  This paper argues that Tycho Brahe's "principal argument against Copernicus"
(as the astronomer Christiaan Huygens called it) likely derived from a much
older argument regarding the sizes of the "two great lights" described in the
first chapter of the book of Genesis. Brahe's argument, that in the Copernican
system stars would have to be absurdly large, played an important role in
opposition to the Copernican system in the seventeenth century. Brahe presented
the argument in an exchange of letters with Christoph Rothmann in 1588-89.
Within that exchange Rothmann and Brahe touched both on the question of the two
great lights of Genesis and on theologians such as Augustine of Hippo who
treated that question. The fundamentals of Brahe's important line of argument
against Copernicus thus well pre-dated Copernicus and Brahe.
