Ancient memory techniques go back to oratorical training in theory, but in practice probably much further back in human history. Philostratus records the reputation of Dionysius of Miletus and his “memory-men”. But one of the most easily abused and likely misunderstood method from the ancient world is the “memory palace” (or “method of loci“), made famous by Cicero, but credited to the lyric poet Simonides.

Cicero De Oratore 2.352–355

“But, so I may return to the matter”, he said, “I am not as smart as Themistocles was as to prefer the art of forgetting to the art of memory. And So I am thankful to that Simonides of Ceos who, as they say, first produced an art of memory. For they say that when Simonides was dining at the home of a wealthy aristocrate named Scopas in Thessaly and had performed that song which he wrote in his honor—in which there were many segments composed for Castor and Pollux elaborated in the way of poets. Then Scopas told him cruelly that he would pay him half as much as he had promised he would give for the song; if it seemed right to him, he could ask Tyndareus’ sons for the other half since he had praised them equally.

A little while later, as they tell the tale, it was announced that Simonides should go outside—there were two young men at the door who had been calling him insistently. He rose, exited, and so no one. Meanwhile, in the same space of time, the ceiling under which Scopas was having his feast collapsed: the man was crushed by the ruins a d died with his relatives. When people wanted to bury them they could not recognize who was where because they were crushed. Simonides is said to have shown the place in which each man died from his memory for their individual burials.

From this experience, Simonides is said to have learned that it is order most of all that brings light to memory. And thus those who wish to practice this aspect of the skill must select specific places and shape in their mind the matters they wish to hold in their memory and locate these facts in those places. It will so turn out that the order of the places will safeguard the order of the matters, the reflections of the facts will remind of the facts themselves, and we may use the places like wax and the ideas like letters written upon it.”

Sed, ut ad rem redeam, non sum tanto ego, inquit, ingenio quanto Themistocles fuit, ut oblivionis artem quam memoriae malim; gratiamque habeo Simonidi illi Cio quem primum ferunt artem memoriae protulisse.  Dicunt enim cum cenaret Crannone in Thessalia Simonides apud Scopam fortunatum hominem et nobilem cecinissetque id carmen quod in eum scripsisset, in quo multa ornandi causa poetarum more in Castorem scripta et Pollucem fuissent, nimis illum sordide Simonidi dixisse se dimidium eius ei quod pactus esset pro illo carmine daturum: reliquum a suis Tyndaridis quos aeque laudasset peteret si ei videretur. Paulo post esse ferunt nuntiatum Simonidi ut prodiret: iuvenes stare ad ianuam duos quosdam qui eum magnopere evocarent; surrexisse illum, prodisse, vidisse neminem; hoc interim spatio conclave illud ubi epularetur Scopas concidisse; ea ruina ipsum cum cognatis oppressum suis interiisse; quos cum humare vellent sui neque possent obtritos internoscere ullo modo, Simonides dicitur ex eo quod meminisset quo eorum loco quisque cubuisset demonstrator uniuscuiusque sepeliendi fuisse; hac tum re admonitus invenisse fertur ordinem esse maxime qui memoriae lumen afferret. Itaque eis qui hanc partem ingeni exercerent locos esse capiendos et ea quae memoria tenere vellent effingenda animo atque in eis locis collocanda: sic fore ut ordinem rerum locorum ordo conservaret, res autem ipsas rerum effigies notaret, atque ut locis pro cera, simulacris pro litteris uteremur.

thanks to S. Raudnitz for reminding me of this passage too!