Free will and determinism
Free will is the power to choose your own actions. Determinism says that earlier causes and the laws of nature fix everything that happens. The question is whether both can be true.
What it is
Determinism is the idea that the way things go is fixed by what came before. If you knew the exact state of the world at one moment, and the laws of nature, everything that happens afterwards would follow. Free will is the ability to control your own actions and to choose what to do. The puzzle appears when you put the two side by side: if earlier causes fix every choice, could anyone ever have done otherwise?
Most people feel they could have acted differently. Many also feel a pull toward the thought that a person is only the result of their genes, their upbringing and the moment they are in. The question is what to make of both feelings.
The main views
- Compatibilism. Free will can exist even if determinism is true. What matters is whether you act from your own reasons and wishes, without outside force. David Hume held a view like this.
- Libertarianism. Free will and determinism cannot both be true, and determinism is false. Some choices are truly open, so some people are free. This has nothing to do with the political libertarianism.
- Hard determinism. Free will and determinism cannot both be true, and determinism is true. So nobody has free will in the strong sense.
An example
Picture someone who snaps at a friend after a bad night's sleep. A determinist can point to the causes: the tiredness, the stress, how they were raised. Does that mean the person was not responsible? A compatibilist says they still acted from their own state of mind and can still be asked to apologise and do better. A hard determinist says blame in the strong sense does not apply, though we can still try to change behaviour. A libertarian says that, in the end, they could have chosen differently.
Why people still disagree
- Physics has not settled it. Whether the world is deterministic is not a question philosophy can answer alone. Some theories of physics are deterministic and some are not, and quantum theory is read in both ways.
- Responsibility is at stake. Many people think that moral responsibility needs free will. So the answer changes how we think about praise, blame and punishment.
- A question about words. Part of the disagreement is about what 'free' should mean: freedom from outside force, or freedom from all earlier causes.
Written by epchē in our own words, and checked against independent sources on 8 October 2026. The sources are listed below.
Philosophies that answer it
Where each philosophy leans on this question, from the same positions the walk uses.
Some choices are truly open
Earlier causes fix every choice
Sources we used
- Causal Determinism · Stanford Encyclopedia of Philosophy, read on 8 October 2026
- Free Will · Internet Encyclopedia of Philosophy, read on 8 October 2026