I hypothesize that evocation of one concept triggers additional concepts learned to be similar to that one by association. Think of one thing and related things are involuntarily pulled in as well; you import a whole cluster of memories rather than a single one. (Incidentally, this is how disks pull in data – by block – except that there is usually little conceptual locality to the way the data is arranged on disk… maybe there should be, as this would be far more optimal for caching and other purposes?)

Furthermore, I hypothesize that this influences the use of additional associated concepts even outside of their intended use; i.e., it is a more general form of priming. For example, the first sentence of the Wikipedia article on retributive justice makes use of the term “eye” outside of the obvious association “eye for an eye” (which appears further below):

“Retributive justice is a theory of justice that considers that proportionate punishment is a morally acceptable response to crime, with an eye to the satisfaction and psychological benefits it can bestow to the aggrieved party, its intimates and society.”

I postulate that this is not at all incidental, but due to the pulling in of “clusters” of related ideas in memory.

There is a further use for this theory in pedagogy: by moving on from a single topic but integrating certain “key ideas” or even “key words” from a previous topic, you can reinforce that topic while introducing new material. For example, if I used the term “phylogeny” extensively while teaching students about tree data structures, then moved on and discussed genetic algorithms, I could cause students to recall the tree lecture by using the term “phylogeny” in a different context. It has essentially become a trigger point for recalling an unrelated memory.