A subtle change of subject, or a pause longer than just a breath or two. A concise argument that has many angles to it. Lots of ways, really. Written paragraphs aren’t there to make things easy to read; they represent a focus on a particular angle of a topic.
I was listening to a bunch of fat, bearded guys talking about Harleys today at lunch.
I listened closely, and they were definately using paragraphs.
Did you tell them that?
-FrL-
No. I was discrete in my observations. They already scowl at me for laughing at them.
I was conversing with my gf last night over dinner. Breaks between paragraphs were indicated by the chewing of food. 