The PAO system: how memory champions memorize numbers and cards

How PAO works

Imagine you've prepared a fixed triad for every number from 00 to 99. For example:

To memorize a sequence, you read the elements three at a time: the person of the first, the action of the second, the object of the third. The sequence 07 23 10 becomes:

Change the order and the scene changes: 10 23 07 is Maradona dunking an Aston Martin. Because each position uses a different part of the triad, the order of the three elements is built into the scene itself.

Why it works so well

• Density: three elements per location. A deck of 52 cards fits in 18 locations instead of 52; 30 digits fit in 5 locations.
• Unique scenes: 100 people × 100 actions × 100 objects make a million possible combinations, so every scene is new and distinctive, the distinctiveness effect.
• Speed: once the triads are automatic, you don't invent images while memorizing, you just combine ready-made pieces.

Building a PAO for the numbers 00–99

You need 100 triads, one for each number from 00 to 99 (07 and 7 are different entries: that way any string of digits always splits into pairs). A few ways to choose the people:

• The major system: each digit corresponds to consonant sounds, and the number becomes a word or a name. It's the most systematic method: see the article on the major system.
• Initials: link each digit to a letter (1 = A, 2 = B … 9 = I, 0 = O) and pick a person with those initials: 13 = A.C., 23 = B.C.
• Free associations: numbers that already mean something to you, like shirt numbers, years, ages, or the famous 007.

Mixing methods is fine: what matters is that every number instantly brings its person to mind. Then give each person an action and an object that are typical of them: it's much easier to remember that Jordan dunks a basketball than an arbitrary action.

Building a PAO for cards

For cards you need 52 triads. The simplest trick is to start from the people you may already use for cards (see how to memorize a deck of cards) and give each of them a characteristic action and object. With three cards per location, a deck takes 17 full scenes plus one location for the last card: 18 locations in total.

How to build it without giving up

1. Don't do it all in one evening. Ten triads a day is a sustainable pace: the numbers are done in ten days.
2. Start with the people, test them in a few sessions, then add actions and objects.
3. Make actions and objects clearly different from each other. “Runs” and “jogs” will get mixed up; “runs” and “juggles” won't.
4. Write everything in one place and fix it as you go: no system is perfect the first time.

On Loci you can write your system in the PAO editor on the Practice page, for numbers and for cards. You can start training as soon as you have a few complete entries: sessions only use the entries you've filled in.

Using PAO in a memory palace

Memorizing works as with any other image: one scene per location, walking the route in order. To recall, walk it again and decode each scene: the person gives you the first element, the action the second, the object the third.

A common mistake is to glance at the scene too quickly without really imagining it. Give every scene at least one concrete detail (a sound, a colour, the person's reaction) and tie it to the location: Bond dunking a football smashes your kitchen lamp.

Frequently asked questions