You finally got the weekend off and decided to go on a family picnic, only for it to rain. You speed up past a slow driver, but you’re immediately greeted by a police officer. You lather your hair in the shower, and at that precise moment, the hot water turns off.

Congratulations, you’ve just had a taste of Murphy’s infamous law, which can be summed up by the phrase “Whatever can go wrong, will go wrong”. A more damning version of Murphy’s Law states “If anything can possibly go wrong, it will, and at the worst possible time.”

But is Murphy’s law actually true or is it just the product of our human mind biased towards pessimism? Let’s dive right in.

Where did Murphy’s Law come from? Yes, there really was a Murphy.

It was the year 1949 and just two years prior, a Bell X-1 rocket-powered research plane became the first aircraft to fly at supersonic speeds. At the Edwards Air Force Base in California, engineers knew they could go even faster. Certainly, it was technologically feasible to fly aircraft at multiples of the speed of sound but one bottleneck nevertheless gave them headaches: the human body.

In order to see just how much G-force, a measure of acceleration or deceleration, a human can withstand before blacking out, Air Force researchers started project MX981.

The mission involved a series of tests in which human pilots would ride a rocket sled, aptly dubbed “Gee Whiz”, to simulate the kind of G-forces experienced in a jet fighter by sudden deceleration. Brave test subjects hopped onto a rocket-propelled platform on rails, which traveled more than 200 miles per hour down a short track, before abruptly coming to a full stop in less than a second.

Colonel John Paul Stapp, a physician at the Air Force, was one of the volunteers who went through many such grueling rides. The brave test subject suffered many concussions, broken blood vessels in his eyes, and even broke some bones, all in the name of science so pilots may fly safely in the field.

Each rocket sled test had to pass its own battery of safety checks, and one of the key people responsible for these checks was an Air Force captain and reliability engineer by the name of Edward A. Murphy, Jr.

From this point onward, the details of the story tend to diverge depending on the source, but a common thread is that one day Murphy tried to install a set of sensors to the harness that held Dr. Stapp to the rocket. These sensors were designed to measure the exact amount of G-force experienced by the test subject.

However, during the first test run, the sensors produced a reading of zero, while Stapp’s battered face spoke otherwise. Upon closer inspection, Murphy found that all 16 gauges had malfunctioned because they were connected incorrectly. There were only two ways of connecting the sensors, and each one had been installed in the wrong way.

Murphy blamed the mistake on his technician, grumbling something along the lines of “If there’s any way they can do it wrong, they will.”

Not long after the incident, Murphy returned to Wright Airfield where he was stationed since he was transferred at Edwards temporarily for this specific job. But Murphy’s quirky remark stuck with Stapp, a man famous for his sense of humor and quick wit, recognizing its universal appeal.

Stapp’s efforts and sacrifices did not go unnoticed, being the subject of numerous news reports. So it happened that during a fateful press conference, one of the reporters asked the flight surgeon about the dangers of MX981, to which Stapp replied that he was confident in the project’s safety thanks to the team’s awareness of what he called Murphy’s Law.

Explaining what he meant by that, Stapp said “Whatever can go wrong, will go wrong”.

It didn’t take long for the phrase to be picked up by aerospace publications, then radio and television, and before you knew it, Murphy’s Law became ingrained into popular culture.

Is Murphy’s Law real?

Murphy’s Law isn’t really a ‘law’, not in the sense that we use the term in science, meaning a statement about an observed phenomenon or a unifying concept that is supported by a large body of empirical evidence.

Instead, it should be seen as a maxim: things can go wrong and they often do. No further explanation is required because we’ve all tasted the perverse nature of Murphy’s law on multiple occasions.

Besides, only a fool would try to prove or, heaven forbid, disprove Murphy’s Law. Washing your car to make it rain doesn’t work and, at the same time, doesn’t disprove Murphy’s Law.

“Murphy’s Law cannot be proven, yet is correct, as when you try to prove Murphy’s Law, you will see that the proof is incorrect. This is obviously due to Murphy’s Law, therefore Murphy’s Law is correct and proven.”

But even though Murphy’s Law is supposed to be treated with humor, the statement is actually rooted in hard science, echoing the second law of thermodynamics, which deals with the concept of entropy.

Simply put, entropy is a measure of the disorder of a system and the second law of thermodynamics states that “entropy must always increase in the universe and any hypothetical isolated system within it.” A system can mean anything: a galaxy, the economy of a country, a house, even the human body.

The second law of thermodynamics predicts that, left to themselves (i.e. without external energy input), systems tend to become more disordered. That’s not to say that your toast falls off the counter butter-side down every time because of entropy, but the fact that there are remarkable similarities between the two laws reminds us that all things around us are vulnerable to catastrophic failure.

Cars break down when heading to an important meeting or the weather is bad during the weekend because things like this are just bound to happen at some point — and when your day is ruined by a series of failures that look like the universe is plotting against you, it may just be your mind playing tricks on you.

Humans are riddled with cognitive biases, and it is an established fact that we tend to be more mindful of negative experiences compared to positive ones since such thinking has helped us improve survivability in the past.

For instance, due to selection bias, we tend to remember ‘bad stuff’ that happens to us more often than the good kind. Then there’s the matter of being aware of Murphy’s Law in the first place — due to confirmation bias, when something does eventually go wrong, we quickly point the finger — Aha, here’s Murphy at it again!

But even though Murphy’s Law can be explained by our flawed psyche, there may actually be some merit to the popular wisdom, in that things may indeed go wrong more often than they go as planned. One factor I mentioned earlier is entropy, but there may be more to it. For instance, some things that look random aren’t random at all, since certain outcomes are more statistically likely than others.

People have taken Murphy’s principle and noticed it has niche ramifications. In a 1997 article in Scientific American, Robert A. J. Matthews explains why we suffer from Murphy’s Law of Queues (the line next to you will usually finish first).

Although all queues should progress at more or less the same average rate — each line has the same probability of suffering from random delays — but when we visit the supermarket we aren’t dealing with global averages over time.

Matthews goes on to explain that the chance that we’ve picked the queue that will suffer from the least delays is 1/N, where N is the total number of queues in the supermarket. Even if we were concerned only about beating the queues on either side, two-thirds of the time either the line of the left or the one on the right will beat us to it.

Murphy’s Law: the precautionary principle and risk management

Dr. Stapp may have been inclined to share Murphy’s Law for a very simple reason: it probably saved his life. Turns out, Murphy’s Law is a fantastic design principle in engineering and any other field where a single failure can have catastrophic consequences. Take, for instance, NASA.

Each of its ambitious missions usually takes years to prepare and billions of dollars to fund, but all of that hard work can be unraveled in a single instant, and there many such opportunities from a rocket launch failure to an electronics glitch that might prevent a Mars rover from communicating with Earth, rendering the mission useless. This is why we have backup systems and backup-backup systems. The riskier the project, the more fail-safes it needs, and even then you’re not safe from Murphy’s Law.

Murphy’s initial maxim “Whatever can go wrong, will go wrong” can be interpreted less fatalistically as “If it can happen, it will”. Meaning, given enough time and exposure, even the least likely scenarios are bound to occur. This fact is well known to insurance brokers and risk management experts who have devised complex systems to assess risk and mitigate it accordingly.

Thanks to this disaster-minded approach many lives have been saved by designing airplanes and nuclear power plants with the thought that the entire universe is conspiring against us every day. It’s not the healthiest life attitude, but it serves its purpose.

Also, it’s worth bearing in mind that Murphy’s Law should only become more valid over time. That’s because it’s universally accepted that the more complicated a system is, the more likely it is to break down.

Today, we’re surrounded by increasingly complex machines that are often interdependent and connected using networks such as the internet. The complexity of 21st-century life is inviting Murphy’s Law to visit us more often than ever before.

Alternative versions to Murphy’s Law

To conclude, here are some interesting alternative versions of Murphy’s Law that speak universal ‘truths’:

• You never find a lost article (i.e. keys or socks) until you replace it.
• Smile. Tomorrow will be worse.
• Enough research will tend to support your theory.
• The opulence of the front office decor varies inversely with the fundamental solvency of the firm.
• Tell a man there are 300 billion stars in the universe and he’ll believe you. Tell him a bench has wet paint on it and he’ll have to touch it to be sure.
• Things get worse under pressure.
• If you perceive that there are four possible ways in which a procedure can go wrong, and circumvent these, then a fifth way, unprepared for, will promptly develop.
• If everything seems to be going well, you have obviously overlooked something.
• It is impossible to make anything foolproof because fools are so ingenious.
• Every solution breeds new problems.
• If anything can’t go wrong on its own, someone will make it go wrong.
• Nature always sides with hidden flaws.
• Mother nature is a bitch.

FAQ about Murphy’s Law