Some people have argued that because people's choices are often influenced by factors that are not relevant to rational decision making, people do not have free will. For instance, people are much more willing to register as an organ donor on their driver's liscenses if this is presented as the default option ("check this box to be an organ donor" vs "check this box to opt out of being an organ donor"). Does a person need to be rational in order to have free will?

I'd like to suggest that it's not an all-or-none affair, but yes: rationality is part of free will. One way to think about it is to ask what kind of "free will" would be worth caring about. A will that's not able to respond to reasons is one I wouldn't want to have, and any sense in which it would be "free" seems to me to be pretty Pickwickian.

This point doesn't settle the question of how free will and determinism are related. Robert Kane's version of libertarianism, for instance, doesn't call up any obvious conflict between free will and reason. That's partly because reason doesn't always dictate a single course of action. It would be reasonable of me to work on my administrative duties for the rest of the afternoon, and also reasonable to spend the time on research. But it wouldn't be reasonable to tear off my britches and run naked into the street, and I don't think the fact that this would be beyond me (absent a very good reason) to mean I don't have free will.

So yes: little glitches in our reason do represent limitations on our "free will" (a phrase, by the way, that I think could use a holiday.) But reason needn't be perfect for us to be reasonably free.

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