THE ART OF MEMORY · LESSON 19 OF 30 · PART IV: LANGUAGE AND STUDY

Formulas as Characters

A clerk in a patent office changed physics in one year. You will turn five famous formulas into short scenes you can read like a sentence.

Memory hook: a young patent clerk watches a tiny stage where a giant lifts a boulder while a comet circles twice: a formula acted out by characters.

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In this lesson: you will turn five formulas into stories where each symbol is a character, read the formulas back from the stories, and learn why meaning comes first.
Where we left off
What is the first letter of the code word for T? And for Q?
Tango and Quebec.
How many pegs does the alphabet system have?
Twenty-six.
How would you use the pegs for a procedure with six steps?
Put each step on a peg A to F, as an action on the peg.

The clerk who changed the world in a year

Bern, Switzerland, 1905. A young man in his twenties sits at a high desk in the patent office, reading other people's ideas for new machines. He is a clerk, and nobody thinks of him as a scientist. At home, in his spare time, he is thinking about the nature of light, time and space.

In that one year he sent four papers to a leading German journal. Any one of them would have made his name. They explained how light carries energy in small packets, how tiny particles in water jiggle, how time and space change at high speed, and, in a short paper at the end of the year, how mass and energy are connected. His name was Albert Einstein.

What was Einstein's job in 1905?
He was a clerk in a patent office in Bern, working on physics in his spare time.
Talk about it. What would you do with spare time and a hard question? Would you work on it alone, or with other people?

The last paper gave the world the most famous formula ever written: E = mc². Energy equals mass times the speed of light, squared. Five characters, and yet they say that a tiny amount of matter holds an enormous amount of energy.

Millions of people know this formula without knowing what it means. And that is a clue to something about memory. You can remember a formula as a picture of symbols, but if you do not understand it, it will not last, and you will not know when to use it. A formula is a sentence. First understand what it says.

What does E = mc² say?
Energy equals mass times the speed of light squared: a little mass holds a huge amount of energy.
Talk about it. Explain E = mc² in your own words, as if to a ten-year-old.

Once you understand a formula, the problem is the symbols. E, m, c, a little 2: they look like nothing. They are abstract, and we found in the last lessons what the mind does with abstract things: it lets go.

So we give them life. Each symbol becomes a character, each operation an action, and the whole formula becomes a short scene. It sounds silly, and it is: that is what makes it work.

Why do symbols need characters?
Symbols are abstract, and abstract things are forgotten. A character you can picture holds them.
Talk about it. Which formulas or rules do you still remember from school? How do you remember them?

Words worth knowing

Say what you think each one means, then open it.

a rule written in symbols. A formula for the area of a circle.
a sign that stands for something else. E is the symbol for energy.
to multiply a number by itself. Four squared is sixteen.
the amount of matter in an object.
the distance from the centre of a circle to its edge.
the distance round the outside of a circle.

Einstein's 1905 papers: the mass-energy paper appeared in the same year as the other three. Told here in our own words.

A character for every symbol

Understand the formula first. Then make it a scene.

  1. Say what it means. In words, in one sentence. 'Force equals mass times acceleration.'
  2. Give each symbol a character. Use the first letter or the meaning: E = eagle (energy), m = mouse (mass).
  3. Give each operation an action. '=' is a balance or a table; '×' is a crossing; '²' is a twin or a square box; '+' is a joining.
  4. Join them in one scene. The characters, in the same order as the formula, doing the actions.
  5. Test it with a number. Put in simple numbers and check the result. If it works, the formula is yours.
FormulaMeaningThe scene
E = mc²Energy equals mass times the speed of light squaredAn Eagle is carried by a Mouse riding a Cheetah, twice round the track.
F = maForce equals mass times accelerationA Fist hits a Mouse and he flies away like an Arrow.
a² + b² = c²In a right-angled triangle, the squares on the two shorter sides add up to the square on the longest sideA ladder (c) leans against a wall (a) and a floor (b): two small gardens plus a medium one fill one big garden.
C = 2πrCircumference equals two times pi times the radiusA Cheetah runs twice round a giant Pie (π) with a Rabbit in the middle.
A = πr²Area equals pi times the radius squaredA pie cut into a perfect circle: a Rabbit, twice, sits on top of the pie (π): that is the Area.
E = mc² as a scene
E = mc²
EAn Eagle (energy).
=A balance, or a table where it sits.
mA mouse (mass).
cA cheetah (the speed of light, the fastest thing there is).
²Twice round: two laps, or two cheetahs.
The picture: An eagle is perched on a balance, and a tiny mouse riding a cheetah races round twice, lifting the eagle sky-high.

Meaning before pictures

  • Understand first. A picture of a formula you do not understand will fade; a picture of one you do will stay.
  • Check with numbers. If the sides of a triangle are 3 and 4, the longest side is 5: 9 + 16 = 25.
  • Say it in words. If you can say it, you can build the scene.
  • Review formulas the way you review any list: soon, then at longer gaps.
understand,
then picture,
then test with numbers.
Say it aloud. Say each of the five formulas aloud in words, then tell the scene for one of them.

Now you build

Have a go before you open any answer. A rough attempt teaches you more than a perfect model you only read.

Symbols and characters

Match each symbol to the character used in the scenes above.
E
m
c (speed of light)
π
r

Read the formulas

F = ma means force equals times acceleration.
In a right-angled triangle with shorter sides 3 and 4, the longest side is .
The circumference of a circle is 2 × pi × the .

Build F = ma

Write your own scene for F = ma. Use a character for each symbol, and an action for each operation.
A giant Fist is punching a Mouse across the room. The mouse flies away faster and faster like an Arrow. The harder the fist (force), the faster the mouse goes.

Build the Pythagorean theorem

Make one scene for a² + b² = c². Then test it with 3, 4 and 5.
A ladder (c) leans on a wall (a) with its foot on the floor (b). The wall's garden (a-squared) and the floor's garden (b-squared) are poured into the ladder's giant square (c-squared), and exactly fill it. Test: 9 + 16 = 25.

Two circle formulas

Make scenes for C = 2πr and A = πr². Make sure the two scenes are different enough not to mix.
C: a Cheetah runs twice round a giant Pie with a Rabbit in the middle. A: a Rabbit sits on a pie, twice, and that is the Area of the pie. Give C a race and A a picnic.
A formula you do not understand but have memorised as a picture will...

Teach it

Explain one of the five formulas to an imaginary student in one minute: what it says, the scene, and a number example.
1:00

Drill

Flash cards

Say the answer first, then tap the card.

tap to turn over

Quick quiz

In a right-angled triangle with shorter sides 6 and 8, what is the longest side?
What does the 'squared' sign in E = mc² apply to?
What is the first step in memorising a formula?
Which formula uses pi and a radius that is squared?

The memory challenge

Memory challenge: five formulas

Learn the five scenes in order. Type the five formulas, one per line, like 'E = mc2'.

An eagle on a mouse on a cheetah; a fist, a mouse and an arrow; a ladder; a cheetah round a pie; a rabbit on a pie.

0:00

The list has gone. Type what you remember, one item per line.

Look back

These reach back to earlier rooms. Answer in your head or out loud, then check.

Lesson 18 · Twenty-Six Pegs. What is the code word for K, M and Q?
Kilo, Mike, Quebec.
Lesson 17 · Verbs That Misbehave. What is the past participle of 'swim'?
Swum.
Lesson 16 · Words in a New Language. What does the root 'ject' mean?
Throw.
Lesson 5 · Links and Stories. When is a story chain a good tool?
For a short list you need quickly, with no place to use.

What I can do now

A thought to keep

Which formula or rule do you most often forget? What would its characters be?

Saved on this device as you type.