Once when teaching a class (a three-hour one), I threw everyone in the class for a loop by spending almost the first hour arguing in favor of David Hume's argument in the essay on miracles; the next hour, after the break, arguing against; and, after a second break, most of the third hour arguing in favor of it. At the end I took a poll of the class, asking whether they thought it worked. Then I put my own vote up; of course, I don't think it does. Some of the students thought I was deliberately being perverse. But, as I pointed out to them, some arguments are best understood sic et non.
(I didn't use that phrase, of course.)
