Thorndike’s Law concerns the role of reward in learning. It is known as the Law of Effect, because whether a response would be stamped in or stamped out depends upon the effect such a response produces. If a response produces ‘satisfaction’, it will be strengthened, and is more likely to be repeated in the same situation. On the other hand, if a response produces ‘discomfort’ or ‘annoyance’ it will be weakened and is less likely to reappear. The greater the satisfaction, the greater the strengthening of the response. Similarly, the greater the discomfort, the greater the weakening of the response.

Thorndike explains the term ‘satisfaction’ and ‘discomfort’ in the following way. A state of affairs is said to bring satisfaction, if the organism does nothing to avoid it, but tends to attain and preserve it. A state of affairs is said to bring ‘discomfort’ or ‘annoyance’, if the organism tends to avoid it, and does nothing to preserve it. A satisfier is one, which the animal likes to obtain; a discomforted is one, which the animal likes to avoid.

Many forms of human learning also obey the Law of Effect. When a child shows behavior to the satisfaction of his parents, they approve of it. Parental approval serves as a reward for the child and gives him satisfaction. As a result, the child tends to repeat the same behavior on a later occasion. On the other hand, if a particular behavior of the child is disproved, it gradually weakens. The child tends not to repeat the same behavior again.

In Thorndike’s experiment, the response of pulling the loop brought satisfaction to the animal. This response was strengthened and was repeated time and again. On the other hand, the random responses like clawing and biting brought discomfort and were weakened. The correct response appeared again and again while wrong responses gradually reduced, and finally disappeared.


The original form of the Law of Effect was known as the Symmetrical Law of Effect, because it proposed that the positive and the negative consequences are equal but opposite in their effects. But Thorndike’s further research convinced him that discomforting affairs do not directly weaken the S-R connection. As a result, in 1932 he had to abandon the second half of the Law of Effect. This modified version was known as the truncated Law of Effect. Thorndike still maintained that punishment carries some indirect value in the sense that it causes ‘shift to right behavior’ for which there is a reward. For example, when parents punish the TV-watching behavior of children, the response of TV-watching is not weakened; it is only suppressed for a while, and is likely to reappear when parents are absent.

Criticism of Law of Effect:

The Law of effect was also criticized on other grounds. All along, Thorndike’s emphasis was on response connections, but he used terms like ‘satisfaction’ and ‘annoyance’, which only denote mental, states, and are subjective. Secondly, how can the Law of Effect work in a backward manner? The response is rewarded only after it is executed. How can the reward go backward in its effect and strengthen responses that precede it. Finally, how do we know which are ‘satisfiers’ or ‘annoyers’? It will be identified as a satisfier, if it strengthens the response. Then the question is – How is a response strengthened? A response is strengthened if it is followed by a satisfier. As you-may notice, Thorndike’s explanation is circular in nature.