u/spgrk

I often see people here say that it “feels as if we have free will.” Usually this comes from either free will skeptics or libertarians, both of whom assume that free will requires our actions to be undetermined. So what they mean is that it feels as if our choices are undetermined rather than determined.

The skeptic then says this feeling is an illusion, because in reality our actions are determined.

But this comparison with ordinary illusions seems unclear to me. Usually an illusion involves mistaking one familiar kind of thing for another familiar kind of thing. Parallel lines can look as if they converge; the Earth can look flat even though it is spherical. In those cases, we understand both appearances well enough to compare them.

But with determinism and indeterminism, what exactly is the supposed difference in experience? What would an undetermined decision feel like, as opposed to a determined one? It is not obvious to me that either has a distinctive phenomenology at all.

So I am not sure what people mean when they say that determinism conflicts with how free will “feels.”

Classical compatibilists do not agree that free will requires the categorical ability to do otherwise endorsed by libertarians, where under exactly the same prior conditions more than one outcome is genuinely possible. Instead, they understand the ability to do otherwise conditionally: the agent could have done otherwise if some condition had been different, for example if they had wanted otherwise, chosen otherwise, or believed otherwise.

The objection is usually that under determinism those conditions could not have been different. But even if the antecedent is impossible, that does not necessarily make the conditional false.

Consider the statement: “I could have flown if I had grown wings.” We agree that I could not actually have grown wings, since since humans do not grow wings. But that fact alone does not make the conditional false. I am not claiming that I grew wings, or that I could have grown wings. I am only claiming that if I had grown wings, then I could have flown.
Now, maybe the statement is still false because wings would not be enough for flight under Earth gravity and atmosphere. But that is a different objection entirely.

Likewise, the compatibilist is not claiming that under determinism the agent actually could have wanted otherwise under identical prior conditions. The claim is only that if the agent’s reasons, desires, or intentions had been different, then the action would have been different.

If they can do otherwise under exactly the same circumstances, then their actions will sometimes be arbitrary, or directly contrary to their reasons.

So the problem is how to do otherwise under the same circumstances while still engaging in purposeful behaviour.

Some solutions that I have seen libertarians propose are:

(1) limit undetermined behaviour to cases where the options are approximately equally weighted;

(2) limit undetermined behaviour to cases where the outcome is unimportant;

(3) do otherwise only if you want to.

These strategies would work, but they show that indeterminism must be confined to cases where it can do no harm, cases where it would not matter if you tossed a coin. And the last proposal is just the determinist idea of doing otherwise conditionally, not doing otherwise under the same circumstances. Some libertarians seem to exclude the agent’s mental state from “the circumstances”, which is bizarre: what circumstances could be more relevant to a decision than the agent’s mental state?