You’re Probably Wrong: The Real Reason Why Humans “Reason”

1468 words – approximately a 7-minute read.

Definitely the safest place to practice my chainsaw juggling.

Simply put, your brain is not well designed for finding the truth. And, until you accept this and why it is so, you will fail to understand why good-natured, intelligent people can’t seem to agree on the belief systems like religion and politics. But, at the cost of accuracy, we may actually be getting something much more powerful. This post talks about the real origin and main brain function of human reasoning, and why our social inability to settle on certain ‘facts’ is a persistent feature of being human. Hopefully, those predictably infuriating dinner table debates will make much more sense.

The Engine of your Thoughts

Our capacity for thinking is awesome. In fact, it’s so awesome that we can sit here and actually ponder how awesome it is. A pillar of your cognition is your ability to reason through stuff to come to a conclusion about it. It’s both the awareness of that conclusion as well as a rationale that justifies why it is so. How sophisticated!

What you and most of us believe about the purpose of our reasoning powers is that it improves our knowledge about the world (accuracy) and make better decisions (enlightened actions). It’s not. Most of us are wrong; and, mountains of research in psychology and neuroscience suggest that this is false.

The main function of Reason is not to enhance individual cognition through delivering accuracy. In fact, it is often designed to distort accuracy for other purposes.

That’s absurd, right?

So Many Problems: A Broken Brain?

In case you’re not intimately aware, basically all humans have significant systematic biases in the way they search for and interpret certain information. Those biases are always there, running on autopilot, skewing the information we get from our environment. Those crafty little biases chronically lead to epistemic distortions, and oftentimes, pretty crummy decisions.

Here’s a few major cognitive biases you harbor:

  • Confirmation bias. You are much more likely to accept information that reinforces your belief about something, and much more likely to reject information that calls that belief into question.
  • Motivated reasoning. Not only your reception of evidence, but also your search for evidence about some conclusion is guided by your interest to support your position and oppose the contrary one.
  • Belief entrenchment. By merely thinking about an issue, your current attitude will become more entrenched. You don’t consider so much as you defend. The more you reason the more entrenched you get. Does this sound anything like the last facebook debate you were in? Even when you and your counterpoint are exposed to the same new info, your attitudes will likely actually polarize further! Simply watch this play out with the US gun control debate after our next mass shooting, and then punch yourself in the neck in frustration.

There’s a bunch more. Here’s a pretty big list. Face it. The way your brain handles info seems built to screw up in certain ways.

Weird. Your search for info is biased. Your propensity to change positions is biased. Your ability to handle abstract logical tasks suck. You stink at reasoning about relative probabilities too. It’s not just you; it’s all of us.

Oh, you’re educated, you say? Intelligent? Good for you, Professor Ego: Evidence shows that you are at least as much if not more affected by these biases. In fact, you’re better at making justifications than the rest of us, independent of accuracy. And, if you have more knowledge on a subject, your reliance on your biases are even easier to observe.

It looks like we are built to easily and readily make justifications for emotionally satisfying judgments and actions. While most people seem to consciously desire an accurate view of the world, our brains construct a coherent worldview at the expense of accuracy.

WTF? Is this all a big design blunder?

The Real Function of Reasoning

Children watching monsoon cloud formation
“Look! The moon has an Arby’s!”

We’re not broken. Well, okay, maybe you are, but that’s beside the point. For the rest of us, our brains are operating on something even more important than finding an accurate view of reality. We are busy being great at arguing.

The function of reasoning is not epistemic. It’s to be persuasive, and to be resistant to the persuasion of others. There’s a compelling theory now championed by anthropologists Mercier and Sperber that argues that “Reasoning” is a suite of inferential processes oriented to convince others and to adopt compelling beliefs in order to flourish in collaborative communities. Yes, learning accurate facts happen, but more as a side effect of gathering the best information to help us argue better. To persuade, convince.

A Tad More In-Depth

Our juicy little minds consist of elaborate computational mechanisms honed under natural selection to improve relative fitness. Given that selection operates just as much on our social environment as our natural one, a set of social cognitive mechanisms have evolved and persisted to contribute to our relative fitness in that (extremely complex) environment as well.

When you can establish a bigger and more loyal coalition of friends and allies than others, you can manipulate the social environment in a way more conducive to your vision. If you’re really good at it, that environment becomes more calibrated to your wants and expectations, and you will reap much more from it than your in-group rivals can. And, the more intuitive and automatic arguing is for you, the less you’d have to toil over how to apply it.

My deeper point is this: Strategic social manipulation is actually a more important selection factor than even having an accurate view of the world. In our highly consequential social environment, your relative ability to convince others in your cohort is, in a sense, engineering reality itself. You are manipulating the very orientation and assumptions of the social system itself.

In essence, your deft powers of reason don’t actually adjust your beliefs to better reflect reality, they adjust social reality to better reflect your beliefs. If you’re the best at making arguments and evaluating the flaws of others, you become the main designer in what it means to be accurate. Powerful indeed.

You and the Group Both Benefit

Argumentation serves the group too. While the deft, charismatic individual could typically reap the most individual benefits, it empowers and orients the group, relative to rival groups. Reasoning as persuasion among a group enables coalitions of individuals to communicate and settle into one collaborative agenda. It makes human communication more deliberate, effective and advantageous. It shouldn’t be too surprising then that in general, women are found to be most attracted to males who demonstrate social dominance; in the long span of human prehistory, it has long entailed higher prospects of success than muscles, beauty, general intelligence, or even wealth.

The “Defects” Make Sense

When Reason is seen in this light, suddenly all those pesky cognitive biases make sense. It also explains why human logical performance is crummy until it is applied in a social context involving dialogue. It all seems to purposely fit together. And, it makes sense that always be maximally convincing and maximally accurate; sometimes the most accurate information may undermine our case being made to others. When caught between being accurate and being ‘right’, being right is generally much more consequential.

Human reasoning is not some deeply flawed mechanism; it is a remarkably efficient specialized system adapted to convince others of the social facts that work best for us.  It is not designed to guide us to the best choices but the ones that are easier to justify to others. As an evolved arguer, you exquisitely look for arguments that support of convenient conclusion, and favor conclusions for which some argument can be found.

So What?

Debate around the dinner table. Debate on facebook. Persuasion in the office. Or at home. It can be terribly frustrating until you acknowledge the experience for what it is.

We may not have brains designed for being epistemically accurate. But, we are designed for something even more important: gaining control over engineering our social environment better than others. As for the whole accuracy thing, it turns out that being accurate in assessments, in general, will lead to better outcomes, so occasionally accurate facts will rise to the top. And, we have developed scientific methods and instruments to help us overcome our intuition to persuade and build real knowledge.

So just remember. When you are in debates, see it for what it is not: an experience to find the truth. See it for what it is: an battle for relative control over the attitudes and beliefs of your people. May the best brains win.

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Do you love psychology, brain science, politics, war, relationships, culture, decision sciences, complex systems, networks, futurism, or philosophy in general? Whoa, me too.

My name is Bobby Valentine. This is my personal blog. It will be a resource, reflecting my current thinking on what we are, how we could know, why it matters, and how you and I fit in it all. About once per week expect a thoughtful (and occasionally reasonable) point of view on enduring questions or current events.

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