1. the learning principle that connections between items are more readily formed if the items are related in terms of sense (i.e., they “belong together”) rather than proximity or contiguity. For example, in “Mary is 12, Sasha is 13, and Alfre is 14,” the 12–Sasha proximity bond is weaker than the 12–Mary belongingness bond. [proposed by Edward L. Thorndike]
2. the idea that associations between some stimuli and responses are readily acquired because of evolutionary predispositions. See preparedness.