I'd like to clarify; I am talking about fiction writers. I do not mean to include any member of the intellectual community that hypothesized on another continent's existence. Was there a Jules Verne of ancient Rome? Or could there have been elaborate tales of another continent across the sea, filled with monsters and strange beings, told to young Japanese children?

I thought of this question while reading Thucydides' Peloponnesian War. To the Greeks, with a few exceptions, their continent was the world. I asked myself if they may have ever considered that they barely knew of half the world. Of course, I don't know the answer, so I pass it off to you guys!