Murphy's Law

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If you are looking for other laws, see our longer Eponymous laws

Murphy's law states that if something can go wrong, then it will go wrong.

Murphy's law has two corrollaries: First, that if it can go wrong, it will go wrong at the worst possible time. Second, if there is a possibility of several things going wrong, the one that will cause the most damage will be the one to go wrong.

Murphy's law has one exception: Something will never go wrong when you want something to go wrong (though, recursively, this is Murphy's law). (Also known as the Law of Murphological Inapplicability.)


Murphy's law is attributed to a Captain Murphy. Dr. Stapp was an Air Force medical researcher who rode various extremely fast vehicles in order to test how much acceleration the human body can take. In one test, his assistant, Capt. Murphy, had designed a harness to strap in the rider that held 16 sensors to measure the acceleration on different body parts. There were exactly two ways each sensor could be installed. Murphy did each one wrong. When Dr. Stapp staggered off the sled with bloodshot eyes and bleeding sores, all registered zero. A distraught Captain Murphy proclaimed: If there are two or more ways to do something and one of those results in a catastrophe, then someone will do it that way.[1]


  • When waiting for a bus, every other bus will show and just when you get sick and tired of it all and light a cigarette[note 1], your bus will arrive. You may instead choose to take a cab/taxi, at which your bus will pass by you minutes after you have entered your cab.
  • Your computer will tend to crash when you have a long, unsaved edit of significant importance. The hard drive in said computer will tend to corrupt during that crash when the autosave of said document is stored locally.
  • When drinking quietly and secretively while your girlfriend is out with friends, you'll get to the point wherein you only have one beer left but you don't want to open it because you don't want to appear to be drinking when she arrives. After an hour and she hasn't arrived you open it, thinking all is calm, and then she walks in the door and accuses you of being drunk.
  • In the UK, it always rains on bank holidays.[3]
  • A valuable dropped item will always fall into an inaccessible place (a diamond ring down the drain, for example) — or into the garbage disposal while it is running.


  1. Only applicable in areas where buses are smoke-free.