Matter-of-Fact, Spiced with Wit to Taste
Asimov is not a guy for messing about. No time for fluff. No need to wax poetical. Just tell us the story. Want to see what we're talking about? Here's what we're talking about:
Wienis was groping visibly for self-control. "Give me none of that, Hardin. Save it for the mob."
"My dear Wienis, whoever do you think I am saving it for? I imagine that for the last half hour every temple on Anacreon has been the center of a mob listening to a priest." (III.6.62-63)
This is super direct, telling you exactly what's going on (e.g., Wienis has some self-control issues). Even the dialogue is to the point. Hardin doesn't dance around telling Wienis that he out-maneuvered him in their political game. He just spells it out.
Here's the thing. Matter-of-fact can be kind of…boring. Ever read a tech manual on the proper installation of toner ink? Snore-fest. Asimov knows this, and so inserts his trademark wit where he needs to spice things up—usually in the dialogue.
In the example above, you'll notice that Hardin enjoys toying with Wienis, calling him "my dear Wienis." He even suggests he's going along with Wienis's plan by controlling the mob, just to get under the guy's skin that extra bit. This witty sprinkling really helps get the tofu-bland exposition up on its feet.