Learning & thinking · a life skill
Deliberate Feynman Explanations
say it out loud, then listen for the gaps
On paper you can pause and tidy. Out loud, with no notes, you can't: every stall and every “basically” lands on the recording. Play it back, mark them, look up only the marks, and record it again.
- Moderate to start
- High impact
- Learn it in 2-4 weeks
- Three minutes a take
Silence is a mark too: the flat stretch at 0:55 is where the explanation ran out. The lookups are the five marks, not the whole topic.
Start with one idea
Try it now.
Your phone's voice recorder and an idea you use but have never explained. Each step below is one part of the chart.
-
Explain it out loud and record it
No notes, no pausing the recording, about three minutes. To a friend if one will listen, to the phone if not.
take 1 · no notes -
Play it back and mark the gaps
Note the time of every stall, every “basically” or “sort of”, and every place you jumped a step.
the stalls and jumps -
Mark the listener's questions
Each question is a gap. Alone? Stop the playback at every word a twelve-year-old would ask about.
“they asked” -
Look up only the marks, then record again
Not the whole topic: the five minutes behind each mark. The next take should be shorter, with fewer marks.
take 1 → take 2 -
Add an analogy, and say where it breaks
An analogy that fits shows you understand it. Saying where it stops fitting shows you understand the analogy.
take 2 → an analogy
For example: you reach the compressor, say “basically it just moves heat”, and stop. That's a mark. The lookup: the compressor squeezes the vapour, which heats it up, so the coils at the back can give that heat to the kitchen.
One idea, said three times
Three takes.
How a fridge keeps food cold, explained out loud with no notes. Each red line is a mark found on the playback.
Take 1no notes
Take 2after the lookups
Take 3the next day
Take 1 ran three minutes with five marks. The lookups took twenty minutes, and take 2 came in at 2:20 with two. The next day, take 3 took under two minutes and nobody had to ask a thing. Shorter is the sign: a gap you fill takes fewer words than a gap you talk around.
The analogy: sweat
Sweat cools your skin by evaporating: turning to vapour takes heat, and it takes it from you. Inside the fridge, a liquid called a refrigerant does the same, taking the heat from the food.
Where it breaks
Sweat is gone once it dries. The refrigerant is caught: the compressor squeezes the vapour, which makes it hot, the coils at the back pass that heat to the kitchen, and it turns back into a liquid to go round again.
The idea
Why it works.
In a 2018 study, Aloysius Koh, Sze Chi Lee and Stephen Lim had students learn a text, then explain it to a video camera. Some explained with no notes, some read from a script. A week later the no-notes group did as well as a group that had practised recalling the text, and both did better than the scripted group and a control group.
Their reading is that teaching helps because it makes you pull the ideas out of memory, and a script takes that away. Researchers still argue over how much more there is to it. But closing the notes is what made the difference in the study, and a recording keeps you honest about it.
Keep it honest
Listen back.
- Don't stop the recording. A restart hides the stall you needed to hear.
- Three minutes, one idea. If it needs ten, it's three ideas. Record them apart.
- Count marks, not minutes. Fewer marks each take is the progress that counts.
- Keep take 1. Played after the last take, it shows what the lookups bought.
Go deeper
Keep going.
- Simple Feynman Explanations
- Deliberate Feynman Explanations
- Advanced Feynman Explanations
Keep this going in the app.
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