As hunters, Sam and Dean kill monsters because such creatures pose a threat to the lives of innocent people. Sam and Dean are confronted with a complex array of moral issues in killing.Supernatural depicts hunters as ordinary people who know of the hidden supernatural evil that exists in the world and choose to spend their lives fighting it. Hunting, as the name suggests, involves tracking down these creatures and figuring out a way to destroy them. There are three fundamentally important (...) types of creatures in Supernatural: monsters, spirits, and demons. As hunters, Sam and Dean are motivated to kill monsters to defend innocent people from being victims of those monsters. As hunters, Sam and Dean follow typical rules of morality when dealing with people, but if they're warriors, those rules might change significantly. Warriors are bound by “Just War Theory,” which gives combatants special permissions for killing enemy combatants. (shrink)