determinism · /dɪˈtəːmɪnɪz(ə)m/The idea that all events, including human action, are the result of preceding events.
The idea that cause and effect also applies to humans.
The idea that cause and effect also applies for our minds is wholly irrelevant to all of philosophy and morality.
Many people speak as if determinism should lead to wildly different conclusions about how we judge people’s actions. The thinking is something like “Well, he had a difficult childhood, and that determined him into murdering his wife, so we can’t blame or punish him for it”.
This reasoning is no more valid than the murderer himself saying “But I was really mad at her!”. In either case, the explanation does not excuse the murder. Determinism does not invalidate millennia of moral philosophy. Murder is still wrong. Murderers should still be punished.
Even if you look at it from a purely utilitarian point of view: You want to punish immoralities, because people knowing that immoral actions get punished will be the cause for the effect of people deciding not to do immoral actions. Decisions are still made in a deterministic worldview, it’s just that those decisions are based on things.
The same is true for less severe ethical issues, such as wallowing in self-pity, shirking from your responsibilities, or inaction in the face of injustice. All those things are still bad for the same reasons they’ve always been bad. They may even be more potently unethical for a determinist, as you’re more aware of the fact that your actions will be the cause for an effect on other people, their actions, and the world. It is therefore your responsibility to be the best possible cause for the best possible effect on the world and those you care about.