What Is Murphy’s Law?

On the day of the most important interview of your life, you discover that every good tie is still in the laundry, it rains as it never has and never will again, the cabs taunt you as they race by and when you reach the office two hours late, not only have you arrived at the wrong building, but you’re also not wearing any pants. The worst possible outcome is achieved, or as Capt. Edward Murphy once remarked: “If that guy has any way of making a mistake, he will.” The adage has since been called Murphy’s Law.

The Law of Large Numbers

Murphy’s law can be condensed to Anything that can possibly go wrong, does. While the “law” is thought of as more of an aphorism, mathematicians know that it is grounded not only in belief, but also in fact. It is a matter of chance or probability.

Let’s say that each of the five unfortunate events that occurred on the day of your interview can occur with a probability of 1/100. When we wish to determine the probability with which all the events will occur simultaneously, we multiply all the individual probabilities with each other. The multiplication implements the AND operation, implying that Events 1, 2, 3, 4 AND 5 occur together.

For the five events, the probability of their simultaneous occurrence is 1/10,000,000,000. To say the chances are bleak would be an understatement, for it would occur only once in 10 billion interviews! However, the event would then occur 10 billion times in 100 billion billion interviews. When we increase the sample size or trials exponentially, the probability of the occurrence of an extremely rare event also increases, such that it ceases to be rare anymore.

Now, the generalization seems farcical, for the events are not so evenly distributed, but the implication remains the same. In the grand scheme of things, the vacillating occurrences converge at a single mean. This was first suggested by Augustus De Morgan in 1866, so perhaps the law should’ve been named after De Morgan, rather than Murphy.

While the law incites pessimism, one must not abandon optimism. The convergence is equally true for both unfortunate and fortunate events, which led us to coin Yhpurm’s law: Anything that can go right, will go right.

Image result for elmo explosion

It’s all about perspective.


Edward Murphy and his fellow engineers wished to test the human tolerance for the effects of sudden deceleration during a car crash, but the test failed miserably. The test had failed because all the sensors were wired incorrectly. Murphy grew infuriated and immediately blamed his technical assistant, uttering, in a fit of arrogance, the statement he is now so renowned for. An engineer wrote the statement in his notebook and called it “Murphy’s Law”.

Whether this account is true is still a matter of debate, but the law is nonetheless highly pertinent to everything we do. Sailors often fear that anything that can go wrong at sea, will go wrong… sooner or later. Magician Nevil Maskelyne and humorist Paul Jennings went so far as to attribute the accidents not just to misfortune, hurry or worry but to “spiteful” objects conspiring against us or “exhibiting malice towards us”.

Didnt understand the fortune from my fortune cookie until i spent two hours shitting my brains night

(Photo Credit : memeguy.com)

Psychologists, of course, find anthropomorphizing objects to be ridiculous. To them, it highlights our biases, particularly confirmation bias, which is the bias to seek evidence that only confirms our beliefs and to neglect evidence that contradicts it. What compounds it is our negativity bias: we tend to notice and recall negative events with more accuracy than we recall the positive ones. Luck plays a crucial role in everything we do, but we seem to notice its significance only when it doesn’t favor us, like my brother blocking the television just when Steph Curry decides to attempt a last-second 3-pointer.

If the premonitions or pessimism have done any good, it is that it has made us excessively prudent. It would be foolish to develop, say, a nuclear reactor without meticulously investigating and ensuring that every possible way the reactor can turn into a time-bomb is averted before construction begins. Some believe that achieving absolute safety is impossible; they believe that errors are destined to seep in, but we can respond by citing Weiler’s law: nothing is impossible for the man who doesn’t have to do it himself.


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About the Author:

Akash Peshin is an Electronic Engineer from the University of Mumbai, India and a science writer at ScienceABC. Enamored with science ever since discovering a picture book about Saturn at the age of 7, he believes that what fundamentally fuels this passion is his curiosity and appetite for wonder.

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