J.J. Gibson and Marshall McLuhan: A survey of terminology and a proposed extension of the theory of affordances

摘要

Psychologist James J. Gibson coined the word “affordance”in 1979, to describe the relationship between the abilities ofa living creature, and features in the environment that affordaction for those abilities. An affordance, therefore, isphysically real, but is defined as an affordance only inreference to a particular creature. This term has been widelyadopted, and is now found in design, education, andcognitive science. Sometimes it is used in Gibson’s originalmeaning, but it has also been applied to broader discussionsof social and cognitive activities, resulting in a certainconfusion of terminology. A short summary reveals thevariety of current uses for the term, and goes further topropose that this range may be simplified by applyingMarshall McLuhan’s observation that “media are theextensions of mankind.” In that analysis, an object like acup is an extension of cupped hands, because, like hands, itholds water. Defining some objects as body-extensionsmakes it clear that affordances can be modified in twoways: by changing either features that are available in theenvironment, or the extended abilities of the user. Thisdistinction simplifies the description of different types ofaffordances, and may help designers in planning effectiveexperiences for users.