ABSTRACT
In these pages I share some thoughts about the lessons I learned during 40 years of work in the field of mental retardation. While my principal focus is on the direction the science has taken, a primary lesson is that science is not an isolated enterprise. Over the years, I observed the vicissitudes of American history as they affected the discipline. Looking back, I see that many of the issues and purported solutions emphasized at any particular time represent the swinging of the historical pendulum. The path and speed of the pendulum are directed not only by knowledge derived from the latest scientific research, but also by political, economic, and social forces that have little to do with mental retardation but have a profound impact on professional approaches to it.
