More generally, we humans not only do things, we explain why we do things. Individuals and organizations stand ready to give reasons why we do each of the things we do. While such explanations are often self-serving, they are usually considered the standard default in ordinary conversation, popular media, and in academia.This, if fully appreciated, is perhaps the single most audacious topic ever broached. It will require counter-intuitive thinking and openness to the potential truth of the "illogical" or "unreasonable" on roughly the same scale of something like quantum mechanics. The topics are also similar in that they are concepts we are not designed to comprehend. Consider the parallels. Nothing in the history of human experience would make spooky action at a distance or an upper bound to velocity or probabilistic existence intuitive by common sense. Similarly, through untold millennia we have developed the brain wiring that compels us towards certain forms of bias and self-delusion in social interactions. So how do you find The Truth when it requires outthinking your own brain? This stuff will make your head explode.
The most powerful insufficiently-appreciated insight I've ever learned is the one intellectual legacy I'd leave, if I could leave only one: we are often wrong about why we do things. Yes it is hardly original, and it might sound trivial, but few appreciate its full depth.
The question of why we think what we think is deeply pervasive; it's not just for big questions. Case in point, I recently had a discussion with a friend who was considering buying her daughter her first car. We discussed the propriety of it and how to decide on the right model, etc. My friend was zeroed in a new car, a safe and fuel efficient one. I blanched at the idea of buying a new car for a college sophomore. To paraphrase Louis CK, at that age all they have done is slurp things up for nearly two decades -- they slurp up food and money and clothes and ipods and done absolutely nothing in return except be snotty and disaffected. Now you want to let her slurp up a new car? At that age they should only be driving clap out piles of junk that cost less than the required insurance.
I suspect a majority of folks would have the same reaction. But why? What is the reason I feel so negatively about it. I could go on about the potential for spoilage, the need to teach self-sufficiency, and to reinforce the appreciation of benefits, and blah, blah, blah. But strictly considered, I have no objective basis for any of those opinions. I have never seen a rigorous scientific study of the effect on future development of buying a new car for a nineteen-year-old, nor have I seen some kind of regression analysis relating first car purchase price to long term happiness. Where do I get these opinions?
There are a number of angles to take on answering that question. (The answer "culture" is really a non-answer. A) Where did culture get those beliefs? and B) there is a body of scientific evidence to that strongly indicates many of our biases transcend culture.) One possible twist on it is that I am trying to send a signal about what sort of person I am. In the guise of reasoned analysis, I am really just shouting to the world of my frugality and sense of fairness. As Ed Harris (playing John Glenn) described himself in The Right Stuff, I'm "a lonely beacon of restraint and self-sacrifice in a squall of car-crazies." If true, this would also make me thoroughly insufferable.
Robin might point out that the hunter-gatherer societies of my ancestors had strong norms to suppress any notions of elitism and individuality and I might be tapped into those tendencies, as opposed to agricultural-industrial societies that value symbols of status.
Whatever the case, you can see this tiny, almost insignificant conversation is rife with unknowns. Imagine what happens when big issues come into play. We are constitutionally designed to have powerful and visceral reactions when our most cherished beliefs are called into question. Rationality and reason are going to be the first casualties, making further discussion self-defeating. On his blog Robin has addressed such things as the value of charity, the purpose of schools, the efficacy of medical treatment -- in all these cases, you may feel compelled to rethink what you think about why you are in favor of them, that is, if you can get past the primal indignation.
Of course, you can get all Meta with this. What's the real reason anyone is interested in real reasons? But that's pointlessly glib. The larger question is, given we actually develop a significant body of information in this arena, what do we do with it? Do we, out of devotion to The Truth, try to fight our programming when it seems irrational, or do we shrug and fatalistically trundle on as designed, under the assumption that evolution has already identified the best path? I have no idea. But whatever we do, I'm pretty sure it ends with my head exploding.