Even before psychology became an experimental science in the 1890s, learning was an important part of it. But there came a time in the 1910s when psychologists started to become fascinated by learning concepts and learning theories. The 1930s and 1940s are sometimes called the golden age of learning theory; that was when learning was the heart and soul of psychology. And then gradually the gold began to lose its glitter. The theorists did not seem able to settle their differences of opinion, psychologists began to think that the differences were only a matter of opinion with little empirical significance, and there emerged a growing distaste for the great debates over fundamental issues. In the 1960s new procedures and new phenomena were discovered that led psychologists away from the basic issues that the learning theorists had debated. Learning remains an important part...