A lot of experience can be an excellent teacher. A single experience, not so much. - Annie Duke

Precision uncovers disagreement. It uncovers places where your belief is different from someone else's belief. And that's good, because you want to find out when you have something wrong. It gives you the chance to get it right. Think about it like this: Saying "2 + 2 is a small number" will help you get better at math, but it won't help you become an expert. "A small number" is technically correct, but it is much more helpful for your teacher to find out if you think the answer is 5, or 2, or 4, which are all small numbers. It's true that the less precise answer makes it harder to be wrong, but you want to find out when you have the wrong answer if you are going to get better at math.

Incorporating uncertainty into the way we think about our beliefs comes with many benefits. By expressing our level of confidence in what we believe, we are shifting our approach to how we view the world. Acknowledging uncertainty is the first step in measuring and narrowing it. Incorporating uncertainty in the way we think about what we believe creates open-mindedness, moving us closer to a more objective stance toward information that disagrees with us.

（Daniel Gilbert）出版過一本著名的書《快樂為什麼不幸福？》（Stumbling on Happiness，