Continuity and Change in the Field of Cognitive Development and in the Perspectives of One Cognitive Developmentalist

In this article, I examine changes in the field of cognitive development and in my own thinking over the past 40 years. The review focuses on three periods. In the first, Piaget’s theory was dominant, and my research and that of many others was aimed at understanding the many fascinating changes in children’s thinking that Piaget documented, and correcting inaccuracies in his theory. In the second period, which involved efforts to formulate alternatives to Piaget’s approach, I generated overlapping waves theory, and attempted to specify through microgenetic methods and computer simulations how development can be produced by variability of strategy use, adaptive choices among strategies, and discovery of new strategies. In the third period, my thinking and research, and that of many others, has focused increasingly on the interface between cognitive development and education. I close by suggest that generating domain-specific integrated theories of cognitive development may provide a way forward for the field. KEYWORDS—cognitive development; numerical; math education; Piaget; overlapping waves Many happenstance events contributed to my decision to study cognitive development, but the choice was not totally fortuitous. For as long as I can remember, I have been fascinated by change—changes over eons of evolution, centuries of history, years of a human life, weeks of a football season, and seconds or minutes of a learning event. The basic questions are the same regardless of the time scale and domain: What set the changes in motion, what did and did not change, and what mechanisms underlay the changes and continuities? These were the fundamental questions when I entered the field, and they remain fundamental today. Once I decided to focus on psychology, it may have been inevitable that my interests would gravitate to child development. Although questions about change can be asked in any area of psychology, they are central to the study of development. A researcher who focuses on cognitive, social, or perceptual psychology might or might not be interested in change, but it would be a strange developmentalist indeed who was not interested in it. Moreover, children’s energy, candor, playfulness, and originality have always appealed to me. A rare privilege of working in developmental psychology is that thousands of colleagues in the field are similarly fascinated by children and change. That gives us a lot to talk about. A continuing theme of my research has been how children’s mathematical and scientific problem solving changes with age and particular experiences. However, the concepts and problem-solving skills that I have studied, and the theories and methods that I apply to them, have changed considerably. These continuities and changes reflect trends in the field as much as my own intellectual development. Robert S. Siegler, Carnegie Mellon University. The research reported in this article was supported in part by the Institute of Education Sciences, U.S. Department of Education, through grants R305A150262 and R324C100004:84.324C, Subaward 23149 to Carnegie Mellon University, in addition to the Teresa Heinz Chair at Carnegie Mellon University and the Siegler Center of Innovative Learning, Beijing Normal University. The opinions expressed are those of the author and do not represent views of the Institute or the U.S. Department of Education. Correspondence concerning this article should be addressed to Robert S. Siegler, Department of Psychology, Carnegie Mellon University, Pittsburgh, PA 15213; e-mail: [email protected].