"Other evils are they that may come... Yet it is not our part to master all the tides of the world, but to do what is in us for the succor of those years wherein we are set, uprooting the evil in the fields that we know, so that those who live after may have clean earth to till. What weather they shall have is not ours to rule." -Gandalf, The Last Debate, Book V, The Return of the King (J. R. R. Tolkein)