I was listening to a podcast the other day (It’s called Dan Carlin’s Hardcore History, and if you have any interest at all in human nature or war history, I would highly recommend it). At the beginning of the very first episode I listened to, he asked the question “What would you die for?” 
As this is a fairly typical question, echoed in other forms as ‘until you know what you would die for, you’re not really living’ and so on, it is something that I’ve thought about in since I was a teen...