Affordances

Affordances is the plural form of affordance, the relational property of an environment relative to an organism that describes what the environment offers for action. The plural form is significant because organisms do not encounter isolated affordances in the wild; they navigate fields of affordances — dense webs of competing and complementary action possibilities that structure every moment of perception.

The concept of a field of affordances was developed by ecological psychologists to capture the fact that perception is not a sequence of discrete detections but a continuous attunement to a structured landscape of possibilities. A climber on a rock face does not perceive individual affordances one by one; they perceive a gestalt in which some affordances stand out as invitations and others recede into the background. The field is dynamically organized by the organism's current needs, skills, and concerns — what is sometimes called the organism's sensorimotor situation.

This pluralistic framing has implications for design theory and urban planning. A well-designed environment is not one that provides a single correct affordance for each task; it is one that provides a rich field of affordances that supports multiple modes of engagement and can be restructured as the user's needs change. The universal design movement, which seeks to create environments usable by people with diverse abilities, is essentially an attempt to expand the field of affordances available to all users.