You recently wrote, "We believed the earth was flat. Augustine considered that
from his understanding of the Bible." I am not sure what you meant by
"considered", but if you meant that he believed the earth was flat, do you
have a reference?
In Book XVI, Chapter 9 of The City of God Augustine addresses the question of
whether Antipodae exist, i. e. "men living on the far side of the earth,
where the sun rises when it sets for us". He thought that even if there was
land in the other hemisphere that rose higher than the surface of the ocean,
it was too far away for men to sail to it, and so he concluded that there
were no men there. I have always assumed that his discussion presupposed a
round earth.
Gordon Brown
Department of Mathematics
University of Colorado
Boulder, CO 80309-0395