In the comments of the last post, I was challenged to think a bit more carefully about categories, and more generally about my thinking style. This is not a response to those comments, but something motivated by me thinking about the topic.
I’m a messy thinker. I like to see masses of data, lots of overloaded axes, partial information, overlapping categories and contradiction. I like to see patterns arise out of the mess, and am less comfortable with reorganizing the mess into some form of order (though that is sometimes necessary).
Borges writes on categories (in El idioma analítico de John Wilkins, 1942)
“These ambiguities, redundancies, and deficiencies recall those attributed by Dr. Franz Kuhn to a certain Chinese encyclopaedia called the Heavenly Emporium of Benevolent Knowledge. In its distant pages it is written that animals are divided into (a) those that belong to the emperor; (b) embalmed ones; (c) those that are trained; (d) suckling pigs; (e) mermaids; (f) fabulous ones; (g) stray dogs; (h) those that are included in this classification; (i) those that tremble as if they were mad; (j) innumerable ones; (k) those drawn with a very fine camel’s-hair brush; (l) etcetera; (m) those that have just broken the flower vase; (n) those that at a distance resemble flies.”
This passage has been picked up by other writers, notably Foucault. Some who took Borges seriously on his identification of a source (a bad move, Borges is often fictive about scholarship) made rather racist points about Chinese conceptual systems. Others simply laughed at how terrible such a classification would be.
I think it sounds cool.
I think part of the gaffawing is because a lot of writers on this passage miss the implication of (h). It is not the case that each animal can appear in only one category. So this is a categorization based on a set of features that (though intended as humorous) are presumably all useful in some way.
Here are two categorizations:
I divide animals into these categories: vertebrates and invertebrates. Of the vertebrates I sub-divide them into mammals, birds, fish, reptiles and amphibians. The mammals I further divide into monotremes, marsupials and placental mammals.
I divide animals into these categories: those I own, those that are dangerous, those I have in a book, those that can be eaten, those my nieces would like on a lunchbox, and those that I’d like to paint.
Which is better? The latter, it seems to me. Give me Borges’s encyclopaedia any day.
How about you?
PS: There are serious implications behind this. I do make these kinds of decisions regularly in my day job. I’ve been trained to think that hierarchies of categories are better, but I’ve time and time found that for real data and real human needs, ad-hoc mixed categories (or ‘tags’, which are a version of the same thing) are superior.
 Apologies for the biological naivety to anyone who would have expected better things given my background. But the naivety makes a related point: the first style of classification seems systematic, but is actually just as arbitrary.