I am afraid I missed completely logical connection between sacrificing and optimism.

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offtop: Why do usually someone want to say an aphorism in foreign language? Normally it is a good idea when that language fits that aphorism best, that is when it is a native phrase for that language and keeps its spirit. So, here is an advice: if you want a good phrase in Russian, find it in Russian sources, not translate.

Russian is absolutely not the best language for the straightforward moralizing, BTW.