Here is one way to change your mind. Think through something carefully, relying on strong connections. You may at some point walk right into a conclusion that contradicts a previous opinion. At this point something will give. The strength of this method is that it is strengthened by the very attachment to your ideas that it undermines. The more stubborn you are, the harder you push against your own stubbornness.
When I first read the words above—on August 1st, 2003, at around 3 o’clock in the afternoon—it changed the way I thought. I realized that once I could guess what my answer would be—once I could assign a higher probability to deciding one way than other—then I had, in all probability, already decided. We change our minds less often than we think. And most of the time we become able to guess what our answer will be within half a second of hearing the question.
How swiftly that unnoticed moment passes, when we can’t yet guess what our answer will be; the tiny window of opportunity for intelligence to act. In questions of choice, as in questions of fact.
The principle of the bottom line is that only the actual causes of your beliefs determine your effectiveness as a rationalist. Once your belief is fixed, no amount of argument will alter the truth-value; once your decision is fixed, no amount of argument will alter the consequences.
You might think that you could arrive at a belief, or a decision, by non-rational means, and then try to justify it, and if you found you couldn’t justify it, reject it.
But we change our minds less often—much less often—than we think.
I’m sure that you can think of at least one occasion in your life when you’ve changed your mind. We all can. How about all the occasions in your life when you didn’t change your mind? Are they as available, in your heuristic estimate of your competence?
Between hindsight bias, fake causality, positive bias, anchoring/priming, et cetera, et cetera, and above all the dreaded confirmation bias, once an idea gets into your head, it’s probably going to stay there.
1Dale Griffin and Amos Tversky, “The Weighing of Evidence and the Determinants of Confidence,” Cognitive Psychology 24, no. 3 (1992): 411–435.