Richard Feynman, a celebrated scientist and the winner of Nobel prize in Theoretical Physics, was infamous for barging into any classroom (unrelated to Physics) in his university. He would then ask questions and make his fellow professors uncomfortable.

One day Feynman decided to attend a Biology class. Being aware of Feynman’s history of mischief, the Biology professor posed a condition to discourage him. Feynman could attend the class provided he would do all the assignments and write research papers like everyone else attending that class. To the professor’s surprise, Feynman agreed.

Feynman’s first assignment required him to study the nervous system of cats. So he went to the librarian in the biology section and asked her if she could give him a map of the cat.

“A map of the cat, sir?” she asked, horrified. “You mean a zoological chart!” 

“From then on there were rumors about some dumb biology graduate student who was looking for a map of the cat.”, wrote Feynman in his book Surely You’re Joking Mr. Feynman.

Feynman wasn’t dumb. In fact, what made biology department think that way was precisely the brilliance which made Feynman a towering genius.

Amused as much you may feel on Feynman’s choice of words, there’s is no way you can misunderstand what he meant by a map of the cat. Can you?

Legend has it that Feynman once walked into the Mathematics department and challenged the experts. He claimed that if they could explain him any mathematical concepts, no matter how difficult it was, in simple terminology without using any jargons, Feynman would quickly arrive at the same conclusions which took these mathematicians years to derive using complex formulae.

And there lies the secret. The secret that made Richard Feynman a genius. His intellect was a product of gargantuan curiosity and being a perpetual learning machine. He clearly articulated in his talks that the primary roadblock to learning was the colossal confusion between knowing something (chauffeur knowledge) and knowing the name of something.

The chasm between memorizing the definition and understanding the idea is ten miles wide.

Here’s the Feynman’s test of knowledge – without using the new word which you have just learned, try to rephrase what you have just learned in your own language. Can you do that without using the jargons?

Put simply, the measure of whether we have understood something is if we’re able to successfully explain it to a five-year-old.

That’s the fundamental idea behind Feynman’s Technique for learning anything. A few months back Vishal handcrafted an excellent illustration that captures the essence of Feynman’s Technique. I include it here again –

When new knowledge is handed to you for the first time, it’s an unpolished stone. It has to be tenderly analyzed from many angles, through different means. Turning that stone of knowledge into wisdom requires careful chiseling. And one such chiseling-tool is teaching.

The core principle is that the mere act of teaching something allows a more effective integration of its learning. Explain the idea to yourself as if you’re teaching it to someone who doesn’t understand that idea at all. And as you do that, you’ll realize that our mind starts playing along and literally begins bombarding questions as if a five-year-old sitting in the corner of your head and asking stupid (but valid) questions.

Soon, you’ll get stuck or confused while explaining it to your imaginary five-year-old self. That’s when you’ll need to go back to the original source of information from where you learned it the first time. Re-learn it. Then repeat this process until you leave the shallowness of mere familiarity and enter the deep waters of intuitive understanding.

Practicing Feynman technique sounds like a lot of work. Doesn’t it? But that’s true for any crucial skill. It demands effort and it demands patience. Once you scale the initial resistance, Feynman’s technique is probably the most clever hack to learn anything deeply. Turn this trick into a habit and I guarantee that your learning abilities will catapult to the stratosphere.

Teaching isn’t just a way to communicate ideas. The act of teaching generates new ideas in the mind of the teacher. Teaching is thinking. Teaching is learning.

Recently, I started the practice of video recording myself where I am pretending as if I am teaching mental models to a class of inquisitive but unforgiving students. This revealed shocking insights! My knowledge was fragile, at best. It rested on few jargons. Believe me, it was maddeningly hard to explain without those jargons. They had become my crutches.

When I dropped those jargons and started looking for commonly used words, my mind went in all directions. That’s where I had to look for analogies. I searched for examples and similarity to other widely known phenomena. This reaching out for making connections deepened my own understanding of those ideas.

I would argue that video recording yourself is Feynman Technique on steroids. Give it a try!

In 2015, Randall Munroe, a cartoonist and creator of wildly popular webcomic XKCD, took up the challenge to write a book which would explain complicated things using a vocabulary of only one thousand simple words. Sticking to his challenge the first thing he did was to get rid of the word “thousand” and replace it with ten hundred. And then he replaces “fifty” with half a hundred. Clever chap!

If you were in his place, what title would you choose for such a book? Well, Munroe called it – The Thing Explainer. What could have been simpler than that?

Let me tempt you by sampling few word combinations that Munroe has used in his book.

• What’s a Laptop? A bending computer.
• What’s an airplane? A sky boat with wings.
• What’s a battery? A power box.
• What’s a pen? It’s a writing stick.
• What’s a rocket? An up goer space boat.

Have you ever wondered why frozen food defrosts unevenly in a microwave oven (or, as Munroe calls it, a “food-heating radio box”)? When you put iced food in a radio box, after a while, parts of it start to turn to water. But since radio boxes are really good at heating water, those parts start to get hot really fast. They can even get so hot they start turning to air—before all the ice is even gone!

If Richard Feynman was alive today, I am sure he would be proud of Munroe’s work.

In the page before the book starts, i.e., the introduction, Munroe writes –

When I was in school, I learned about space boats and learned to use lots of big words for things like the shape of the world. Sometimes I would use those big words because they were different from the small words in an important way. But a lot of the time, I was really just worried that if I used the small words, someone might think I didn’t know the big ones.

I liked writing this book because it made me let go of my fear of sounding stupid. After all—when you’re saying things like “space boats” and “water pushers,” everything sounds stupid. Using simple words let me stop worrying so much. I could just have fun making up new names for things and trying to explain cool ideas in new ways.

Some people say that there’s no reason to learn big words in the first place—all that matters is knowing what things do, not what they’re called. I don’t think that’s always true. To really learn about things, you need help from other people, and if you want to understand those people, you need to know what they mean by the words they use. You also need to know what things are called so you can ask questions about them.

But there are lots of other books that explain what things are called. This book explains what they do.

My kids are too young to read today, but the day they start reading, The Thing Explainer would be waiting for them on the bookshelf, because I want them to think about the Map of the Cat before they get too comfortable with Zoological Charts.

https://www.safalniveshak.com/feynman-map-of-the-cat/