The prevailing view is that the human condition is an immensely complex concept, impossible to characterize, and yet, by considering our evolutionary upbringing, a very simple internal conflict can be proposed that explains much of what we see in the world around us.  A similar analysis also reveals the rather depressing reason why happiness seems so hard to find.

Although nothing is certain, the simplicity of these views, combined with their explanatory power, suggest that they are what we should believe.