In ancient cultures, people would drink the blood of their slain to obtain their life. People who give blood don't get angry or violent when they see it but have a surge of anger and an urge for violence. There's some kind of deep-seated understanding within people that blood is incredibly important.
Stuntman and action designer Eric Jacobus joins EconTalk host Russ Roberts for a no-holds-barred discussion of the biological basis for violence and how to avoid the worst of it, the value of violence as spectator sport, and the vast superiority of duels to feuds--Alexander Hamilton notwithstanding.