Today, we cut with Occam's razor. 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.
You all know that wonderful
old Shaker tune,
'Tis a gift to be simple, 'tis a gift to be
free;
'Tis a gift to come down where you ought to
be
Those lines should make up the first chapter in any
book on engineering design. But how do we find the
natural threads of simplicity that run through the
world around us?
Simplicity in design was a lesson I fell into when
the Army drafted me -- after I'd finished college.
They assigned me to the Signal Corps Engineering
Labs and put me to work designing research
equipment. There I met a fine designer, Jules
Soled, a person who could clearly teach me things.
So I said to him, "Teach me, and I'll work for
you." He taught me many things I hadn't learned in
school, and his central lesson was always this:
Do a first design. Then attack it. Your first
design will be elegant and complicated, but it'll
always work better when you get rid of
complication. In a really good design you
eventually make the very design itself unnecessary.
And that is very hard to do because we like
complication.
That idea is really quite old. The towering
14th-century philosopher William of Occam put it
this way: "Multiplicity ought not to be posited
without necessity." William was telling us we
should make no more assumptions than we really need
to explain anything -- the simplest explanation is
best. We call that idea Occam's Razor because it
helps slice away the junk in our thinking.
Look at the safety razor. For years designers
fought with the problem of loading, mounting, and
unloading a blade in a holder. If you're old
enough, you'll remember Shick's "push-pull,
click-click" advertisement for its mechanism.
Keeping the action workable, and the blade solidly
in place, was a big problem.
Then some bright person applied Occam's razor to
the razor-mounting problem. That designer realized
you could simply mold the blade right into the
plastic packaging. Now who buys replaceable razor
blades? Instead, the blades are set, very solidly
and with great precision, right into a cheap
throwaway piece of plastic. We've designed
blade-holding mechanisms out of existence. That's
what Soled meant when he said that good design
makes the design itself unnecessary.
But to take that last step -- to walk the plank
from a clever design to no design at all -- takes
nerve as well as imagination. We're so tempted to
look smart by mastering complication instead of
simplicity. If we go back to our Shaker tune,
'Tis a gift to be simple, 'tis a gift to be
free;
the second line says:
'Tis a gift to come down where you ought to
be
Good design exacts a price from our egos, but it
really is a gift -- it really is freedom -- to find
the simplicity in things and finally to reduce an
engineering design down to where it ought to be.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
(Theme music)
