"A few" means at least 3. You would never say "a few" when you meant "two". So the quote refers to the 17th century at the latest.
I routinely use "a couple" and "a few" to indicate vague quantities. A few is bigger than a couple, but they overlap. I know that not everyone does this (my S.O., in particular, thinks I'm wrong) but I also know that I'm not nearly alone in this habit.
Yes, certainly, there are circumstances in which "a couple" means exactly two. If I'm talking about some friends, and refer to them as "a couple" rather than "a couple of people", you'd be justified to think I meant exactly two people with some relationsh...
A monthly thread for posting rationality-related quotes you've seen recently (or had stored in your quotesfile for ages).