[Viliam1234]

After reading Solzhenitsyn, I was surprised to learn that these famous words are actually taken out of context.

The full idea is something like this: There are no "purely good" people, the best we can see is part-good-part-evil, and thus improving the world requires an internal battle, but... people can actually become "purely evil", and the usual path is through ideology, when you simply decide that anything you do serves a goal that justifies the means, and then you feel free to become a cartoonish villain as long as you follow the ideology.