Trial and error

Trial and error

Trial and error, or trial by error, is a general method of problem solving for obtaining knowledge, both propositional knowledge and know-how. In the field of computer science, the method is called generate and test. In elementary algebra, when solving equations, it is "guess and check".

This approach can be seen as one of the two basic approaches to problem solving and is contrasted with an approach using insight and theory.


Bricolage -In trial and error, one selects a possible answer, applies it to the problem and, if it is not successful, selects (or generates) another possibility that is subsequently tried. The process ends when a possibility yields a solution.

In some versions of trial and error, the option that is a priori viewed as the most likely one should be tried first, followed by the next most likely, and so on until a solution is found, or all the options are exhausted. In other versions, options are simply tried at random.


This approach is more successful with simple problems and in games, and is often resorted to when no apparent rule applies. This does not mean that the approach need be careless, for an individual can be methodical in manipulating the variables in an attempt to sort through possibilities that may result in success. Nevertheless, this method is often used by people who have little knowledge in the problem area.


Trial and error has a number of features:
* solution-oriented: trial and error makes no attempt to discover "why" a solution works, merely that it "is" a solution.
* problem-specific: trial and error makes no attempt to generalise a solution to other problems.
* non-optimal: trial and error is an attempt to find "a" solution, not "all" solutions, and not the "best" solution.
* needs little knowledge: trials and error can proceed where there is little or no knowledge of the subject.


Trial and error has traditionally been the main method of finding new drugs, such as antibiotics. Chemists simply try chemicals at random until they find one with the desired effect.

The scientific method can be regarded as containing an element of trial and error in its formulation and testing of hypotheses. Also compare genetic algorithms, simulated annealing and reinforcement learning - all varieties for search which apply the basic idea of trial and error.

Biological evolution is also a form of trial and error. Random mutations and sexual genetic variations can be viewed as trials and poor reproductive fitness as the error. Thus after a long time 'knowledge' of well-adapted genomes accumulates simply by virtue of them being "able" to reproduce.

Bogosort can be viewed as a trial and error approach to sorting a list.

In mathematics, the method of trial and error can be used to solve formulae - it is a slower, less precise method than algebra, but is easier to understand.

ee also

* Brute force attack
* Brute-force search
* Empiricism


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • trial and error — ► a way of achieving something or solving a problem by trying a number of different methods and learning from the mistakes you make: »Although some products quality can be verified through trial and error, this is not always practical. → See also …   Financial and business terms

  • trial and error — ri al and er ror The method of discovering something desirable by trying many different things until one works; as, the traditional method of finding new drugs is by trial and error. [PJC] And millions miss for one that hits. Swift. [1913… …   The Collaborative International Dictionary of English

  • trial and error — n. the process of making repeated trials or tests, improving the methods used in the light of errors made, until the right result is found trial and error adj …   English World dictionary

  • trial and error — ► trial and error the process of experimenting with various methods until one finds the most successful. Main Entry: ↑trial …   English terms dictionary

  • trial and error — trial and error, adj. experimentation or investigation in which various methods or means are tried and faulty ones eliminated in order to find the correct solution or to achieve the desired result or effect. [1800 10] * * * …   Universalium

  • trial and error — noun experimenting until a solution is found (Freq. 2) • Hypernyms: ↑experiment, ↑experimentation * * * noun : a finding out of the best way to reach a desired result or a correct solution by trying out one or more ways or means and by noting and …   Useful english dictionary

  • Trial and Error — Tri|al and Er|ror 〈[traıəl ənd ɛ̣rə(r)] n.; ; unz.; Päd.; Verhaltensforschung〉 Methode der Problemlösung u. des Lernens, bei der eine Aufgabe nicht durch strategische Vorüberlegung, sondern durch wiederholtes Ausprobieren verschiedener… …   Universal-Lexikon

  • trial-and-error — adjective 1. trying out various means or theories until error is satisfactorily reduced or eliminated he argued that all learning is a trial and error process that resembles biological evolution • Similar to: ↑empirical, ↑empiric 2. relating to… …   Useful english dictionary

  • trial and error —    Attempting to achieve a satisfactory result by testing and eliminating various methods until the best one is found is called trial and error.     Some of the best cooks learn by trial and error …   English Idioms & idiomatic expressions

  • trial and error — {n.} A way of solving problems by trying different possible solutions until you find one that works. * /John found the short circuit by trial and error./ * /The only way Tom could solve the algebra problem was by the method of trial and error./ …   Dictionary of American idioms