The woman sweating her ass off beneath her burqa in Saudi Arabia convinces herself this is the best of all possible worlds just as the slave did, just as the man struggling to survive from paycheck to paycheck in capitalism just as the aging hippy who used to have a nagging sense of loneliness about the lack of community but now but manages to drive hours away in his car 6 to 9 times a year for festivities like going rafting or to the Burning Man festival and just focuses on that.
It's so easy. You fall asleep, you forget. The goal is to be happy. Utilize your stupidity. If someone points out how wrong it is, demonize them.
Everyone's a pangloss. Everyone ensures that this world will never change. That it will always be insane. Everyone has learned how to be happy by being insane.
It's simply evolution. He best adapts who believes this is the best of all possible worlds.
And so you have children and then, simply evolution, the person who exists for their children, for their family, for their welfare and no others, best passes on their genes. A morality that doesn't go beyond one's own children. No sense of community beyond one's own relatives. Even if, by some chance, you don't think this is the best of all possible worlds, you just turn away from everything but your family, you turn away from all else. And your children flourish and reproduce in turn.
And these people are the only people alive at all now.