How does one define the term “network”?

I ask this question because I have started to work through a review copy of Niall Ferguson’s The Square and the Tower. So far, it is an attempt to reinterpret history as a contest between networks and hierarchies. So naturally, I want to see the two terms defined. And they are not. It is amazing how often that happens. Somebody writes a book about culture and does not bother to carefully define culture. Am I the only one who finds that deeply annoying?

Ferguson defines a hierarchy as a network with particular characteristics. A hierarchy is heavy on top-down connections and light on horizontal or bottom-up connections. I am being terse. He is more explicit. But since he never defines the term network, calling a hierarchy a particular type of network still leaves hierarchy undefined.

When I type “network” into Google, it gives me the movie with the famous line “I’m mad as hell and I’m not going to take it any more.” Maybe Google knows how peeved I am when a book never defines the terms that are its main focus.

One challenge is that we use the term network very promiscuously. We speak of road networks, computer networks, social networks, and so on. Maybe a definition is elusive because the term means different things in these different contexts.

Anyway, let me try to give a definition of a network, and see how you like it:

A network is a set of channels (or conduits) through which resources can flow according to particular protocols between nodes (or endpoints).

With a network of roads, the resources that flow are vehicles and their contents. The protocols usually allow for bidirectional flow.

With the Internet, the resources that flow are digital messages. The protocols include the Internet Protocols.

With real-life social networks, the “resources” are knowledge about someone based on personal acquaintanceship. The “protocols” are customs about how much we know about friends, family, and co-workers in our immediate circle. Yes, I’m stretching here.

When we talk about a political or economic contest between a network and a hierarchy, what are the resources that flow? Maybe the resources are “instructions” and “information.” They flow vertically in a hierarchy, and more horizontally in a non-hierarchy.

I have one more quibble about Ferguson. That is, the metaphor of a tower (managed centrally) and a square (emergent) strikes me as similar to the metaphor of the Cathedral and the Bazaar, found in a famous essay by Eric Raymond. I looked in the index, and there is a citation of Raymond’s essay, but Ferguson never remarks on the similarity of the metaphor!

By the way, I am probably going to like Ferguson’s book very much by the time I finish it.