Psychologist James J. Gibson originally introduced the term in his 1977 article "The Theory of Affordances"[1] and explored it more fully in his book The Ecological Approach to Visual Perception[2] in 1979. He defined affordances as all "action possibilities" latent in the environment, independent of an individual's ability to recognize them, but always in relation to agents (people or animals) and therefore dependent on their capabilities. For instance, a set of steps which rises four feet high does not afford the act of climbing if the actor is a crawling infant.