One of the pioneers in the field of cognitive psychology was the German psychologist Hermann Ebbinghaus (1850–1909), whose experiments helped establish memory capacity limits and provided an early foundation for modern theories of learning and forgetting. While his work had little influence during his lifetime, his findings became widely accepted only after World War II, when they were rediscovered by the American psychologists George A. Miller and Elizabeth J. Spelke. His methods, however, were less regarded.
Although he was meticulous about organizing his research and following a rigid set of rules, Ebbinghaus did not involve any living human being in his work. He believed that thinking processes were best understood through self-observation. Since we can’t observe our own thoughts directly, however, he thought that the best place to study those thoughts would be inside the head of another person. Other researchers saw these methods as unreliable because they involved observing someone else’s behavior instead of their own, and so devised other ways to study cognition on other subjects.
