Whence Tycho's Case against Copernicus? On Genesis, Augustine, and the Stars

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.