Introduction: What is an affordance?

James Gibson wanted to understand how the perception-that is, an animal’s only means of collecting the information from outside itself-can inform the animal about the meanings of environmental objects. J. J. Gibson and Crooks also described another precursor to Gibson’s affordance concept, that is, how prospective control of the vehicle could be accomplished through the regulation of a behaviorally relevant ratio of factors. J. J. Gibson discussed the possibility of perceiving spatial meanings. Specifically, he concluded that “meanings and spatial properties are not entirely separable from one another; meaning is not wholly detachable from color, form, and texture. Some individuals have recently offered their refinements or formalizations of the Gibson’s affordance concept. These works are quite valuable, but reading them, and the discussions that they generate, gives the impression that there is still a lot of work to be done.