Richard Langton Gregory. 24 July 1923—17 May 2010

Richard Gregory was a pioneer of cognitive psychology. Much of his scientific work involved the development and interpretation of visual illusions, which he used as a tool to work out the perceptual mechanisms involved in the way that the visual world is normally perceived. He was also an inventor, developing a technique for viewing microscopic objects in three dimensions, and a method for taking sharp telescope images through an unstable atmosphere. He was a man of great charm, enthusiasm and wit, who listed his hobbies as punning and pondering. He was to become an outstanding public communicator of scientific ideas. He gave the Royal Institution Christmas Lectures (‘The intelligent eye’) in 1967, was a founder member of the Experimental Psychology Society, set up his own journal,Perception , in 1972, and in 1978 founded the Exploratory, a hands-on science centre in Bristol. His work on illusions and his interest in painting led to a collaboration with the art historian Sir Ernst Gombrich, resulting in the bookIllusion in nature and art (1973) and an exhibition at the Institute of Contemporary Art. Other books includedMind in science (1981) andThe Oxford companion to the mind (1987), for which he was both editor and a major contributor. The book for which he is best known is the wonderfully accessibleEye and brain , whose five editions (1966–1997) and many translations have inspired students of all ages.