The Feynman Technique: The Best Way to Learn Anything

 

If you’re after a way to supercharge your learning and become smarter, The Feynman Technique might just be the best way to learn absolutely anything.

Let’s explore the method Nobel prize-winning physicist Richard Feynman used to ensure he understood anything he studied better than anyone else.

There are four steps to the Feynman Learning Technique:

1. Choose a concept you want to learn about
2. Pretend you are teaching it to a student in grade 6
3. Identify gaps in your explanation;  Go back to the source material, to better understand it.
4. Review and simplify (optional)

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If you’re not learning, you’re standing still. But how do we get feedback on what we’re learning? And how do we go about learning new subjects and identifying gaps in our existing knowledge?

Two Types of Knowledge

Feynman understood the difference between knowing something and knowing the name of something, and it’s one of the most important reasons for his success. Most of us focus on the wrong type of knowledge. The first type of knowledge focuses on knowing the name of something — what it’s called. The second focuses on actually knowing something — that is understanding something.

“The person who says he knows what he thinks but cannot express it usually does not know what he thinks.”

— Mortimer Adler

The Feynman Technique

Step 1: Teach it to a child

Take out a blank sheet of paper. At the top write the subject you want to learn. Now write out everything you know about the subject you want to understand as if you were teaching it to a child. Not your smart adult friend, but rather a 12-year-old who has just enough vocabulary and attention span to understand basic concepts and relationships.

It turns out that one of the ways we trick ourselves is that we use complicated vocabulary and jargon and it masks our lack of understanding.

When you write out an idea from start to finish in simple language that a child can understand, you force yourself to understand the concept at a deeper level and simplify relationships and connections between ideas.

Some of this will be easy. These are the places where you have a clear understanding of the subject. At other points, you will struggle. These are the points where you have some gaps in your understanding.

Step 2: Review

Only when you encounter gaps in your knowledge—where you forget something important, are not able to explain it, or simply have trouble thinking of how variables interact—can you really start learning.

Now that you know where you got stuck, go back to the source material and re-learn it until you can explain it in basic terms. Only when you can explain your understanding without jargon and in simple terms can you demonstrate your understanding. This is the work required to learn, and skipping it leads to the illusion of knowledge.

Identifying the boundaries of your understanding also limits the mistakes you’re liable to make and increases your chance of success when applying knowledge.

Step 3: Organize and Simplify

Now you have a set of hand-crafted notes. Review them to make sure you didn’t mistakenly borrow any of the jargon from the source material. Organize them into a simple narrative that you can tell. Read it out loud. If the explanation isn’t simple or sounds confusing, that’s a good indication that your understanding in that area still needs some work.

If you follow this approach over and over, you will end up with a binder full of pages on different subjects. If you take some time twice a year to go through this binder, you will find just how much you retain.

Step 4 (Optional): Transmit

If you really want to be sure of your understanding, run it past someone (ideally who knows little of the subject –or find that 12-year-old!). The ultimate test of your knowledge is your capacity to convey it to another.

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Not only is the Feynman Technique a wonderful recipe for learning, but it’s also a window into a different way of thinking that allows you to tear ideas apart and reconstruct them from the ground up.

When you’re having a conversation with someone and they start using words or relationships that you don’t understand, ask them to explain it to you like you’re 12.

Not only will you supercharge your own learning, but you’ll also supercharge theirs. Importantly, approaching problems in this way allows you to understand when others don’t know what they are talking about. (See Batesian Mimicry)

Feynman’s approach intuitively believes that intelligence is a process of growth, which dovetails nicely with the work of Carol Dweck, who beautifully describes the difference between a fixed and growth mindset.

The Difference Between Knowing the Name of Something and Knowing Something

Richard Feynman (1918-1988) was no ordinary genius. He believed that “the world is much more interesting than any one discipline.”

His explanations — on why questions, why trains stay on the tracks as they go around a curve, how we look for new laws of science, how rubber bands work, — are simple and powerful.

Even his love letters will move you. His love letter to his wife sixteen months after her death will stir any heart.

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

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.

Knowing the name of something doesn’t mean you understand it. We talk in fact-deficient, obfuscating generalities to cover up our lack of understanding.

How then should we go about learning? On this Feynman echoes Einstein, and proposes that we take things apart:

In order to talk to each other, we have to have words, and that’s all right. It’s a good idea to try to see the difference, and it’s a good idea to know when we are teaching the tools of science, such as words, and when we are teaching science itself.

[…]

There is a first grade science book which, in the first lesson of the first grade, begins in an unfortunate manner to teach science, because it starts off with the wrong idea of what science is. There is a picture of a dog–a windable toy dog–and a hand comes to the winder, and then the dog is able to move. Under the last picture, it says “What makes it move?” Later on, there is a picture of a real dog and the question, “What makes it move?” Then there is a picture of a motorbike and the question, “What makes it move?” and so on.

I thought at first they were getting ready to tell what science was going to be about–physics, biology, chemistry–but that wasn’t it. The answer was in the teacher’s edition of the book: the answer I was trying to learn is that “energy makes it move.”

Now, energy is a very subtle concept. It is very, very difficult to get right. What I mean is that it is not easy to understand energy well enough to use it right, so that you can deduce something correctly using the energy idea–it is beyond the first grade. It would be equally well to say that “God makes it move,” or “spirit makes it move,” or “movability makes it move.” (In fact, one could equally well say “energy makes it stop.”)

Look at it this way: that’s only the definition of energy; it should be reversed. We might say when something can move that it has energy in it, but not what makes it move is energy. This is a very subtle difference. It’s the same with this inertia proposition.

Perhaps I can make the difference a little clearer this way: If you ask a child what makes the toy dog move, you should think about what an ordinary human being would answer. The answer is that you wound up the spring; it tries to unwind and pushes the gear around.

What a good way to begin a science course! Take apart the toy; see how it works. See the cleverness of the gears; see the ratchets. Learn something about the toy, the way the toy is put together, the ingenuity of people devising the ratchets and other things. That’s good. The question is fine. The answer is a little unfortunate, because what they were trying to do is teach a definition of what is energy. But nothing whatever is learned.

[…]

I think for lesson number one, to learn a mystic formula for answering questions is very bad.

There is a way to test whether you understand the idea or only know the definition. It’s called the Feynman Technique, and it looks like this:

Test it this way: you say, “Without using the new word which you have just learned, try to rephrase what you have just learned in your own language.” Without using the word “energy,” tell me what you know now about the dog’s motion.” You cannot. So you learned nothing about science. That may be all right. You may not want to learn something about science right away. You have to learn definitions. But for the very first lesson, is that not possibly destructive?

I think this is what Montaigne was hinting at in his Essays when he wrote:

We take other men’s knowledge and opinions upon trust; which is an idle and superficial learning. We must make them our own. We are just like a man who, needing fire, went to a neighbor’s house to fetch it, and finding a very good one there, sat down to warm himself without remembering to carry any back home. What good does it do us to have our belly full of meat if it is not digested, if it is not transformed into us, if it does not nourish and support us?

 https://fs.blog/

Here his unique technique to learn new materials: Step 1. Choose a topic you want to understand and start studying it. Once you know what it is about, take a piece of paper and write the topic at the top of the page. Step 2. Pretend you’re teaching the idea to someone else. Write out an explanation on paper while you describe them out loud. Like this, you get an idea of what you understand and where you still have gaps. Whenever you get stuck, go back and study. Repeat that process until you can explain it. Step 3. Finally, do it again, but now simplify your language or use an analogy to make the point. If your explanation ends up wordy and confusing, that’s an indication that you do not understand the idea well enough. If that happens, go back until you have mastered it. It is the process of thinking about an idea while teaching it that makes the method so effective. Once you can explain an idea with simple language and create graphic analogies, you have deeply understood it and will remember it for a long time.