I think I agree. I also think wedrifid wanted to talk about predictions of what the candidates do, even if they are not guaranteed not to change their mind.
This doesn't seem impossible, just harder. You'd have to make a guess as to how likely the candidates are to implement a different policy from the one they promised, as well as the effect the possible policies will have.
The candidates do have an incentive to signal that they are unlikely to "waffle". If you are relatively certain to implement your policies, then at least those who agree with you will predict that you'll have a good effect. If you look like you might change your mind, even your supporters might decide to take a different option, because who knows what you will do?
In theory, you might gain a bigger advantage by somehow signaling that you will change your mind for good reasons. Then if new information comes up in the future, you're a better choice than anyone who promises not to change their mind at all. But this is trickier and less convincing.
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.