It would be far from easy to pronounce what person has been the most remarkable for the excellence of his memory, that blessing so essential for the enjoyment of life, there having been so many who have been celebrated for it. King Cyrus knew all the soldiers of his army by name:[1085] L. Scipio the names of all the Roman people. Cineas, the ambassador of king Pyrrhus, knew by name all the members of the senate and the equestrian order, the day after his arrival at Rome. Mithridates,[1086] who was king of twenty-two nations, administered their laws in as many languages, and could harangue each of them, without employing an interpreter. There was in Greece a man named Charmidas, who, when a person asked him for any book in a library, could repeat it by heart, just as though he were reading. Memory, in fine, has been made an art; which was first invented by the lyric poet, Simonides,[1087] and perfected by Metrodorus of Scepsis, so as to enable persons to repeat word for word exactly what they have heard.[1088] Nothing whatever, in man, is of so frail a nature as the memory; for it is affected by disease, by injuries, and even by fright; being sometimes partially lost, and at other times entirely so. A man, who received a blow from a stone, forgot the names of the letters only;[1089] while, on the other hand, another person, who fell from a very high roof, could not so much as recollect his mother, or his relations and neighbours. Another person, in consequence of some disease, forgot his own servants even; and Messala Corvinus, the orator, lost all recollection of his own name. And so it is, that very often the memory appears to attempt, as it were, to make its escape from us, even while the body is at rest and in perfect health. When sleep, too, comes over us, it is cut off altogether; so much so, that the mind, in its vacancy, is at a loss to know where we are.[1090] CHAP. 25. (25.)—VIGOR OF MIND.