On a simple basis- gut feeling as they call it. Things feel right and wrong. Doing certain things make me feel nice, doing other things make me feel bad. Dead simple. The thought of killing is horrific.
But on a more detailed level, the golden rule. I can't do something to someone else if I know if I were in there position it would hurt me, emotionally or physically. Killing is the biggest and most obvious no-no. Are there exceptions? Yeah, definitely. But not many. Killing in self defense would make me feel guilty even! Even if the person was totally at fault for me killing them.
But on a more detailed level, the golden rule. I can't do something to someone else if I know if I were in there position it would hurt me, emotionally or physically. Killing is the biggest and most obvious no-no. Are there exceptions? Yeah, definitely. But not many. Killing in self defense would make me feel guilty even! Even if the person was totally at fault for me killing them.
