CONCEPT
Scaffolding vs. Prosthesis
The distinction at the center of Bruner's framework — between temporary support that builds independent capability through graduated withdrawal, and permanent support that replaces the capability it substitutes for. The diagnostic that separates AI-as-teacher from AI-as-crutch.
Scaffolding and prosthesis are not distinguished by the quality of support. Both can be exquisitely designed, precisely calibrated, genuinely helpful. The distinction is directional: scaffolding moves toward independence, prosthesis maintains dependence. Scaffolding succeeds by becoming unnecessary. Prosthesis succeeds by remaining indispensable. The scaffold withdraws as the learner develops the capability it was providing; the prosthesis permanently replaces a function the user cannot perform independently. The distinction sounds simple and is devastating in application. The Bruner volume argues that AI support, as currently designed and economically incentivized, follows the trajectory of prosthesis rather than scaffolding — producing capability that is real but situated in the partnership between human and machine rather than in the human alone.
In The You On AI Field Guide
The distinction rests on the principle that scaffolding exists to be withdrawn. Every function the scaffold performs is temporary. The scaffold succeeds when the child builds the next pyramid alone, when the student