I had dinner with Kahneman once a few months ago, and have now been dipping into his deep and thoughtful book Thinking, Fast and Slow.

Though I haven’t read all of it, I begin to realize that though he and I both sometimes use the word intuition, we are talking about different qualities.

For Kahneman, I think, intuition is fast thinking, snap judgements,  attractive because they avoid hard rational thinking of the second kind. As a result, it’s riddled with biases and mistakes which are interesting to psychologists.

But I once was a physicist and I’m still interested in the mysteries of nature, and so I use the word intuition in another sense. I like to think I’ve had a few occasional intuitions that were correct in small ways about small things while doing research, so I’m talking from experience. When they were right, they were the result of long hard exhausting preliminary rational struggles, banging one’s mind against the object of one’s attention. Then, finally, once in a few years, came an insight or idea or intuition, after all the struggle, that still had to elaborated by further rational effort. That’s what I call intuition.

Kahneman’s and mine are both legitimate uses of the word, but different ones.