Cornell, born 1957

Derk Pereboom

Imagine a man whose every decision was programmed by neuroscientists. He is not responsible. Now make the programming more and more like an ordinary upbringing in a deterministic world. There is no point at which responsibility switches back on.

The view

Pereboom, a philosopher at Cornell, calls his position hard incompatibilism. The free will needed for moral responsibility in the basic desert sense, the sense in which someone would deserve blame or punishment just because of what they knowingly did, is incompatible with determinism. It is also incompatible with the kind of indeterminism our best physics allows, because a chancy event in the brain gives the agent no more control. Unless we are agents who can cause events without being caused, which our science gives us no reason to believe, we lack that kind of free will.

Unlike many sceptics, Pereboom has spent much of his career on what follows, in Living Without Free Will (2001) and Free Will, Agency, and Meaning in Life (2014). He argues that losing basic desert would cost far less than people fear. Love, meaning, achievement and the protection of society all survive.

The argument

If an agent manipulated by neuroscientists is not responsible, and there is no relevant difference between him and an agent produced by ordinary determinism, then neither is responsible. After Pereboom, Living Without Free Will (2001)

Professor Plum kills Ms White for his own selfish reasons. He reasons carefully, would have acted differently had the reasons been different, and endorses his own desires. He meets every compatibilist condition. Now Pereboom tells four stories about how Plum came to be that way, each a little more ordinary than the last. Move through the cases.

Most people judge that Plum is not responsible in Case 1. Pereboom argues that there is no difference that matters between any two neighbouring cases, so the verdict carries all the way to Case 4, which is just ordinary life in a deterministic world. If we exempt Plum in Case 1, we should exempt everyone.

What would remain? Pereboom thinks we could still hold people to account in a forward-looking way: asking them to explain themselves, so that they reflect and reform. Dangerous people could still be detained, on the analogy of quarantine for a dangerous disease, but with no more harm than safety requires. Anger and resentment would give way to sorrow and resolve. Gregg Caruso has developed the quarantine model further.

Where he meets Dennett

Pereboom shares much of Dennett's practical agenda: less vengeance, more attention to what works, more humane institutions. Both reject the self-moving soul and the idea that randomness could help. Pereboom also agrees that forward-looking responsibility, holding people answerable so they can improve, is real and valuable. Dennett would say that is most of what responsibility is.

Where they part

On Case 1. Dennett denied that the cases are relevantly alike. In Case 1, another agent with his own goals is controlling Plum; that is a real threat to freedom, the kind the bugbears exploit. In Case 4, nobody is controlling Plum at all. Causes are not controllers, and a natural history is not a manipulator. So the argument works by borrowing our intuitions about puppeteers and applying them where there is no puppeteer. The disagreement also runs to desert itself. Pereboom thinks basic desert is the notion that matters, and gives it up; Dennett thought it was never needed, and that desert of a less metaphysical kind survives.

See every view compared →

Further reading

• Derk Pereboom, Free Will, Agency, and Meaning in Life (Oxford, 2014).
• Derk Pereboom, Living Without Free Will (Cambridge, 2001).
• Skepticism about moral responsibility, Stanford Encyclopedia of Philosophy.