Marcus Tullius Cicero, who lived from 106 B.C. to 43 B.C., described in his
De ora tore how Simonides of Ceos invented the art of memory: the
mnemonic of places and images, or loci and imagines (Herrmann & Chaffin, 1988; Yates, 1966). Apparently, while Simonides was dining at the house of a nobleman named Scopas, he composed and recited a poem in honour of his host. However, in the poem he also included a passage
honouring Castor and Pollux, and so Scopas nastily informed him that h e was paying for only half the agreed fee - that Simonides could obtain the balance from the two gods to whom he decided to devote half of the poem. Later in the evening, Simonides received a message that two young men were waiting outside wanting to talk to him, but when h e went outside there was no one there. While he was outside, the roof o f the dining room collapsed, crushing Scopas and all his other guests to death. Thus, as Cicero interpreted it, the invisible callers Castor and Pollux paid for their share of the poem by saving Simonides' life! Apparently, the bodies in the dining room were so mangled that their relatives could not identify them. However, Simonides remembered the places where they were sitting and therefore was able to show the relatives which of the dead belonged to them. The whole experience suggested to Simonides the importance of an orderly arrangement for a clear memory. He inferred that if a person wants to train their memory they must select localities, form mental images of the facts they wish to
remember, and store those images in the localities. Later they can
retrieve those facts by mentally going through the arranged localities with the associated images representing the facts.
Apart from the description given by Cicero, the method of loci was also discussed by two other 'ancient' authors: one was an unknown teacher who wrote Ad Heren n i u m around 86 to 82 B.C., and the other was Quintillian (c. 40 A.D. - c. 96 A.D.) who wrote Institutio oratoria. Essentially, the method requires committing to memory a series of loci or places. The most common type used was architectural structure. In fact, Quintillian advised on a spacious and many-featured building that includes the forecourt, the living room, the bedroom, the parlours, the statues and other ornaments decorating the rooms, and so on. Images are then created of the speech to be remembered, and these images are placed in imagination on the places that have been sequentially committed to memory. After doing this, and when the facts/speech details have to be
recalled, one has to mentally visit the places in the right sequence and retrieve the images that have been placed in each of them.
Yates (1966) noted that nowadays it may be rather difficult to appreciate the value and utility of this mnemonic technique, but she put in a reminder that in the ancient world there was no printing, no paper for notetaking or typing of lectures, and thus a trained memory was extremely important for some. She described an ancient orator - for whom essentially the method of loci was devised - as moving i n imagination through the building he has memorised whilst reciting his speech. From the memorised places he extracts the images he had placed on them, thus making sure that the parts of the speech are remembered in the right order, since the places in the building are revisited in a fixed sequence.
The anonymous author of Ad Herennium described an example of how a concept or idea can be represented by a multi-faceted image which can then be associated with a location, which he referred to as the "background" :
Often we encompass the record of an entire matter by one notation, a single image. For example, the prosecutor has said that the defendant killed a man by poison, has charged
that the motive for the crime was an inheritance, and declared that there are many witnesses and accessories to this act. If in order to facilitate our defence we wish to
remember this first point, we shall in our first background form an image of the whole
matter. We shall picture the man in question as lying ill in bed, if we know his person. I f we do not know him, we shall yet take someone to be our invalid, but not a man of the
lowest class, so that he may come to mind at once. And we shall place the defendant a t the bedside, holding in his right hand a cup, and in his left tablets, and en the fourth finger a ram's testicles. In this way we can record the man who was poisoned, the
inheritance, and the witnesses. In like fashion we shall set the other counts of the charge in background successively, following their order, and whenever we wish to remember a
point, by properly arranging the patterns of the backgrounds and carefully imprinting the images, we shall easily succeed in calling back to mind what we wish. (Anonymous, c. 86 B.c.: in Herrmann & Chaffin, 1988, p. 89)
Although noting that this mnemonic device certainly has its uses, Quintillian had reservations about its usefulness in remembering connected speech (cited in Herrmann & Chaffin, 1988). He pointed out that certain things, such as conjectures, are impossible to represent by symbols. He also believed that the flow of speech will inevitably be hampered by the double task imposed on memory - of having to utter words in a flowing manner and at the same time look back at separate symbols for each individual word. He advised instead that if a long speech needs to be remembered, one should learn it piecemeal since memory does not respond very well to being overburdened.
D' Assigny (1985, originally published in 1697) also did not have absolute faith in the method of loci (which he described in the final chapter of his book), primarily because he believed that it depends too much on the strength of an individual's imagination. He did think that it could sometimes be useful, but the main focus of his book was on teaching ways to improve the natura l powers of memory. Like many during his time, he believed that animal spirits formed the basis of memory, and that it was necessary to ensure the maintenance of bodily equilibrium through proper regimen and medical treatment if one were to have good memory. For example, he recommended moderation in intake of food and drink, getting sufficient exercise, ensuring that the head and feet are not exposed to too much cold, and avoiding sexual excess - especially on a full stomach or out of wedlock!
Yates (1966) was more positive towards the method of loci, and paid particular attention to the one described in Ad Herennium, where the anonymous author gave a detailed description of the method (in contrast to Cicero's and Quintillian's writings which both assumed that the reader already knew of the technique and the associated terminology). Whil e acknowledging that a tremendous amount of effort is required to carry out these "mnemonic gymnastics," she had no doubt that they work. I n her book, The art of mem ory, she pointed out the great importance
through the ages of Ad Herennium: how the practice of memory as an art in the Western tradition was so much dependent on the memory section of this document. Ad Heren n i u m was well known and much used during the Middle Ages and during the Renaissance. Every mnemonic technique devised in the Western world, even the mysterious and occult systems of the Renaissance, subscribed in one way or another to the basic plan of Ad Herenniu m : its rules for places, rules for images, memory for things, and memory for words.
The long history of fact mnemonic use can be considered a testimony to its capacity to address an important need in humans: the need to remember various facts. Whether the facts that need to be remembered concern the sequence of an oratory or the details of a court proceeding, the use of mnemonics is very understandable prior to the availability of paper. It would have been impractical to construct stone tablets to record the details of every speech, let alone to lug the heavy tablets around for the simple purpose of consulting them. However, that their use survived the advent of paper suggests that there is a little more to them than just an alternative to reminder notes.