Method of Loci

memory palace

A memory palace is an ancient mnemonic device that leverages the way we find it easiest to recall information: spatially and visually.

You might have experienced the power of spatial memory if you’ve ever revisited a place where you experienced something unpleasant or sad. Minor details might have been enough to make you vividly remember the experience.

According to legend, the renowned Greek lyric poet Simonides of Ceos was dining at the home of a wealthy nobleman one night when he received word that two young men were waiting outside with a message for him. Simonides stepped outside—mere moments before the roof of the banquet hall caved in, killing everyone inside. The extent of the destruction was so great that the family and friends of the deceased guests despaired of being able to identify their bodies.

But Simonides found that if he pictured the spatial layout of the hall, he could mentally walk around it and recall the names of the guests seated in each place. In this way, he helped identify the unfortunate diners. From this experience, Simonides deduced that remembering factual information is easiest if we tie it to a physical location we are familiar with. As the great orator Cicero explained:

“He inferred that persons desiring to train this faculty must select localities and form mental images of the facts they wish to remember and store those images in the localities, with the result that the arrangement of the localities will preserve the order of the facts, and the images of the facts will designate the facts themselves, and we shall employ the localities and images respectively as a wax writing tablet and the letters written on it.

… It has been sagaciously discerned by Simonides or else discovered by some other person that the most complete pictures are formed in our minds of the things that have been conveyed to them and imprinted on them by the senses, but that the keenest of all our senses is the sense of sight, and that consequently perceptions received by the ears or by reflection can be most easily retained in the mind if they are also conveyed to our minds by the mediation of the eyes, with the result that things not seen and not lying in the field of visual discernment are earmarked by a sort of image and shape so that we keep hold of as it were by an act of sight things that we can scarcely embrace by an act of thought.”

Remembering numbers
The memory palace is a great way to recall a variety of things, but you will still hit a hard ceiling, and that ceiling conflicts with the Herculean amount of numbers some memory competitors can remember. What’s the trick? It turns out that there is a whole different tool just for recalling numbers.

PAO: Person – Action – Object
In this system, every two-digit number from 00 to 99 is processed into a single image of a person performing an action on an object. Joshua Foer writes:

“The number 34 might be Frank Sinatra (a person) crooning (an action) into a microphone (an object). Likewise, 13 might be David Beckham kicking a soccer ball. The number 79 could be Superman flying with a cape. Any six-digit number, like say 34-13-79, can then be turned into a single image by combining the person from the first number with the action from the second and the object for the third – in this case, it would be Frank Sinatra kicking a cape.”