Richard Feynman On The Difference Between Knowing the Name of Something and Knowing Something

When it comes to better ways of learning, no scientist, let alone a Nobel laureate, gets mentioned more than the great Richard Feynman.

Feynman is the most curious and high-spirited character I’ve read about who believed that the world is much more interesting than any one discipline. Therefore he was curious about almost everything he came across.

In this short clip, Feynman articulates the difference between knowing the name of something and understanding it.

Following is the important part where I wish to draw your attention:

See that bird? It’s a brown-throated thrush, but in Germany it’s called a Halzenfugel, and in Chinese they call it a Chung Ling and even if you know all those names for it, you still know nothing about the bird. You only know something about people; what they call the bird. Now that thrush sings, and teaches its young to fly, and flies so many miles away during the summer across the country, and nobody knows how it finds its way.

The point that Feynman’s trying to make is that simply knowing the name of something doesn’t mean you understand it. In order to talk to each other, we have to have words, but we often talk in fact-deficient, obfuscating generalities to cover up our lack of understanding.

In Surely You’r Joking, Mr. Feynman, he illustrates this very problem with regards to a science book for kids.

“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.”

I hope you can understand where his frustration is coming from. There is, however, a simple way to test whether you know something or only know the name of something. It’s a popular learning method named after Feynman himself: The Feynman Technique.

If you have to test your knowledge about the concept of something, say energy, then without using the word “energy”, try to rephrase what you know about it in your own language. Without using the word “energy,” explain in simple words what makes the toy, the bicycle, and the automobile go. If you cannot, you may have learned nothing about science. Truth it, most of us have not. Most of us simply know the jargon, not the meat.

The Feynman Technique involves four steps:

  1. When you learn something, learn its concept, not just its name.
  2. Then explain it in simple words so that even a 10 year old can understand.
  3. Now, identify the gaps in your explanation. Most likely you won’t get it right the first time, and that’s OK. Go back to the source to better understand it.
  4. Next, simplify further, and try again.

You should try it. It’s actually not as simple as it sounds. As a kid, Feynman’s father gave him a problem many years ago which beautifully illustrates the technique.

He said, “Suppose some Martians were to come down to earth, and Martians never slept, but instead were perpetually active. Suppose they didn’t have this crazy phenomenon that we have, called sleep. So they ask you the question: ‘How does it feel to go to sleep? What happens when you go to sleep? Do your thoughts suddenly stop, or do they move less aanndd lleeessss rraaaaapppppiidddddllllllllyyyyyyyyyyyyyy? How does the mind actually turn off?’

We take other men’s knowledge and opinions upon trust; which is an idle and superficial learning. We must try to make them our own. Otherwise, it’s like having a belly-full meal that has been chewed but not digested, and hence cannot nourish us.

I’m a huge fan of Richard Feynman. If you are a fan as well, here’s another video where he talks about the differences of merely knowing how to reason mathematically and understanding how and why things are physically analysed in the way they are.

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