Only to survive, nobody has to know what you must do. There's been a sweep of debate over certain events in history where people were stranded for days - weeks, they eventually turned to cannibalism by eating those who have died, it's not something you would WANT to do but in order to survive, sometimes you must do what you wouldn't normally in order to survive. Same thing when you're starving to death where even a lump of moldy, smelly cheese will look very appetizing. We're living in comfort where we don't have to take in consideration of the sort but we must understand that some actions will need to be taken if we hope to survive in certain situations.