Western Civilization_ Volume B_ 1300 to 1815 - Jackson J. Spielvogel [223]
Robert Bellarmine, Letter to Paolo Foscarini, 1615
First. I say that it seems to me that Your Reverence and Galileo did prudently to content yourself with speaking hypothetically, and not absolutely, as I have always believed that Copernicus spoke. For to say that, assuming the earth moves and the sun stands still, all the appearances are saved better than with eccentrics and epi-cycles, is to speak well; there is no danger in this, and it is sufficient for mathematicians. But to want to affirm that the sun really is fixed in the center of the heavens and only revolves around itself (i.e., turns upon its axis) without traveling from east to west, and that the earth is situated in the third sphere and revolves with great speed around the sun, is a very dangerous thing, not only by irritating all the philosophers and scholastic theologians, but also by injuring our holy faith and rendering the Holy Scriptures false. For Your Reverence has demonstrated many ways of explaining Holy Scripture, but you have not applied them in particular, and without a doubt you would have found it most difficult if you had attempted to explain all the passages which you yourself have cited.
Second. I say that, as you know, the Council [of Trent] prohibits expounding the Scriptures contrary to the common agreement of the holy Fathers. And if Your Reverence would read not only the Fathers but also the commentaries of modern writers on Genesis, Psalms, Ecclesiastes and Josue, you would find that all agree in explaining literally (ad litteram) that the sun is in the heavens and moves swiftly around the earth, and that the earth is far from the heavens and stands immobile in the center of the universe. Now consider whether in all prudence the Church could encourage giving to Scripture a sense contrary to the holy Fathers and all the Latin and Greek commentators. Nor may it be answered that this is not a matter of faith, for if it is not a matter of faith from the point of view of the subject matter, it is on the part of the ones who have spoken… .
Third. I say that if there were a true demonstration that the sun was in the center of the universe and the earth in the third sphere, and that the sun did not travel around the earth but the earth circled the sun, then it would be necessary to proceed with great caution in explaining the passages of Scripture which seemed contrary, and we would rather have to say that we did not understand them than to say that something was false which has been demonstrated. But I do not believe that there is any such demonstration; none has been shown to me. It is not the same thing to show that the appearances are saved by assuming that the sun really is in the center and the earth in the heavens. I believe that the first demonstration might exist, but I have grave doubts about the second, and in a case of doubt, one may not depart from the Scriptures as explained by the holy Fathers.
What does Galileo think is the difference between knowledge about the natural world and knowledge about the spiritual world? What does Galileo suggest that his opponents should do before dismissing his ideas? In what ways does Cardinal Bellarmine attempt to refute Galileo’s ideas? Why did Galileo’s ideas represent a threat to the Catholic Church?
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Galileo made two contributions to the problem of motion. First, he demonstrated by experiments that if a uniform force was applied to an object, it would move at an accelerated speed rather than a constant speed. Moreover, Galileo discovered the principle of inertia when he argued that a body in motion continues in motion forever unless deflected by an external force. Thus, a state of uniform motion is just as natural as a state of rest. Before Galileo, natural philosophers had tried to explain motion; now their task was to explain changes in motion.
The condemnation of Galileo by the Inquisition, coming at a time