Kluge: The Haphazard Construction of the Human Mind (Houghton Mifflin; 2008)

Or consider another common quirk of human memory: the fact that our memory for what happened is rarely matched by memory for when

it occurred. Whereas computers and videotapes can pinpoint events to the second (when a particular movie was recorded or particular file was modified), we're often lucky if we can guess the year in which something happened, even if, say, it was in the headlines for months. Most people my age, for example, were inundated a few years ago with a rather sordid story involving two Olympic figure skaters; the ex-husband of one skater hired a goon to whack the other skater on the knee, in order to ruin the latter skater's chance at a medal. It's just the sort of thing the media love, and for nearly six months the story was unavoidable. But if today I asked the average person when it happened, I suspect he or she would have difficulty recalling the year, let alone the specific month.*

For something that happened fairly recently, we can get around the problem by using a simple rule of thumb: the more recent the event, the more vivid the memory. But this vividness has its limits: events that have receded more than a couple of months into the past tend to blur together, frequently leaving us chronologically challenged. For example, when regular viewers of the weekly TV news

Th e principals involved were Tonya Harding, Jeff Gillooly (her ex-husband), and Nancy Kerrigan; Gillooly's hired goon went after Kerrigan's knee on January 6,1994. Bonus question: When did the Rwandan genocide begin? Answer: April of that same year, three months after the onset of Tonyagate, which was still a big enough story to obscure the news from Rwanda. In the words of the UN commander on the scene, Romיo Dallaire, "During

the 100 days of the Rwanda genocide, there was more coverage of Tonya Harding by ABC, CBS, and NBC than of the genocide itself."

program 60 Minutes

were asked to recall when a series of stories aired, viewers could readily distinguish a story presented two months earlier from a story shown only a week before. But stories presented further in the past — say, two years versus four — all faded into an indistinct muddle.

Of course, there is always another workaround. Instead of simply trying to recall when something happened, we can try to infer this information. By a process known as "reconstruction," we work backward, correlating an event of uncertain date with chronological landmarks that we're sure of. To take another example ripped from the headlines, if I asked you to name the year in which O. J. Simpson was tried for murder, you'd probably have to guesstimate. As vivid as the proceedings were then, they are now (for me, anyway) beginning to get a bit hazy. Unless you are a trivia buff, you probably can't remember exactly when the trial happened. Instead, you might reason that it took place before the Monica Lewinsky scandal but after Bill Clinton took office, or that it occurred before you met your significant other but after you went to college. Reconstruction is, to be sure, better than nothing, but compared to a simple time/date stamp, it's incredibly clumsy.