Peter Cathcart Wason was a cognitive psychologist

Cognitive psychology

Cognitive psychology is a subdiscipline of psychology exploring internal mental processes.It is the study of how people perceive, remember, think, speak, and solve problems.Cognitive psychology differs from previous psychological approaches in two key ways....

, who worked on the psychology of reason. He made great progress in explaining why people make certain consistent mistakes in logical reasoning. He designed logical problems and tests to demonstrate these processes, for example the Wason selection task

Wason selection task

Devised in 1966 by Peter Cathcart Wason, the Wason selection task, one of the most famous tasks in the psychology of reasoning, is a logic puzzle which is formally equivalent to the following question:...

, the THOG problem

THOG problem

The THOG problem is one of Peter Wason's logic puzzles, constructed to show some of the weaknesses in human thinking.You are shown four symbols#a black square#a white square#a black circle#a white circle...

 and the 2-4-6 problem.

Wason was an International Master in correspondence chess

Correspondence chess

Correspondence chess is chess played by various forms of long-distance correspondence, usually through a correspondence chess server, through email or by the postal system; less common methods which have been employed include fax and homing pigeon...

.

He was born in Bath, Somerset

Somerset

The ceremonial and non-metropolitan county of Somerset in South West England borders Bristol and Gloucestershire to the north, Wiltshire to the east, Dorset to the south-east, and Devon to the south-west. It is partly bounded to the north and west by the Bristol Channel and the estuary of the...

 studied English at New College at the University of Oxford and died in Wallingford, Oxfordshire. Eugene Wason

Eugene Wason

Eugene Wason was a Scottish lawyer and Liberal politician who sat in the House of Commons in three periods between 1885 and 1918.-Family:...

 was his grandfather.

Publications

Wason wrote the following books:

• Thinking and Reasoning (co-edited with P N Johnson-Laird
  Philip Johnson-Laird
  Philip Johnson-Laird is a professor at Princeton University's Department of Psychology and author of several notable books on human cognition and the psychology of reasoning....
  
  , 1968)
• Psychology of Reasoning: Structure and Content (with P N Johnson-Laird, 1972)
• Thinking: Readings in Cognitive Science (co-edited with P N Johnson-Laird, 1977)
• The Psychology of Chess (with William Hartston, 1983).