Mike uses the analogy stream (e.g. Facebook/Instagram/Twitter... feed or blog) and garden (e.g. wiki). He argues that people are too busy exploiting the stream model, which is made for conversation, that they actually don't create something new. He also argues that having a (federated) wiki to record your thoughts supports much deeper thinking and learning at the same time.

Mike writes

Everybody wants to play in the Stream, but no one wants to build the Garden.

and later

... how much time we’ve all spent arguing, promoting our ideas, and how little time we’ve spent contributing to the general pool of knowledge.

Why? Because we’re infatuated with the stream, infatuated with our own voice, with the argument we’re in, the point we’re trying to make, the people in our circle we’re talking to.

People say, well yes, but Wikipedia! Look at Wikipedia!

Yes, let’s talk about Wikipedia. There’s a billion people posting what they think about crap on Facebook.

There’s about 31,000 active wikipedians that hold English Wikipedia together. That’s about the population of Stanford University, students, faculty and staff combined, for the entire English speaking world.