Political Philosophy Spring 2018

Locke and Hume on Consent


Locke opens chapter 8 with a strong claim that consent is a necessary condition of two things:

  1. Political authority: the state has the right to exercise political power only over those who consent to its rule.

  2. Political obligation: people are obliged to obey the state only if they consent to do so.

But how is consent to obey the state given? We talked about Locke’s answer and Hume’s objections.

Hume’s Objections

Hume’s arguments apply to any version of consent: explicit or tacit. His point is that it is impossible for consent, however expressed, to ground obligations to obey the state. He has two arguments that have the same structure.

  1. A necessary condition on consent; a condition that an expression of consent has to meet in order to create an obligation.
  2. A reason why that condition cannot be met for consent to obey the state.
  3. Conclusion: political obligation cannot be based on consent.

Here they are, with the premises marked in the passages. These paragraphs are tricky because the first premise does not always come first in the paragraph. In fact, it sometimes comes after the second premise.

Hume’s first argument.

Should it be said, that, by living under the dominion of a prince, which one might leave, every individual has given a tacit consent to his authority, and promised him obedience; it may be answered, that (1) such an implied consent can only have place, where a man imagines, that the matter depends on his choice. But (2) where he thinks (as all mankind do who are born under established governments) that by his birth he owes allegiance to a certain prince or certain form of government; it would be absurd to infer a consent or choice, which he expressly, in this case, renounces and disclaims. (Hume [1748] 1987, 475.)

Hume’s second argument.

(2) Can we seriously say, that a poor peasant or artizan has a free choice to leave his country, when he knows no foreign language or manners, and lives from day to day, by the small wages which he acquires? (1) We may as well assert, that a man, by remaining in a vessel, freely consents to the dominion of the master; though he was carried on board while asleep, and must leap into the ocean, and perish, the moment he leaves her. (Hume [1748] 1987, 475.)

The second argument turns on an assumption that consent is valid only if the person who gives it has an alternative to doing so that is not catastrophic.

That seems quite reasonable. I don’t consent to giving my money to the mugger who gives me a choice between my money and my life. That’s why I wouldn’t do anything wrong if I managed to give the mugger the slip even after I say “OK, I’ll give you all my money, just please don’t hurt me.” Here I used words that sound like consent to give him my money, but I’m not actually obliged to do so.

However we have already encountered one case in which a valid agreement can be made by someone who does not have an alternative that is not catastrophic: an army that surrenders in a war to avoid being wiped out. That is basically what Hobbes’s social contract is.

We ended the day with another case that seems to have the same feature: a gravely injured person promises to pay a doctor to save her life. Who gave us this example? None other than David Hume!

We may draw the same conclusion concerning the origin of promises, from the force which is supposed to invalidate all contracts, and to free us from their obligation. Such a principle is a proof that promises have no natural obligation, and are mere artificial contrivances for the convenience and advantage of society. If we consider aright of the matter, force is not essentially different from any other motive of hope or fear, which may induce us to engage our word, and lay ourselves under any obligation. A man, dangerously wounded, who promises a competent sum to a surgeon to cure him, would certainly be bound to performance; though the case be not so much different from that of one who promises a sum to a robber, as to produce so great a difference in our sentiments of morality, if these sentiments were not built entirely on public interest and convenience. (Hume, A Treatise of Human Nature, Book 3, Part 2, Sect. 5, Par. 15)

What is going on here is that Hume is saying that there is no natural rule about when consent is valid or invalid. Rather, we have conventional rules that recognize consent as valid in some cases and invalid in others. What distinguishes the one from the other is the usefulness of the rule. A rule requiring people to pay doctors yields useful behavior: doctors will be willing to provide services to injured people. A rule requiring people to pay muggers would not be useful: it would encourage muggings.

There are two things to take from this. First, Hume was not being entirely consistent. It’s up to you to say which Hume got it right: the one that criticized Locke or the one that criticized, well, Hume. Second, Hume has started the ball rolling towards utilitarianism, a political and moral theory that we will encounter very soon.

In any event, the chief question is whether the relationship between citizens and the state is more like the relationship between the doctor and the patient or the relationship between the kidnapped sailor and the ship captain.

Main ideas

These are the points that should be familiar to you after today’s class.

  1. The difference between explicit and tacit consent.
  2. Hume’s arguments that consent could not be valid.
  3. The doctor case vs. the ship captain case.


Hume, David. (1748) 1987. “Of the Original Contract.” In Essays, Moral, Political, and Literary, edited by Eugene F. Miller, Revised edition, 466–87. Indianapolis: Liberty Fund.

———. (1740) 1995. A Treatise of Human Nature. Edited by Mark C. Rooks. The Complete Works and Correspondence of David Hume. Charlottesville, VA: InteLex Corporation.

Locke, John. (1680) 1995. Two Treatises of Government. Edited by Mark C. Rooks. The Philosophical Works and Selected Correspondence of John Locke. Charlottesville, VA: InteLex Corporation.