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Philosophy

What is Determinism?

Determinism is the idea that every event — including human choices — is fully caused by prior events following natural laws, so nothing could happen differently than it does. It sits at the heart of the debate over whether free will is possible.

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Key things to understand

  • 1Core claim: given the past and the laws of nature, only one future is possible.
  • 2It implies your choices are the inevitable result of earlier causes, including brain states.
  • 3Causal determinism is grounded in physics; some argue quantum randomness complicates it.
  • 4It clashes with libertarian free will but can be reconciled with 'compatibilist' free will.
  • 5It raises hard questions about moral responsibility and blame.

Frequently asked questions

If determinism is true, do we have free will?
It depends on the definition. Hard determinists say no; compatibilists say you can still act freely if your actions flow from your own desires, even if those were themselves caused.
Does quantum physics disprove determinism?
Quantum mechanics introduces randomness at tiny scales, which challenges strict determinism — but randomness isn't the same as free choice, so it doesn't straightforwardly restore free will.
How does determinism affect moral responsibility?
If no one could act otherwise, traditional blame and praise become harder to justify — a major reason the free-will debate matters for ethics and justice.

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