time: the fact that one is starving is a valid excuse for stealing bread. Hobbes implicitly extended this doctrine of necessity to physical security. There’s a lot to be said for that. But he really should have said it.

Contracts and the Fool

The second law of nature tells us that we have to surrender the right to all things in order to enjoy peace. As I explained it, the point is to eliminate the upper-right and lower-right boxes of the prisoner’s dilemma. If we each give up the right to engage in sneak attacks, attacking will no longer be a dominant strategy. Instead, we will face a choice between the second best outcome (mutual peace) and the third best (mutual war). Second best is better than third, so that’s where we would stay if we could really eliminate the other options through surrendering our rights.

Of course, the difficult part is the move from “A promises not to attack B” to “B genuinely feels safe and so won’t feel the need to strike A first.” Hobbes claimed that is very difficult to achieve in the state of nature. That, in turn, explains why we need to have the state: it provides the assurance necessary for everyone to remain in the lower-right box.

In ch. 15, Hobbes addresses a question very much like Glaucon’s. The Fool asks: “if I could get away with injustice, why shouldn’t I do it?” Hobbes answered that injustice is a bad bet. Others wouldn’t be willing to participate in defensive confederacies with those who break their word and people in the state of nature need help in staying alive. Jared’s right: Hobbes changed the question. The Fool asked what he should do if he could get away with it. Hobbes said he wouldn’t get away with it.

There are two further things to note about this.

First, it means that at least small groups can establish some kind of trust among their members. There have to be defensive confederacies for the Fool to get kicked out of, after all. Nathan is right to say that the military nature of the defensive confederacies poses a problem. The relevant covenant is “I’ll defend you against attack if you defend me.” But fulfilling that covenant means putting your life at risk and Hobbes pretty clearly said all such covenants are invalid. He has some brief remarks on soldiers in ch. 21, but, as you’ll see, they don’t solve the problem. So his answer to the Fool presumes the existence of a kind of group in the state of nature. This kind of group clearly does exist in these sorts of circumstances: Hobbes correctly noted this in ch. 17. But Hobbes lacked the theoretical resources to explain how those groups could exist and some of his arguments strongly suggest that they could not.

Second, it is important that Hobbes’s answer to the Fool has holes. Suppose he had shown that it is always supremely rational for people to perform their covenants, even in the state of nature. Then people in the state of nature could make valid agreements among themselves to give up the right to attack one another and they could count on the fact that others are rational to keep them in the lower-right box. That would undercut Hobbes’s case for the state because it would show that it’s possible for people to live peacefully amongst themselves without a state.

Key terms

These terms and ideas should be familiar after today’s class.

  1. Right
  2. Covenant
  3. The Fool
  4. Why it would be a bad thing for Hobbes if it always made sense for people to keep their covenants in the state of nature.


I’ll start on Monday with the problem in the third part of the handout. I think I can explain why those three points are consistent. But I have to confess that the passage in the last section resists my efforts.

This page was written by Michael Green for Social & Political Philosophy, Philosophy 33, Fall 2012. It was posted October 3, 2012.
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