Murphy’s Law is a humorous American axiom that states anything that can go wrong, will go wrong. The term Murphy’s Law was coined in the early 1950s during G-force tests by the American Air Force. One version of the story says that an aerospace engineer named Captain Edward A. Murphy installed a key sensor backwards, skewing the test results. Another version of the story states that Captain Murphy did no such thing, that the reason he is associated with Murphy’s Law is that he frequently expressed the idea that anything that can go wrong will go wrong. Eventually, other members of the team began to refer to this sentiment as Murphy’s Law. A third version of the story comes from John Glenn, stating that Murphy was a character in Navy educational cartoons cast as an incompetent mechanic, leading to the idea of Murphy’s Law. Murphy’s Law is by far the most popular of the humorous laws dealing with things that go wrong.
Sod’s Law is a British axiom that is somewhat similar to Murphy’s Law, but with a twist. Sod’s Law carries a sense of being mocked by fate. Sod’s Law is related to the idea of the unlucky sod, an average person who has bad luck. Sod’s Law first appears in the 1970s.
Finagle’s Law is Murphy’s Law with an addendum, it states that anything that can go wrong will, and at the worst possible time. The term Finagle’s Law was coined by John Campbell Jr., the editor of Astounding Science Fiction in the 1940s through 1960s.
Part of Murphy’s Law states that everything will take longer than you think. (The Business Journals)
Considering Labor is eyeing off 10 seats in the always-volatile Queensland, where a swing can turn into an avalanche, and that Murphy’s Law – what can go wrong will go wrong – often rules in campaigns in the most unexpected areas, the Coalition was understandably edgy. (The Sydney Morning Herald)
“It’s sod’s law that it is not there when you need it to be.” (The Bury Times)
The belief in so-called sod’s law, displaying a negative outlook on fate, can be traced far back into human history. (The Daily Mail)
It is also known as Finagle’s Law of Negative Dynamics or Finagle’s corollary to Murphy’s Law. (American Thinker)