Most adults have some childlike fascination for making and arranging larger structures out of smaller ones. - Marvin Minsky

When David Marr at MIT moved into computer vision, he generated a lot of excitement, but he hit up against the problem of knowledge representation; he had no good representations for knowledge in his vision systems.

It would seem that making unusual connections is unusually difficult and, often, rather "indirect"—be it via words, images, or whatever. The bizarre structures used by mnemonist (and, presumably unknowingly, by each of us) suggests that arbitrary connections require devious pathways.

Only the surface of reason is rational. I don't mean that understanding emotion is easy, only that understanding reason is probably harder.