|What keeps our inner beast at bay?|
More than likely it is a combination of the two that maintains order and stability in group settings. It's an inherent desire for structure, order and a sense of belonging to a group maintained through external mandates of socially acceptable behavior. Then again, it could just be a genetically rooted selfishness to always seek what benefits individuals the most. In my opinion, the majority of people aren't good or evil. They are primarily pragmatic, doing what needs to be done in order to create the best conditions for living.
The reason civilized society works pretty well isn't that we are all running around in love with one another and wanting the best for everyone. It's because we do well individually in well-ordered and structured groups. If we were beings based solely on an inherent love for our fellow humankind, there would only be an us paradigm and not an us-versus-them dynamic that usually dominates social groupings. Groups aren't identified solely by their own unique characteristics, but also by whom the group opposes. We are as much identified by what we are as by what we are not. This tendency for a group to create an "other" to position themselves against helps to strengthen the internal structure and order of the group. Everyone moving in the same direction creates a formidable forward momentum, and in that solidification of the group, each member receives individual benefits.
People keep their "beasties" in check because generally being a beast has limited advantages. Everyone knows that one jerk who acts badly on a consistent basis and in turn has a pretty crappy life. His lack of control keeps him from creating situations in which he excels or succeeds. Our baser, uglier aspects of our nature usually reveal themselves only when the benefits outweigh the disadvantages. We don't go around randomly acting like asses because we would never get anywhere. Sometimes people let the "inner beastie" out when the group assents to allowing beastly behavior to exist, especially if the bad behavior in some way creates an advantage for the group. It's one of the things that allows for mob mentality that occasionally ends in horrific events like genocide. Because the savagery is directed towards the "other" and not towards anyone within the group, people will indulge in their ugliness because it doesn't create damage for individuals within the group.
Sometimes people just lose their sense of control and our beastie rears its ugly head only to quickly retreat in the face of social pressure and consequence. Thank God for that. Having laws, ethics and morals as a society creates circumstances in which people will do good for society as a whole. It shouldn't matter that this goodness is rooted in an inherently selfish motivation. The good acts in and of themselves have validity regardless of their origin. We may not be all saint nor all beast. We may, in fact, be neither. But, as long as the end result is a society in which good behavior prevails, then our pragmatic natures are working as intended and society at large benefits. It would be seriously spiffy if we strengthened this pragmatic goodness and had fewer incidents of beastly group behaviors. As a whole, humankind needs to focus on and create more opportunities for individual benefits through group behavior in order to make this happen.
In the fantasy world I like to regularly inhabit, people are mostly good just for goodness' sake. Evil people are an aberration and our "inner beasties" are mild and fairly benign. Intellectually I understand how people and groups behave and interact with one another and why they do what they do, but my "inner saint" wants to believe otherwise. I'm all for unicorns, rainbows, glitter and an inherent, selfless love for humankind. However, as I type this, I am still looking for how this particular fantasy benefits me as I know it somehow does, thus proving my point we are all selfish bastards at heart.