Psychology is what non-Christians fall back on to explain human feelings and behavior. Otherwise you can get all you need to know straight from the Bible.
However, social scientists like to think they can make generalizations about human behavior through research which they then call facts. For example, cognitive psychologists like commie George Lakoff say that how we interpret the world is done so through conceptual frameworks.
Indeed, he interprets the broadcasts of heros such as Rush Limbaugh and Bill O'Reilly in terms of the metaphors they use within the conceptual frameworks that the Republican Party has crafted over decades. This includes truthy metaphors such as the strong father (Jesus), freedom (the right to declare pre-emptive war) and family values (the attack on homosexuals).
By constantly repeating these metaphors (what psychologists call "frequency effects") are patriots able to have all real Americans feel the truthiness of this carefully crafted reality with their guts.