Do you think you would you risk your life to save a stranger? Would it make a difference if it were an elderly person or a child? What about a neighbor's dog or cat?
Depends on how risky the situation is and whether or not I can determine if my intervening is going to really make a difference. For instance if I saw an old lady getting her butt whoop by five big strong guys I'm not going to run up to them and try to fight them off. That's just stupid! LOL On the other hand if I saw somebody trapped, say in a car that's on fire, I might try to help them escape before they get blown up.