Murphys Law

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Murphy's law ( English Murphy’s law ) is based on the American engineer Edward A. Murphy Jr. declining wisdom that makes a statement about human error or sources of error in complex systems .


Murphy's law reads:

"Anything that can go wrong will go wrong."

"Anything that can go wrong will go wrong."

It goes back to John W. Campbell Jr. (1910–1971) (see Finagle's Law ) and became known worldwide as Murphy's Law.

Engineer Captain Edward A. Murphy took part in the US Air Force's rocket sled program at a California test site in 1949 . The aim of the test was to find out what accelerations the human body can withstand. On the occasion of an expensive experiment , sixteen measuring sensors were attached to the test person's body. The sensors could be attached in two ways: in the correct position and at a 90 ° deviation from this. The experiment failed because someone incorrectly connected all the sensors. This experience led Murphy to formulate his law. The original version read:

"If there's more than one possible outcome of a job or task, and one of those outcomes will result in disaster or an undesirable consequence, then somebody will do it that way."

"If there are multiple ways to get a job done, and one of them ends in disaster or otherwise has undesirable consequences, someone will do just that."

A few days later Major John Paul Stapp quoted this at a press conference .

Natural and engineering scientists have primarily dealt with Murphy's law. It is used in modern technology as a heuristic standard or as empirical knowledge for error avoidance strategies (among other things in computer science and quality assurance - fail-safe principle, for example fail-safety through redundant systems), this puts the apparently funny "law" on a scientific one Base.

The reduced version of the law (everything that can go wrong will also go wrong) is also system-related, that is, it can only be applied to closed systems or experimental arrangements. As soon as it is applied to future or unfinished actions or processes, an increasing influence of factors (perceived as regulating) can be observed that shake the “law”, as Stefan Klein has proven, among others .

This manifests itself in daily life by the fact that the worst possible case often does not occur, but in these rare cases Murphy's law is reminded (see also cognitive bias ).

According to the author Ulf Heuner , Murphy's law has nothing to do with entropy , chance or probability, but with necessity. He cites as an example that if an old, crumbling house collapses, it does so according to the law of entropy and not Murphy's law. If a house collapses as soon as it is built, something has gone wrong. The paradox of Murphy's law is that people are very often responsible for things that go wrong, but also that certain factors that are not in the power of individual people ensure that something (necessarily) goes wrong at some point. As such factors, he makes z. B. uncontrollable actions of fellow human beings, unconscious acts of sabotage of our brain , our own, irrepressible will of our body or the treachery of the object . Under certain circumstances, all factors together could cause the "catastrophe".

Occasionally Murphy's Law is incorrectly attributed to the philosopher, theologian, and amateur psychologist Joseph Murphy , but his theory was:

"What one transmits to the unconscious as true becomes true."

Murphy's law is often satirized . These pastiche are similar to Murphy's Law, but they do not always have anything to do with it and are seldom meant seriously. A conciliatory addition to Murphy's Law reads: "[...] and you can always find someone who can fix it."

A reversal of Murphy's law is found in Yhprum's law .


  • Robert Matthews of Aston University in Birmingham was awarded the Ig Nobel Prize in 1996 for his studies of Murphy's Law, particularly for showing that slices of toast have an inherent tendency to fall on the buttered side .
  • The concept of the trick series Worse Always Goes With Milo Murphy (English original title Milo Murphy's Law ) is Murphy's law. The main character Milo is trained as a descendant of Murphys.

See also


  • Arthur Bloch: Collected reasons why everything goes wrong, what can go wrong! Wilhelm Goldmann, Munich 1985, ISBN 978-3-442-10046-0 .
  • Peter Helling, Bernhard Spengler, Thomas Springer: Errors planned correctly . Verlag Bau und Technik, Erkrath 1987, ISBN 3-7640-0232-8 .
  • Joachim Graf: Murphy's computer laws . Market and technology, Haar near Munich 1990, ISBN 3-89090-949-3 .
  • Joachim Graf: Murphy's meanest computer laws . Market and technology, Haar near Munich 1998 ISBN 3-8272-9032-5 .
  • Stefan Klein: It was all coincidence . Rowohlt, Reinbek near Hamburg 2005, ISBN 978-3-499-61596-2 .
  • Ulf Heuner: Mistakes, breakdowns, mishaps. The first survival book . Klett-Cotta, Stuttgart 2007, ISBN 978-3-608-94447-1 .
  • Paul Watzlawick Guide to Unhappiness . Piper, Munich 2009, ISBN 978-3-492-24938-6 .

Individual evidence

  1. ^ Reto U. Schneider : The great brakeman . In: Spiegel . May 2006, p. 89.
  2. ^ Robert Matthews: Tumbling toast, Murphy's Law and the fundamental constants . In: European Journal of Physics . Volume 16, No. 4, July 18, 1995, pp. 172-176.

Web links

Wiktionary: Murphy's Law  - explanations of meanings, word origins, synonyms, translations