PETER WASON was one of the most creative and influential British psychologists of the post-war era.
He challenged the orthodox view of his time that people were by nature basically rational and logical, demonstrating, by the ingenious construction of novel experimental tasks, a range of what are now known as "cognitive biases". In so doing, he laid the foundations for the modern study of thinking and reasoning, which has become a major international research field. In contrast with most fields of cognitive psychology, the study of this topic is not dominated by American researchers. It is part of Wason's legacy that, to this day, British and European researchers take the lead in the study of human reasoning.
Wason was born in Bath in 1924. After a childhood - by his own account - of "failing school exams with monotonous regularity" and then officer training at Sandhurst, he became a liaison officer in the 8th Independent Armoured Brigade and was injured in Normandy in 1945. He read English at New College, Oxford, where he met his future wife Marjorie Salberg.
In 1950, he decided to start again by reading for a degree in Psychology at University College London. He was to stay at UCL for the rest of his academic career. Following his PhD and a period of work as a research fellow, in 1970 he was appointed to the position of Reader in Psycholinguistics, which he held until his retirement in 1982.
Wason's love of English and English literature had an impact on this work in psychology in several ways, and in the later part of his career he undertook research into the psychology of writing. He was extremely interested in the art of writing, and took great pains to impose the highest standards on his PhD students. He wrote with great clarity and conviction in his own publications, and this is one of the major causes of his influence. However, he could be as hard on himself as on his students. On one occasion he wrote several drafts of an entire book before abandoning it, as he was not satisfied with the final product. His other great passion was chess, which he played only by correspondence - but to a very high standard - eventually achieving the standing of International Master in this form of play.
Wason published most of his psychological work over a 25-year period from the late 1950s up to the early 1980s. Of these publications, probably the most influential was the book Psychology of Reasoning: structure and content (1972; co- authored by P.N. Johnson-Laird). This book was focused almost entirely on the work of Wason and his collaborators at UCL over the previous 15 years - but then that was mostly what the psychology of reasoning consisted of at that time. This work developed several new tasks and paradigms for the study of reasoning that are heavily used to this day, as well as founding a British tradition in the study of cognitive biases. In this context, the term "bias" refers to the tendency of people to err in systematic ways relative to a logical analysis of the problems they are set.
Wason's work was influenced by two academic giants of his period, the philosopher Karl Popper and the great Swiss psychologist Jean Piaget. Popper had devised a highly influential philosophy of science that founded the doctrine of falsificationism. …