In prose, without quotation marks. I found it jarring the first time I got corrected for casually using quotation marks on HN (many years ago --- I think by Paul Graham!) and felt for sometime afterwards that it was evidence about how needlessly prickly the site is. But I'm now glad to have left the habit of using question marks rhetorically behind in pretty much all of my writing.
You can still use quotes if you really want to; you just have to write clearly that you aren't making a literal quotation --- to be clear that you're not putting words in someone else's mouth. But I find that it's rarely worth the effort to do so.
You can still use quotes if you really want to; you just have to write clearly that you aren't making a literal quotation --- to be clear that you're not putting words in someone else's mouth. But I find that it's rarely worth the effort to do so.