MNEMONICS (ars mnemonica, from the Greek pow.ca,v, memor,) signifies, in the more general sense of the word, the la‘‘ s which regulate the exercise of the faculty of memory ; in its more limited signification, it means a system of rules to assist the memory, by means of association, in recalling past impressions. Such a system was called by the ancients Tizemoria artificialis, to distinguish it from a naturally good memory, unassisted by technical rules.
There is no doubt that the memory is a faculty high ly susceptible of cultivation, and also very capable of being assisted, in many cases, by arrangement and as sociation. We have numerous instances, indeed, both in ancient and modern times, of individuals who pos sessed and exercised this faculty in a very extraordinary degree ; but we are frequently left in doubt whether they depended entirely on the natural strength of an originally good memory, improved, perhaps, by regular and assiduous cultivation ; or whether they had recourse to some mechanical aids. Cyneas, who was sent by King Pyrrhus on an embassy to the Romans, learnt, in the course of one day, the names of all those persons whom he had seen so perfectly, that, on the following day, he could name all the members of the senate, and all the Romans who had assembled round them. King Cyrus could name all the soldiers in his army ; and L. Scipio all the citizens of Rome. i\lithridates, the king of two and twenty nations, held courts in as many lan guages, and could converse with each nation in its own tongue, without using an interpreter. Thentistocles is said to have been oppressed by the strength and tenacity of his memory ; and in the course of a year he-learnt to speak Persic with perfect propriety. Crassus, while governor of Asia, learnt the five Greek dialects so com pletely, that he was able to give judgment in each. Hortensins, the Roman orator, was able to repeat a whole oration in the words he had previously conceiv ed it, without committing it to writing ; and to go through the whole arguments of an opponent in their proper order. It is said, that he once attended a whole
day at a public sale, and, at the end of it, recited, in regular order, the names of all the buyers, the articles sold, and their prices, with perfect exactness. Seneca, in his youth, could pronounce two thousand given words in their proper order ; and having got a verse from each of his school-fellows, he repeated more than two hundred of them from the bottom to the top. Avicen na could with facility repeat the whole books of Aris totle's metaphysics. Picus de Mirandola repeated two thousand names which had been read over to him. Jo seph Scaliger, when a young man, could repeat above one hundred verses, having once read them ; and, in the course of a few weeks, he could repeat the contents of whole books in foreign languages. Magliabechi dictated, from memory, whole books which had been lost. Several individuals are said to have been able to repeat the contents of entire books from the end to the beginning, as is reported of the German poet Klop stock, with respect to Homer, when he was at the school of Porta. William Lyon, a travelling player, repeated the contents of a newspaper from beginning to end. An Englishman once came to Frederick the Great of Prussia, for the purpose of giving him seine specimens of his extraordinary memory. Frederick sent for Vol taire, who read to his majesty a pretty long poem which he had just finished. The Englishman was concealed in such a manner as to be able to hear every word that was said. When Voltaire had concluded, Frederick ob served that a foreign gentleman would immediately re peat the same poem to him, and therefore it could not be original. Voltaire listened with astonishment to the stranger's declamation, and then fell Into a great rage, and tore the manuscript in pieces. When Frederick in formed him of his mistake, the Englishman again dic tated to Voltaire the whole poem with perfect correct ness.