Law of the Instrument

from Wikipedia, the free encyclopedia

The Law of the Instrument ( English for "Law of the Instrument"; also: " Maslow's Hammer ") describes the observation that people who are well acquainted with a tool (or a procedure) tend to use this tool even then use when another tool would be more suitable. This excessive use of a tool for which the user has developed a preference - possibly not justified in factual terms - is often based on the mistake of thinking that an approach which has been successful in the past will also be successful in all other cases in the future .


The quote “If you only have a hammer as a tool, you will see a nail in every problem” is often attributed to the American writer Mark Twain , but there is no evidence of this in his work. Even Paul Watzlawick is wrongly named as the author.

It can be attributed occupied on the psychologist Abraham Maslow , who wrote in 1966: "I think it's tempting when the only tool you have, is a hammer, to treat everything as if it were a nail." Already in in february 1962, however, the philosopher had Abraham Kaplan in a presentation at a conference of the American Educational Research Association said: "Give a boy a hammer, and must hit on all that he comes under" . The psychologist Silvan Tomkins made a similar statement in 1963: "When you have a hammer, you tend to look for nails" .

Areas in which the action of the Law of the instrument has been repeatedly described include the financial market (“ Baruch 's Observation”) and medicine, the latter for example in the 1960s, when only two were used in the USA for the treatment of psychoses Medicines were available - trifluoperazine and chlorpromazine - which were often used even when the diagnosis of schizophrenia was in doubt; This abuse is discussed u. a. in the feature film One Flew Over the Cuckoo's Nest . The universal application of mercury preparations or bloodletting in the Middle Ages and in the early modern period can be understood in a similar way.

See also


  • Charles C. Doyle, Wolfgang Mieder, Fred Shapiro (compilation): The Dictionary of Modern Proverbs . Yale University Press, 2012, ISBN 978-0-300-13602-9 ( limited preview in Google Book Search).

Individual evidence

  1. ^ Abraham H. Maslow: The Psychology of Science: A Reconnaissance , p. 15
  2. If Your Only Tool Is a Hammer Then Every Problem Looks Like a Nail ,, May 8, 2014