The gift of being able to describe a face accurately is a rare one, as every experienced police
officer knows to his cost. As the Lancet put it recently, "When we try to describe faces precisely,
words fail us, and we resort to identikit (拼脸型图) procedures."
     Yet, according to one authority on the subject, we can each probably recognize more than
1,000 faces, the majority of which differ in fine details. This, when one comes to think of it, is a
tremendous feat, though, curiously enough, relatively little attention has been devoted to the
fundamental problems of how and why we acquire this gift for recognizing and remembering faces.
Is it an inborn property of our brains, or an acquired one? As so often happens, the experts tend
to differ.
     Thus, some argue that it is inborn, and that there are "special characteristics about the brain's
ability to distinguish faces". In support of this, they note how much better we are at recognizing a
face after a single encounter than we are, for example, in recognizing an individual horse. On the
other hand, there are those, and they are probably in the majority, who claim that the gift is an
acquired one.
     The arguments in favor of this latter view, it must be confessed, are impressive. It is a habit that
is acquired soon after birth. Watch, for instance, how a quite young baby recognizes his mother by
sight. Granted that his other senses help - the sound, his sense of smell, the distinctive way she
handles him. But of all these, sight is predominant. Formed at the very beginning of life, the ability
to recognize faces quickly becomes an established habit, and one that is, essential for daily living,
if not necessarily for survival. How essential and valuable it is we probably do not appreciate until
we encounter people who have been deprived of the faculty.
     This unfortunate inability to recognize familiar faces is known to all, but such people can often
recognize individuals by their voices, their walking manners or their spectacles. With typical human
ingenuity, many of these unfortunate people overcome their handicap by recognizing other
characteristic features.