Being Rational vs. Being Right: What the Difference Is
Bruce is a quiet soul who loves numbers and has great attention to detail. He wears glasses, excelled in mathematics, and is introverted. His favorite book is East of Eden. He has two cats.
Question: Is Bruce more likely a librarian or a farmer?
Research shows more people answer he’s a librarian, given the description of Bruce and how this better fits the (stereotypical) personality type.1 However, the inference is hasty because it fails to consider other relevant information. For example: What is the ratio of librarians to farmers in the population?
In other words, while what one would expect personality-wise from a farmers vs. a librarian is a consideration, it is not the only consideration. If we know there is a 20x higher likelihood than any given person is going to be a farmer than a libertarian, this fact must also be taken into account.
To borrow an example from 3Blue1Brown (who is borrowing from Daniel Kahneman), imagine a representative sample of 200 farmers and 10 librarians. Now suppose you think 40% of librarians are likely to match the description of Bruce, whereas only 10% of farmers are. In other words, from your sample, you would expect 4 librarians and 20 farmers to be “Bruce-like”. Run the math [4/(4+20)], and the probability that any random person who fits this description is a librarian is only 16.7%.
As 3B1B explains, the point is that even if you think that a librarian is 4x as likely to be “Bruce-like” than a farmer, that’s not enough to overcome the fact that there are just way more farmers — a fact that must be taken into account because it is highly relevant.
Takeaway: Rationality is not just about knowing facts but knowing which facts are relevant (and to what degree). Obviously, most people probably don’t know, nor should they be expected to know, exactly what the ratio between farmers and librarians is in the general population. However, it is probably not unfair to assume that most people have some broad understanding (or intuition) that there are far more farmers than librarians, and the question is to see whether people think to consider this fact when asked about Bruce’s occupation.
Also, notice this. You would be rational — given everything just considered — to assume Bruce is (probably) a famer, though it may still be contingently the case that Bruce is, in fact, a librarian. Conversely, you may assume — perhaps irrationally, given everything we’ve discussed — that Bruce is a librarian, but still be right!
Hence, there is a difference between being rational and being right.
There is an important consequence to this. It means a person can be rational even in being wrong. How so? Because they could be (through no fault of their own) missing information — that is, working with incomplete (or possibly faulty) data — but given the information they have, they could be making the most of it.
As Kenny Pearce reminds us, “Rationality isn’t a matter of being right all the time; it’s a matter of doing the best you can with what you’ve got. For comparison, even the best poker player will sometimes lose if she’s dealt a series of bad hands. Being an excellent poker play is about doing the best you can with the cards you’re dealt. Rationality is like that as well.”2
The upshot of seeing rationality this way is people can be charitable toward those they disagree with. They don’t have to hold that just because a person is (in their estimation) incorrect that they are irrational. Perhaps they are missing information, have been fed faulty information, etc.
For example, though I spent many years irreligious, I don’t think I was irrational in doing so — or at least not entirely, anyway. For the most part, I seemed to either be missing information (I was unacquainted with natural theology, for example) or fed misinformation since most of the religious perspectives I was familiar with were caricatures — perspectives I would continue to reject if they were the only options. All of which is to say I could have been being rational in rejecting religion even if I was (ultimately, as I now believe) incorrect. To give a charitable read on my former self3, I could say I was making good use of the hand I was dealt at the time, and later being dealt a different hand — that is, being introduced to new information — I was able to reevaluate. So, while I must admit at some point or other — either then or now — to being wrong, I don’t have to admit — either then or now — to being irrational.
This is why when trying to persuade people we seek to introduce facts, information, perspectives, etc, we consider relevant, and that could tip the scales. The atheist says belief in God is because of some hyperactive agency detection device produced by evolution for the purpose of survival. The theist counters that evolution is contingent upon physical fine tuning (= a relevant fact, which is best if only explainable by God) and that agency detection, even occasionally hyperactive, is not even a good undercutting, let alone, rebutting defeater, in light of the total evidence. Or so the conversation typically goes.
All this is to say we should not only to seek the do the best we can with the hand we’ve got but to get the best possible hand — i.e., to do the best with the best. This means not just studying logic but seeking the most reliable and relevant information, so we aren’t working with a less than stellar deck. One of the ways to ensure this is done is to understand why somebody of a differing perspective believes what they do, and genuinely trying to see through their particular paradigm.4
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For popularized version, see https://amzn.to/3v4lAI0
Is There a God? Pg. 88.
Somebody’s gotta do it.
That conservatives and moderates do a better job of this than liberals is evidenced by the research of Jonathan Haidt. For example, pg. 334 in The Righteous Mind.