> Plato must have been cognizant of the great size of our globe, and of other continents, because he said in Phaedo that the Mediterranean people occupied 'only a small portion of the earth.'

> That's inspiring. So, before the Vikings, the New World wasn't an impossibility. It was in fact as old as any other point on Earth.

Very well said. If nothing else this also shows the deep origins of the development of the scientific method: propose a theory based on (in this case) extrapolation, then prove it later on with evidence. In many ways, human civilization, and especially human knowledge can be thought of as a manifestation of this simple formula.

The existence of a kind of extrapolation-based forethought prior to the actual process of exploration undertaken by humankind evidenced here would fall neatly into this progression.