I know, I know - similar questions have been asked before, but after reading so many answers here and elsewhere my intuitions have been scrambled and I have lost confidence in my normal practice...
Stylistics originally developed out of what was known in the past as 'rhetoric'.
Stylistics originally developed out of what was known in the past as "rhetoric".
Stylistics originally developed out of what was known in the past as rhetoric.
Normally (and throughout the previous hundred+ pages I have just proof-read) I would have favoured single quotation marks to indicate that I am mentioning rather than using a word. I'm reluctant to introduce an inconsistency into my proofing, but somehow the single quotation marks look quite wrong in these sentences - the single quotation marks seem to suggest an unusual word or a non-standard use, whereas italics seems much more natural. Is there actually a subtle difference that I can't quite coax into consciousness? Or am I just tired...?
Similarly, 'philology', linguistics' and 'stylistics' in the following sentences (bolded just to highlight the words I am talking about):
During the nineteenth century rhetoric was incorporated into linguistics, which was known at that time as philology.
The emphasis shifted to other areas of language which all fall under the umbrella of linguistics. [Neither quotation marks nor italics for 'linguistics' in this sentence?]
After that, in the 1960s, the sub-discipline known as stylistics was born.