What is the “law of effect?” What are some examples of this law?

What is the “law of effect?” What are some examples of this law?

Edward Thorndike’s Law of Effect

Edward Thorndike constructed the ‘law of effect’ which states, “…that responses that produce a satisfying or pleasant state of affairs in a particular situation are more likely to occur again in a similar situation. Conversely, responses that produce a discomforting, annoying or unpleasant effect are less likely to occur again in the situation” (Thorndike, 1911).

Thorndike’s S-R theory uses a cat learning example in which the animal must escape a “puzzle box” by pressing a lever. The cat accomplishes this task and learns by associating the action of pressing the lever (S) with the door's opening (R). The S-R connection is made by escaping from the box and now occurs more frequently when the the cat is in the box (Thorndike, 1911).

Readily seen examples can be seen as anything pleasurable or satisfying resulting in repeated actions. For instance, rewarding employees with praise for task completion, they are more likely to complete more tasks. The opposite is true if an employee is admonished for not completing a project. The law of effect is a key component in psychological theory with regard to motivation.


Thorndike, E. L. (1911). Animal intelligence: Experimental studies. New York : Macmillan. Retrieved June 16, 2010, from 

Article Updated: 11/03/2021

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