February 15th was the birthday of Galileo Galilei (1564). It is
worth revisiting, after nearly four and a half centuries, the
arguments used by Galileo to defend his theory of a heliocentric
solar system based on his celestial observations as presented in
his Letter to the Grand Duchess Christina (Concerning the Use of
Biblical Quotations in Matters of Science, 1615). Galileo begins
his letter: Some years ago...I discovered in the heavens many
things that had not been seen before our own age. The novelty of
these things...stirred up against me no small number of
professors--as if I had placed these things in the sky with my
own hands in order to upset nature and overturn the sciences.
They seemed to forget that the increase of known truths
stimulates the investigation, establishment and growth of the
arts; not their diminution or destruction. Showing greater
fondness for their own opinions than for truth, they sought to
deny and disprove the new things which, if they had cared to
look for themselves, their ow