Nihilism

[Amarok]

Hard determinism doesn't necessarily lead to fatalism, but it does logically lead to nihilism (at least the way I understand it). However, if like me, you adhere to the Many Worlds interpretation of quantum mechanics, you are obliged to accepted that fatalism (at least to some degree) is logical. It means there is nothing you can do to 100% prevent any possible future from occurring. You might be in a world where a terrible future awaits you (we don't know for sure), and (if so) there is nothing you can do about it. Hell, even with other interpretations of quantum mechanics (Copenhagen), this can be the case as well, as futures are probabilistically determined rather than 100% determined by antecedents. The cosmos is perhaps more disturbing than is commonly thought.

That said, I do agree it is important to find healthy psychological means to cope with the implications of such views, but without having to delude ourselves. My way of coping with this is simply to just go with the flow and don't dwell on worst case scenarios that are unlikely to occur in this universe. Also, just because all metaphysical possibilities may be actualized does not mean we know with 100% certainty what are all metaphysical possibilities. It may be the fact, that given who I am, there are scary/disturbing futures that may never happen to me because they would be metaphysically impossible (impossible under certain contexts). Perhaps my doppelgangers (with exact genetics and experiences up till their equivalent of my current moment) will never in one universe be as heinous as, say, Hitler because the way I'm conditioned would absolutely never lead to that kind of outcome. I hope so.

I borrowed this line of thinking from Pereboom:
IMO hard incompatibilism does not necessarily lead to nihilism. Considering ethics, it compels us against "moral anger." Inasmuch as moral anger is misplaced when directed toward one who is not morally responsible, the actions that follow from moral anger are themselves unethical. Moral anger assumes that such and such agent freely chose to commit certain actions, and therefore should be treated accordingly. I wouldn't consider it counter to moral thinking that a much better approach would be to consider what caused a person to commit such an action, and (rather than concentration on punishment) use that energy to work on society. Find out what is causing people to make certain choices and focus on that. As a moral objectivist, I feel right at home with my incompatibilist metaphysics. 

Hopefully that demonstrates (in principle) how determinism/incompatibilism do not necessarily lead to nihilism--at least as far as ethics is concerned.

Lol. I wouldn't spend too much time worrying if your evil twin becomes Hitler. Just ask yourself two questions:

1. Am I the one with the goatee?
2. If so, is it well-trimmed?

Agreed in terms of crime and moral action we would need to deal with environmental factors etc . I also point out that behaviors even in determinism can be modified .