Sensitivity to hierarchical relations among affordances in the assembly of asymmetric tools.

Research on affordances typically has focused on the identification and perception of a single affordance. However, in daily life, multiple affordances are available. We investigated potential hierarchical relations among affordances of tools in two experiments. In Experiment 1, participants assembled a tool consisting of an L-shaped object and attached masses so as to perform a particular behavior on a target object-tipping over or sliding it-located at a particular distance from the participant. In Experiment 2, participants performed the same task with additional precision constraints on the tool use task. In both experiments, participants selected longer objects when target objects were farther away and added more mass to tools to be used for tipping than for sliding. The results were compatible with the hypothesis that participants were simultaneously sensitive to affordances for tool assembly (as revealed in their actualization of affordances in tool assembly) and, prospectively, to affordances for tool use (as revealed in relations between assembled tools and the nature of tasks for which they were assembled).