1 UNFORGETTABLE It was only midmorning on April 13, 1929, but Solomon Shereshevsky was already having a bad day. The journalist had just attended the daily editorial meeting of his Moscow newspaper when his section editor called him into his office. What was Shereshevsky playing at? his agitated superior asked him. Why did he just stare at the editor while he ran over the day''s stories? Was he too full of himself to take notes like all the other reporters? Nonplussed, Shereshevsky explained that he didn''t need to take notes, because he remembered everything the editor said. Then he proceeded to recite the entire meeting back to him. Verbatim. By that afternoon Shereshevsky found himself amid a gaggle of psychiatrists at the Academy of Communist Education, among whom was a young doctor, Alexander Luria. Luria took on the task of testing Shereshevsky''s memory, which he did by reading him increasingly long lists of random words and numbers and asking him to recall them.

By the end of the day Luria had to admit that the capacity of Shereshevsky''s memory "had no distinct limits." As Shereshevsky would later recount, until that day he had no idea his abilities were anything other than normal. When he returned to work, he delivered to his editor the verdict of the state''s psychiatric experts: his memory exceeded "the bounds of what was believed to be physically possible." His editor promptly advised him to change careers. So Shereshevsky found a circus trainer to manage him and began booking shows around the country as a mnemonist. Despite his natural talent, Shereshevsky had to work hard at his new career, and he developed techniques to push his capacity ever further. To be able to recite back the lists of numbers, random words, poems in foreign languages, and even nonsensical syllables that audience members would call out to him, he landed on the strategy of picturing them drawn on a chalkboard. When it came time to recall the lists, he would return to this mental chalkboard and simply read from it out loud.

To his horror he soon discovered that the very indelibility of his memory could interfere with his performance. Closing his eyes and finding his way back to the board on which he had arranged the sounds and images, he might instead come upon the board from an earlier performance and read back that list. To counteract this danger, he found he had to mentally erase or otherwise destroy the writing on his mental board. In short, to remember better, he had to learn to forget. This interference didn''t wane with time. Luria, who continued to study Shereshevsky for decades, discovered he could flawlessly recall lists Luria had used to test him fifteen years prior. In fact, Shereshevsky waged an almost constant war against the images and associations from the past that threatened to flood his every waking moment. It wasn''t just memories that menaced his perception of the present.

Shereshevsky suffered from synesthesia, sensory crossover. A sound of a certain pitch might produce a coppery taste on his tongue; numbers appeared as specific figures with rich, unchanging characteristics. For most of us, 87 is a number, say, of pages read or years lived; Shereshevsky saw it as "a fat woman and a man as individuals, not instances of a general system. He once exerted intense effort to memorize a vast table of numeric sequences, failing to notice that it followed a rule of such simplicity that a child could reproduce it ad infinitum, because each line simply started with a higher integer than the previous one. For Luria it soon became clear that Shereshevsky''s remarkable ability came with an equal disability. He lived in a world of particulars, "rich in imagery, thematic elaboration, and effect," but also "peculiarly lacking in one important feature: the capacity to convert encounters with the particular into instances of the general." To understand the intended meaning of a normal sentence, Shereshevsky had to overcome his sensual experience of how a word sounded here and now; he had to forget his immersion in the present and connect to a different moment in space and time, an endeavor that would at times prove impossible. In truth, he struggled mightily with the very aspect of language that makes it function in human communication and knowledge.

Even our most common expressions contain words that we use figuratively, or that have different meanings in different situations. A nightmare for Shereshevsky. The simple act of "catching a cab" would present him with a barrage of possible interpretations to contend with. As he would later explain to Luria, the word ekipazh means "cab," but it also means "the crew of a ship." To understand the one meaning, he had to "picture for myself not just a driver in the cab but an entire staff manning it. That''s the only way I can make sense of it." Living in a world of particulars, being constantly bathed in the immediate, makes communication a difficult affair. Language loses its ability to connect two disparate agents, to translate the experience of the one into the context of the other.

But more than just a stumbling block for understanding what others were saying to him, in Shereshevsky''s world, as the neuroscientist Jerome Bruner would later put it, "elements and features can be isolated, but a ''whole'' or meaningful picture cannot be put together." Indeed, it seems that the more perfect Shereshevsky''s extraordinary memory, the less he had a coherent self who could remember. For a brief time, Shereshevsky''s feats brought him fame and a sustainable existence. But even as stories of the man who couldn''t forget seeped into the outside world, life behind Stalin''s iron curtain was getting harder, especially for Jews like Luria and Shereshevsky. After the war, as Stalin consolidated his power through "anti-cosmopolitan" purges, Luria lost his position for a time and took to keeping a bag packed in case the authorities came for him in the night. Shereshevsky, who had refused to lend his talents to the secret police, found himself followed and harassed, his performances interrupted, and his career eventually ruined. Luria would regain his footing and become one of the preeminent neuropsychologists of the twentieth century, his analysis of Shereshevsky a profound influence for later scientists like Jerome Bruner and Oliver Sacks. Shereshevsky, for his part, learned another way of erasing or at least dampening the remembered and perceived sensorium that had become his prison house.

He started drinking heavily and died in obscurity a few years later.