The categories of animals reminds me of the small world/seven degrees of separation thesis, that you'll know a lot of people who are in a tightly connected group, but you'll also know a handful of people who are distantly connected. These distant connections allow you to (theoretically) reach anyone in the world in seven steps. The people are the animals, the tightly connected groups are the categories of animals, and the distantly connected people are associations to another category.
He missed the entire class of categories that are based on the name of the animal (e.g. starting with the same letter). I think his multiple-personality technique is a neat treat for bringing different kinds of associations to the fore. That's assuming that you have the (now-meta) connection to the appropriate person in the first place. For example, he didn't think of imagining he's a lexicographer.
BTW: I wish he'd leave some white-space to separate hints that he doesn't want you to read.
He missed the entire class of categories that are based on the name of the animal (e.g. starting with the same letter). I think his multiple-personality technique is a neat treat for bringing different kinds of associations to the fore. That's assuming that you have the (now-meta) connection to the appropriate person in the first place. For example, he didn't think of imagining he's a lexicographer.
BTW: I wish he'd leave some white-space to separate hints that he doesn't want you to read.