Thursday, March 18, 2010

Of names and what they mean

During my train commute this week, I read James Gleick's superb
biography of the theoretical physicist Richard Feynman. When Feynman
was a child, he and his father used to go walking in the Catskill
Mountains in New York State. Here's a story Feynman told once about
this:

"The next Monday, when the fathers were all back at work, we kids were
playing in a field. One kid says to me, 'See that bird? What kind of
bird is that?'

I said, 'I haven't the slightest idea what kind of a bird it is.' He
says, 'It's a brown-throated thrush. Your father doesn't teach you
anything!'

But it was the opposite. He had already taught me: 'See that bird?' he
says. 'It's a Spencer's warbler.' (I knew he didn't know the real
name.) 'Well, in Italian, it's a Chutto Lapittida. In Portuguese, it's
a Bom da Peida. In Chinese, it's a Chung- long-tah, and in Japanese,
it's a Katano Tekeda. You can know the name of that bird in all the
languages of the world, but when you're finished, you'll know
absolutely nothing whatever about the bird. You'll only know about
humans in different places, and what they call the bird. So let's look
at the bird and see what it's doing—that's what counts.' (I learned
very early the difference between knowing the name of something and
knowing something.)"

After Feynman won the Nobel Prize for Physics and had his own children
he began to think again about the elements of teaching and about the
lessons his own father had taught. By the time his son Carl was four,
Feynman was actively lobbying against a first-grade science book
proposed for California schools. It began with picture of a mechanical
wind-up dog, a real dog, and a motorcycle, and for each the same
question: "What makes it move?" The proposed answer – "Energy makes it
move" – enraged him.

That was a tautology, he argued – an empty definition. Feynman, having
made a career of understanding the deep abstractions of energy, said
it would be better to begin a science course by taking apart a toy
dog, revealing the cleverness of the gears and ratchets. To tell a
first-grader that "energy makes it move" would be no more helpful, he
said, than saying "God makes it move" or "moveability makes it move."
He proposed a simple text for whether one is teaching ideas or mere
definitions:

"You say, 'Without using the new word which you have just learned, try
to rephrase what you have learned in your own language. Without using
the word energy, tell me what you know now about he dog's motion.' "

See James Gleick, Genius: Richard Feynman and Modern Physics, Abacus,
1992, pp. 28-29 and 398.