Today, let's see what happens when our technologies
join forces. 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.
I ask you to try a little
experiment when you have a moment. First find three
metal masses -- nuts, bolts, lead sinkers --
whatever's handy. Hang one on the end of a thread
and swing it. It forms a simple pendulum moving
back and forth, or maybe describing a circle or a
figure eight. Next, take a longer length of thread
and attach all three masses along it -- maybe two
feet apart. Then hang the string of masses from the
ceiling. Start this system swinging and watch what
happens. No matter how they start out, the weights
are soon moving in completely unexpected ways.
The middle one might momentarily stop dead while
the other two gyrate around it. They might all move
in the same plane, or they might swing in circles.
The movements keep changing. When we go from one
mass to a system of three masses, we pass from a
complex, but mathematically tractable motion, to
motion that baffles us.
Our technological systems are like that. Do you
remember October 1987, when a computer-controlled
stock market responded to a ripple in the economy?
We'd told our computers how to respond to certain
market changes, but we were completely unprepared
for their aggregate response. We were stunned when
they flocked together and created the greatest
one-day stock market crash the world had ever seen.
That same complexity lay behind the Three Mile
Island reactor failure. So many elements of the
reactor were interconnected that no operator could
diagnose trouble quickly enough. No one knew how to
correct the situation instead of making it worse.
Yet complex systems are shot through our world
today. A friend, a systems designer, made the point
when he came back from Europe. "John," he said, "I
had a remarkable experience in London. I had to
call home, so I picked up the phone in my hotel,
pushed a few buttons, and found myself talking to
my wife in America."
I looked at him and said, "Yeah, So what?" He
grinned and said, "Stop and think what it took to
do that -- space technology to put up a satellite,
electronic technologies on the ground, radio
technologies in the sky, hotel management systems
..."
"Okay, okay," I cried. Of course he was scolding me
for growing blasé. We depend everywhere on
complexities that outrun our ability to see them
whole. The corollary is that today's engineers have
to spend far more time in the problems of
combining elements effectively than they
spend inventing them in the first place.
Ill-conceived systems threaten us with terrible
mischief. Yet well-combined technologies offer
amazing benefits and conveniences. We've reached
that point in modern engineering, in modern
medicine, even in the social dynamics of our huge
populations. Work on any of these problems in
isolation, when the pieces are all interrelated,
and we'll create mischief rather than solutions.
Forget the interconnection, and we'll be looking at
three metal weights on a string -- spinning and
whirling in mad and incomprehensible ways.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
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