Thorndike's theory of learning, also known as the law of effect, states that behavior that is followed by a positive consequence is more likely to be repeated, while behavior that is followed by a negative consequence is less likely to be repeated.

Based on Thorndike, learning is phenomenon that grows associations between one events to another events which is called as stimulus (S) with respond (R). Stimulus is a changing of external environment that become sign to activate organism to react and act. And, respond is behavior that is raised by stimulus.

Thorndike's theory was an association theory, as many were in that time. He believed that the association between stimulus and response was solidified by a reward or confirmation. He also thought that motivation was an important factor in learning.

Connectionism is the philosophy of Edward Thorndike, which says that learning is a product between stimulus and response. A stimulus is something that causes a reaction, while a response is the reaction to a stimulus. The connection between the two is called an S-R bond, or stimulus-response bond.