# You think you understand it? Close your notes and explain it to a 12-year-old: the Feynman technique step everyone skips

> The Feynman technique means explaining a topic in plain words until the gaps show. Why it works, the 4 steps, and the one most guides skip: no notes.

Category: Practical. Published 2026-10-30, updated 2026-10-30.
About 5 minutes to read. URL: https://www.memorypilot.fr/en/blog/feynman-technique

The **Feynman technique** is learning something by explaining it in plain words, as if to a 12-year-old, until the gaps in your understanding show up. It works, but mostly for a reason most guides skip: you have to explain it **with your notes closed**. Read your explanation off the page, and most of the benefit disappears.

You watched the lecture, read the chapter, nodded at every slide. Then a friend asks “so how does it actually work?” and you hear yourself say “it’s… basically… kind of complicated”.

## What is the Feynman technique?

The Feynman technique is a four-step study method built on one idea: if you can’t explain something simply, you don’t understand it yet. The steps, as they are usually taught:

- **Pick a concept** and write it at the top of a blank page.
- **Explain it in plain words**, as if to a 12-year-old: no jargon you can’t unpack.
- **Go back to the source** where you got stuck, and only there.
- **Simplify again**, with an example or an analogy.

It carries the name of Richard Feynman, the Nobel-winning physicist famous for explaining hard physics in everyday language. But he never wrote these four steps down. The method, and its name, spread through study blogs around 2011, notably [Scott Young’s “Learn Faster with the Feynman Technique”](https://www.scotthyoung.com/learnonsteroids/learnfast.html), more than twenty years after Feynman’s death in 1988.

## Why it works: you understand less than you think

Explaining works because it exposes an illusion: we feel we understand familiar things far better than we do. In 2002, Leonid Rozenblit and Frank Keil asked Yale graduate students to rate, from 1 to 7, how well they understood everyday objects such as a **zipper**, a flush toilet or a piano key. Then they had to write out, step by step, how each one works, and rate themselves again. Nearly all the ratings dropped ([Rozenblit and Keil, 2002](https://doi.org/10.1207/s15516709cog2605_1)). The researchers called it the **illusion of explanatory depth**.

You use a zipper every day. Try explaining how it closes, right now. Studying works the same way: rereading makes a page familiar, and familiar feels understood. It’s the same trap that makes [rereading so misleading](https://www.memorypilot.fr/en/blog/active-recall). Trying to explain is what breaks the spell.

![Close-up of a worn chalkboard filled with handwritten differential equations, a curly bracket on the left and a short inequality boxed on the right.](https://www.memorypilot.fr/img/article/tableau-noir-formules.webp)

*Copying the board feels like understanding. Explaining it with the board wiped is the real test. (Roman Mager roman_lazygeek, CC0, via Wikimedia Commons)*

## The step everyone skips: close your notes

Explaining helps you learn mainly because it forces you to **pull the material out of memory**. In 2018, Aloysius Koh, Sze Chi Lee and Stephen Lim had students study a text, then do one of four things: teach it on video without notes, write down everything they remembered, read a prepared teaching script aloud on camera, or do an unrelated task. On the final test, teaching without notes and the memory test did about equally well, and both clearly beat reading the script ([Koh, Lee and Lim, 2018](https://doi.org/10.1002/acp.3410)).

The authors conclude that the gain comes from retrieval, not from explaining as such. Other researchers think explaining adds something of its own, and the debate is open ([Kobayashi, 2022](https://doi.org/10.3389/fpsyg.2022.842668)). But both sides agree on the practical rule: **explain from memory first, check afterwards**. With your notes open, you’re just reading aloud.

## How to use the Feynman technique tonight, in 4 steps

### 1. Turn the topic into a question

Not “Chapter 4: photosynthesis”, but “how does a plant turn light into sugar?”. A question tells you when your explanation is finished. Keep it small: one mechanism, one idea, ten minutes.

### 2. Explain it out loud, notes closed

To an imaginary 12-year-old, a patient friend or your phone. Out loud is faster than writing, and recording a [voice memo](https://www.memorypilot.fr/en/blog/voice-memos-to-notes-iphone) lets you hear yourself afterwards. Any technical word you use, you have to define in plain words.

### 3. Circle where you stalled

The gaps announce themselves: “basically”, “sort of”, a long pause, a term you couldn’t unpack. Write each one down. Only now open your notes, and fix **only those spots**. The rest you already know.

### 4. Explain it again tomorrow, shorter

Find an example or an analogy, then explain the whole thing again the next day, still without notes. One day later is when [the forgetting curve](https://www.memorypilot.fr/en/blog/forgetting-curve) bites hardest, and a second explanation is what makes the knowledge stay.

**The test to keep**

**If you can only explain it with your notes open, you don’t know it yet: you recognize it.** Close them, explain, then check.

Step 4 is the one that slips. With [MemoryPilot](https://www.memorypilot.fr/en), you say “remind me tomorrow at 6 to explain photosynthesis again, without notes”, along with the two gaps you circled, and it brings both back at 6.

## The surprise: you don’t even need someone to explain to

In 2014, John Nestojko and his colleagues had students read a passage. Some were told they would be tested on it; others that they would have to teach it to another student. In the end, everyone took the test and nobody taught. The students who expected to teach still recalled more, organized it better, and remembered the main points better ([Nestojko and colleagues, 2014](https://doi.org/10.3758/s13421-014-0416-z)).

Just planning to explain changes how you read: you look for the main idea, the order, the example. So tonight, before you open the chapter, tell yourself you’ll explain it to someone tomorrow. Feynman put the rule more bluntly in a 1974 speech at Caltech: the first principle is not to fool yourself, and you are the easiest person to fool ([the full speech](https://calteches.library.caltech.edu/51/2/CargoCult.htm)). Explaining with your notes closed is how you stop. For the rest of the toolkit, see [how to remember things](https://www.memorypilot.fr/en/blog/how-to-remember-things).

## Frequently asked questions

### What is the Feynman technique?

The Feynman technique is a study method where you explain a concept in simple words, as if to a 12-year-old, to find out what you don’t understand. Wherever your explanation stalls or falls back on jargon, you return to the source, fix that gap, and explain again more simply. It is named after physicist Richard Feynman.

### What are the 4 steps of the Feynman technique?

Pick a concept and write it down. Explain it in plain words as if teaching a 12-year-old, without looking at your notes. Go back to the source only where you got stuck. Then simplify your explanation with an example or analogy, and explain it again later. The closed notes in step two are what make it work.

### Does the Feynman technique actually work?

Yes, with a condition. Research on learning by teaching finds that explaining without notes improves retention about as much as self-testing, while reading a prepared explanation aloud helps much less (Koh, Lee and Lim, 2018). The benefit comes largely from pulling the material out of memory, so the explanation must come from your head.

### Is the Feynman technique the same as active recall?

It is one form of active recall. Active recall means retrieving information from memory instead of rereading it; the Feynman technique does that by asking you to explain the topic simply, with your notes closed. Its extra benefit is that explaining exposes gaps in understanding, not just facts you forgot.