Roger Shepard

Hovland Lecturer, Yale University, 2000

The Hovland Lecture was established to remember an intellectual giant who studied and taught at Yale from 1933 to 1961.

Carl Hovland trained here with the eminent learning theorist Clark Hull, providing in his dissertation the first evidence for a law of generalization. His professional career was marked by meteoric success. In his first year in graduate school he prepared six papers for publication, went rapidly from being an instructor to a young chair of the department and Director of the Laboratory of Psychology at age 33, to Sterling Professor at age 36, an honor he refused to accept in advance of his advisor Clark Hull. He was not just (as my young neighbor Ricky would say), wicked smart, he was also wicked good.

Hovland brought his work on learning and generalization to bear on problems of communication and attitude change, and published (with others) the influential 1949 book Experiments in Mass Communication . Under his leadership, the Yale Communication and Attitude Change Program shaped the course of social psychology here and everywhere.

The facts I've presented about Carl Hovland come from a short biography written by Roger Shepard in the Biographical Memoirs published by the National Academy of Sciences.

The Hovland lectureship was established in the early 1960's, with Bill McGuire, also a student of Carl Hovland's being the first speaker. Over the past 30 or so years, many remarkable scientists have visited as Hovland lecturers: Elliot Aronson, Amos Tversky, Dick Nisbett, Lee Ross, Herb Simon, Robyn Dawes, and Bob Zajonc are among them. It's easy to see why I'm proud to have been a trustee of this lectureship.

Today, I introduce to you, a jewel of a scientist, a student of Carl Hovland's, the incomparable Roger Shepard.

Long before the era of Harry Potter, I had described Roger Shepard as a wizard -- of the mind. And if indeed he is as I say, then Yale must surely be Hogwarts, for this is where it all began. Roger studied with Carl Hovland, receiving his Ph.D. from this university in 1955. When he entered psychology in mid-century, the dominant paradigm was quite clear: a science of psychology had to be built on the study of observable behaviors that could be quantified in physical units. Mental states such as perception and memory were assumed to be accessible only through verbal self-report and therefore as outside the reach of objective verification. Roger Shepard's life's work showed this dominant view to be fundamentally false.

At Bell Laboratories where he worked for the first several years of his career, he developed the very first methods of nonmetric multidimensional scaling, a technique that allowed the conversion of qualitative information about symmetry, association, and correlation into quantitative distances in an abstract representational space. In a person of even high talent this accomplishment alone would have been a sufficient basis for a claim to greatness. For Roger it was the first of many fundamental contributions, accomplished over a 30 year period, first at Harvard and then Stanford.

Among these accomplishments, I single out one because I remember my own audible gasp when I first discovered his demonstration of the analog character of mental rotation, not just for the discovery alone, but for the sheer elegance of the logic and the method that revealed it.

Shepard's contribution to the cognitive revolution came in the form of proposals that showed that fundamental psychological principles have arisen as adaptations to universal features of the world. For having made a compelling connection between the physical and the mental, Roger Shepard's work is firmly in our history books not only because it is great work, but also because it is always the first great work.

Today, I think he is going to tell us about other firsts: Archemedes, Galileo, Newton, Einstein, and how it is that physical laws about the universe are no more real than the laws that govern the minds that produced these laws.

Roger Shepard's many honors and recognitions include the APA's Distinguished Scientific Contribution Award in 1976, membership in the National Academy of Sciences since 1977, the Warren Medal of the Society of Experimental Psychologists in 1981, William James Fellow of the APS since its inception, the National Medal of Science in 1995 and the Gold Medal for Life Achievement in the Science of Psychology from APA this year.

Roger, we rejoice in your accomplishments. Carl Hovland would no doubt have rejoiced as well. Thank you for speaking to us about the cognitive grounds of science ethics. Welcome back to your university!