I know better than to attempt to write an april fools day post that really
tries to fool anyone. I’m not a good enough writer to carry that kind of thing off
in a genuinely amusing way. On the other hand, I love april fools day pranks, and
I generally like the silly mood of the day. So I thought I’d write some posts in
the spirit of silliness.
As someone working in engineering, one of my favorite rules is Murphy’s Law. The thing about Murphy’s law is that odds are, what you just thought when I said “Murphy’s Law” is not, in fact, Murphy’s Law. Odds are, you think that Murphy’s law says “If anything can go wrong, it will”. That’s not what it says – Murphy’s law is almost always stated wrong!
The real Murphy’s law: If there’s more than one way to do something,
and one way will result in disaster, then someone will do it that way.
The real Murphy’s Law probably wasn’t even actually created by anyone named Murphy. It dates back to some work done by Colonel John Stapp, a military scientist studying the effects of acceleration on human bodies.
According to the story, Stapp was working with a Major Edward Murphy
on acceleration sleds. The idea of the work was basically to set a sled on
a track, attach a rocket, stick a chair on top with a test subject (generally Colonel Stapp himself) sitting it in, and launch. A bunch of accelerometers were wired to the sled, so that you’d know just what a given experiment did to
the poor Colonel. (The image at the top of this post is a picture of Colonel
Stapp riding the sled during one of these experiments.)
In a famous error, on the first launch of a new, higher acceleration
version of the sled, all of the accelerometers on the sled were
wired backwards, meaning that the experiment provided no information – but Stapp walked away with broken ribs and a detached retina.
Someone – accounts differ as to whether it was Murphy, Stapp, or someone else
– who was talking about the technician who set up the accelerometers, said,
roughly, “If there’s more than one way to do it, and one of them will cause a
disaster, that’s the one that that guy will choose.” It’s most likely Stapp who
restated this as a general principle, and made it into a guiding principle in the
design of their later experiments and test apparatuses. Whoever said it first,
Stapp is clearly the one who popularized it: in press conferences, he told people
that the reason that there were so few serious injuries in their work, despite its
immense danger, was because “they always took Murphy’s law into
What I like about the real Murphy’s law in contrast to the popular one
is where it assigns the blame. The popular Murphy’s law basically says that
the universe itself is pathological – that it’s just the way the world works. The real Murphy’s law places the blame where it really belongs: given the opporunity, people will find a wind to screw things up.
Stapp later came up with another law, which is known as Stapp’s law, which makes that point even clearer: “The universal aptitude for ineptitude makes any human accomplishment an incredible miracle.”