“The world is just a word for the things you value around you, right? That’s something I’ve had since I was born. If you tell me to rule such a world, I already rule it.” – Tohsaka Rin (Fate: stay night) on not taking over the world.

I think it is having a small core of things and people you value that keeps you grounded and healthy. Our "Something to Protect" if you like. Without that investment and connection to things that matter it's easy to lose your way.