Today, I ask, "Who are you?" The University of Houston's
College of Engineering presents this series about the
machines that make our civilization run, and the people
whose ingenuity created them.
There's been increased interest in
fingerprinting lately. One article, by Melissa Stewart,
goes to the underlying question: "How do you know I am who I say I am?"
That's not the same question as,
"Who dunnit?" Fingerprinting has always found greater use in
certifying identity than it has in nailing crooks.
My 1930 birth certificate includes a print -- not of my
finger, but of my then-tiny foot. Prints are still made
at birth, but they're only for short-term in-hospital
use. Mine was made fewer than twenty years after
fingerprinting had become a mainstream forensic tool, and
it still looked like jazzy hi-tech back then.
Four major identification methods have been used during
the past century and a half: photography, Alphonse
Bertillon's system of body measurement, fingerprints, and
now DNA. Computer people have also been working on quick
recognition methods -- retinal scans, for example. Each
system has had to fight for acceptance, and none has been
cleared of all ambiguity. Photography remains useful,
though we understand its limitations. We can change our
appearance intentionally, or it can change with illness
Body measurement has come and gone. When my great
grandfather came to America in 1843, long before
Bertillon, immigration officials made a lengthy written
list of his features. Bertillon's system of taking
standard body measurements was cumbersome and complex,
and our bodies undergo change with time.
People had already thought about fingerprints when the
Bertillon system went into use. The grandson of
astronomer William Herschel suggested that fingerprinting
might help officials catch scoundrels trying to claim
other people's pension checks.
J. Edgar Hoover made drama of fingerprinting to give the
FBI its hi-tech look during the 1930s. Of course, without
FAXs or copy machines, prints were very hard to use. We
had to rely on a system invented in 1895 by Edward Henry
for describing fingerprints with descriptive symbols. It
was 1967 before we could read and compare prints
All the while, the main use of fingerprinting has
been to create identities -- of runaways, of unidentified
dead, of people already arrested. That's also true for
DNA today. DNA does far more to certify our identity, and
that of our forebears, than it does to catch criminals --
even though the forensic arena is where these methods
have always made the best theater.
But, ever since Martin Guerre --
ever since Oedipus -- identity has posed the more
pressing questions. Am I who I claim to be? My wife likes
to tell me that she wonders if I've been replaced. I take
that as a good sign, since to stay the same can be a kind
of death. Fingerprints or DNA notwithstanding, we had
better change. Still, I'll give her no chance to dust my
footprints. Wouldn't it be terrible to find that the
patterns failed to match, after all?
I'm John Lienhard, at the University of Houston, where
we're interested in the way inventive minds work.