James J. Gibson (born January 27, 1904, McConnelsville, Ohio, U.S.—died December 11, 1979, Ithaca, New York) was an American psychologist whose theories of visual perception were influential among some schools of psychology and philosophy in the late 20th century.
After receiving a Ph.D. in psychology at Princeton University in 1928, Gibson joined the faculty of Smith College. He married Eleanor J. Gibson (née Jack)—who would become a prominent psychologist in her own right—in 1932. During World War II he served in the Army Air Forces (1942–46), where he did research on visual aircraft identification and on increasing the effectiveness of training films, among other topics. After the war he returned to Smith College before moving to Cornell University in 1949. He retired in 1972.
Gibson developed what he called an “ecological approach” to the study of visual perception, according to which humans perceive their environments directly, without mediation by cognitive processes or by mental entities such as sense-data. Perceiving a tree, for example, does not consist of constructing a mental image of a tree from stimuli (light energy) entering the visual system and then attributing the visual properties of the image to the tree itself. Instead, one directly sees the visual properties of the tree. This idea was radical because it contradicted a centuries-old model of the origins of human knowledge. As Gibson himself put it, “The old idea that sensory inputs are converted into perceptions by operations of the mind is rejected.”
Gibson created a highly influential theory of “affordances,” which are qualities of an object or environment that communicate opportunities to do certain things (e.g., dark shade indicates an opportunity to get out of the sunshine; a thick cushion signals the availability of comfortable seating). According to Gibson, affordances exist naturally and are directly perceived by the viewer. His work had a large impact in human-factors engineering, or ergonomics, which is partly concerned with the perceived affordances in products designed for human use.
In addition to The Ecological Approach to Visual Perception (1979), Gibson’s most important writings include The Perception of the Visual World (1950) and The Senses Considered as Perceptual Systems (1966). His followers organized the International Society for Ecological Psychology in 1981.