The document discusses various metaphors that have been used to describe learning theories and their relationship to instructional design. It describes metaphors used in behavioral learning such as "black box" and "response strengthening". It also covers metaphors for cognitive learning like "information processing" and "knowledge acquisition". Constructivist metaphors discussed include "knowledge construction", "anchoring", and "inquiry". Social constructivist metaphors include "knowledge building", "negotiations", and "participation in communities of practice".