Optimal thought and optimal fitness through reason, logic, science, passion, and wisdom.
Feynman: How To Explain and To Not Explain
Feynman: How To Explain and To Not Explain

Feynman: How To Explain and To Not Explain

First, an introduction to the article I will excerpt: “In 1964 the eminent physicist Richard Feynman served on the State of California’s Curriculum Commission and saw how the Commission chose math textbooks for use in California’s public schools. In his acerbic memoir of that experience, titled ‘Judging Books by Their Covers,’ Feynman analyzed the Commission’s idiotic method of evaluating books, and he described some of the tactics employed by schoolbook salesmen who wanted the Commission to adopt their shoddy products. ‘Judging Books by Their Covers” appeared as a chapter in “Surely You’re Joking, Mr. Feynman!’ — Feynman’s autobiographical book that was published in 1985 by W.W. Norton & Company.”

And now an informative, interesting excerpt from Feynman’s “Judging Books by Their Covers.

“It was a pretty big job, and I worked all the time at it down in the basement. My wife says that during this period it was like living over a volcano. It would be quiet for a while, but then all of a sudden, ‘BLLLLLOOOOOOWWWWW!!!!’ — there would be a big explosion from the ‘volcano’ below. The reason was that the books were so lousy. They were false. They were hurried. They would try to be rigorous, but they would use examples (like automobiles in the street for ‘sets’) which were almost OK, but in which there were always some subtleties. The definitions weren’t accurate. Everything was a little bit ambiguous — they weren’t smart enough to understand what was meant by ‘rigor.’ They were faking it. They were teaching something they didn’t understand, and which was, in fact, useless, at that time, for the child.

“It’s vaguely right — but already, trouble! That’s the way everything was: Everything was written by somebody who didn’t know what the hell he was talking about, so it was a little bit wrong, always! And how we are going to teach well by using books written by people who don’t quite understand what they’re talking about, I cannot understand. I don’t know why, but the books are lousy; UNIVERSALLY LOUSY!

“What finally clinched it, and made me ultimately resign, was that the following year we were going to discuss science books. I thought maybe the science would be different, so I looked at a few of them.

“The same thing happened: something would look good at first and then turn out to be horrifying. For example, there was a book that started out with four pictures: first there was a wind-up toy; then there was an automobile; then there was a boy riding a bicycle; then there was something else. And underneath each picture it said, ‘What makes it go?’

“I thought, ‘I know what it is: They’re going to talk about mechanics, how the springs work inside the toy; about chemistry, how the engine of the automobile works; and biology, about how the muscles work.’

“It was the kind of thing my father would have talked about: ‘What makes it go? Everything goes because the sun is shining.’ And then we would have fun discussing it:

‘No, the toy goes because the spring is wound up,’ I would say.
‘How did the spring get wound up?’ he would ask.
‘I wound it up.’
‘And how did you get moving?’
‘From eating.’
‘And food grows only because the sun is shining. So it’s because the sun is shining that all these things are moving.’ That would get the concept across that motion is simply the transformation of the sun’s power.

“I turned the page. The answer was, for the wind-up toy, ‘Energy makes it go.’ And for the boy on the bicycle, ‘Energy makes it go.’ For everything, ‘Energy makes
it go.’

“Now that doesn’t mean anything. Suppose it’s ‘Wakalixes.’ That’s the general principle: ‘Wakalixes makes it go.’ There’s no knowledge coming in. The child doesn’t learn anything; it’s just a word!

“What they should have done is to look at the wind-up toy, see that there are springs inside, learn about springs, learn about wheels, and never mind ‘energy.’ Later on, when the children know something about how the toy actually works, they can discuss the more general principles of energy.

“It’s also not even true that ‘energy makes it go,’ because if it stops, you could say, ‘energy makes it stop’ just as well. What they’re talking about is concentrated energy being transformed into more dilute forms, which is a very subtle aspect of energy. Energy is neither increased nor decreased in these examples; it’s just changed from one form to another. And when the things stop, the energy is changed into heat, into general chaos.

“But that’s the way all the books were: They said things that were useless, mixed-up, ambiguous, confusing, and partially incorrect. How anybody can learn science from these books, I don’t know, because it’s not science.”

The article is also available at (1) “Judging Books By Their Covers” and (2) “Judging Books By Their Covers.”


When explaining, we need to consider the cognitive level and content of our audience, and we need to build new ideas hierarchically out of prior levels from the evidence of the senses.

As Galileo said: ”I should even think that in making the celestial material alterable, I contradict the doctrine of Aristotle much less than do those people who still want to keep the sky inalterable; for I am sure that he never took its inalterability to be as certain as the fact that all human reasoning must be placed second to direct experience.” (From the Second Letter of Galileo Galilei to Mark Welser on Sunspots, p. 118 of Discoveries and Opinions of Galileo, translated by Stillman Drake, (c) 1957 by Stillman Drake, published by Doubleday Anchor Books, Doubleday & Co., Garden City, New York)

Leave a Reply

Your email address will not be published. Required fields are marked *