Some of Paul Krugman’s best posts are on scientific method, specifically, how do you judge a theory. One of his posts today is beautiful, or, more correctly, would have been beautiful had he dropped the last line. In that line, he attacks people who disagree with him politically. I’ll quote, though, from the good part:

[James] Hutton was, for a time, a farmer — and in that occupation, observing the process of erosion and the laying down of deposits of various materials, he realized that the landscape he saw around him could be explained by the same forces operating over immense periods of time, as long as you posited that there were other forces uplifting ancient sediments to form today’s geological features. How could he know whether this theory was right? He made predictions; in particular, that in places you would find “angular uncomformities”, striated bodies of sedimentary rocks from different eras that were tilted relative to each other.


Why do I like this story so much? I think because it’s science of a kind everyone should be able to understand; it doesn’t rely on exotic instruments or hard math (not that there’s anything wrong with either of these), it just relies on keen observation and an open mind.

Unlike many people who comment on this blog, I do not hate Paul Krugman. I don’t even dislike him. I could psychologize here about what I think drives Paul Krugman, but I think the ground rules for this blog push me not to.

But one positive thing that I think drives him, and it’s apparent in the post I’m discussing, is a genuine interest and curiosity. The problem is that when he is so vitriolic at people he disagrees with, it’s harder for him to run with that curiosity. The reason: every once in a while he will find that the views of someone he attacked for having those views are correct. Then he’s in a bind: to admit that would mean he would have to disown some of his attacks. Ceteris paribus, it’s harder to back down when you’ve been nasty.

I remember, when I was 18 and was a fan of Ayn Rand (I still am, but much more critically), Ellen Moore, a woman who headed the local Objectivist group in Winnipeg (they weren’t supposed to call themselves “Objectivists,” but “students of Objectivism”) came by the University of Winnipeg and ran into my friend and mentor, Clancy Smith. Clancy invited Ellen to sit with him and the friend he was with. Ellen sat down and said hi. Clancy then introduced her to his friend and told her that his friend was a socialist. Well!

Ellen then asked him, prosecutor style, “Do you think the government has a right to take people’s property?” “I’d never thought about it exactly that way, but, I guess, yes,” answered the young man.

With that, Ellen got up and said, “I must leave. To sit here further and be polite would be to sanction your anti-life thoughts.” (I’m recalling as best I can from the story Clancy told me 44 years ago, but it was something like that.)

Then she left. About a minute later, she returned, looking kind of sheepish. She explained that she had forgotten her gloves.

BTW, note what site Krugman links to in mentioning David Hume’s contributions to economics.