Every now and then I come across an intriguing article that is also seminal to my interests and doctorate. Sociologica , which is the Italian Journal of Sociology, has just republished Harrison White's "Notes on the Constituents of Social Structure ". Harrison White is the Giddings Professor of Sociology at Columbia University, however his doctorate is in theoretical physics. White is very influential in network analysis and is sometimes credited with developing block-models - but I digress.

In this article White introduces the notion of a "catnet", where he brings together the ideas of categories and networks - hence catnet. The idea at the time was quite novel, yet now it seems obvious - people who are alike in some way will form networks (birds of a feather flock together). White's contribution was how to represent the various categories that might be found in a network. Further by bringing together network analysis and categories like race, gender, or education, he was able to show that categories are an artificial construct that aid understanding but of themselves are not sufficient.

I find White's original idea about categories very powerful. Take this quote for instance:

"A single category" is therefore a meaningless idea: at a minimum there is at least the residual category or box into which fall "all others," those not alike in the given respect. To say category is to mean a system of categories.

Again this seems obvious but how often do we use categories as absolutes? We all at once belong to many categories - I am simultaneously a male, husband, father, son, musician, bagpiper, businessman, and so on. The network shape will vary depending on how I attribute the network and pose the questions, but the resulting network at least has the power to reveal hitherto unknown relationships. If we are not careful the weakness of network analysis can be the myopic lens of category attribution. Understanding how we categorise things matters!

Regards, Graham