Would you keep every memory?

You have already forgotten most of your life: nearly all of last Tuesday, most of your seventh year, the faces of almost everyone you have ever passed. Usually you notice only when it hurts, as a name that won't come or a grandparent's voice going faint. Some people would take the opposite deal gladly. Starting in 1998, the computer scientist Gordon Bell set out to record his whole life, scanning his papers, saving his email and calls, and wearing a camera around his neck that took pictures through the day. He and Jim Gemmell went on to write a book predicting that total recall would change everything. Jorge Luis Borges imagined the cost in 1942. In Funes the Memorious, a young man thrown from a horse wakes able to remember everything, down to the shapes of the clouds on one particular dawn years before. He is also, the narrator suspects, barely able to think: it troubles him that one word, dog, should cover so many different animals. Nietzsche had made a similar case for living: we can act only because we forget, much as we stay well only because we sleep. Some of the rare people who really do remember their own lives in detail call it a burden, though most of those studied say it isn't. Jill Price, the first person documented with what researchers now call highly superior autobiographical memory, has described old hurts coming back to her with their original force. Meanwhile psychologists have shown that ordinary memory rebuilds the past more than it records it. In 1932 Frederic Bartlett reported how a strange folk tale, retold from memory again and again, reshaped itself into something more familiar. In 1974 Elizabeth Loftus and John Palmer found that asking how fast filmed cars were going when they smashed, rather than hit, each other made viewers likelier to recall broken glass that was never there. If memory were yours to set, how would you set it?