My understanding of Copernicus’s argument is that it doesn’t stand out for its superior coincidence with observed facts—Ptolemy’s calculations (and observations) may actually have been slightly more accurate—but rather that the geometry in Copernicus explains as necessary things that are merely notable coincidences in Ptolemy.
Ptolemy was aware of contemporary heliocentric theories, though. He admitted in Almagest that he had no knock-down argument against such theories, except that it’s plainly ridiculous to think that the Earth moves—after all, how would birds keep up with it while flying through the air? His astronomy is also justified by a quasi-Aristotelian metaphysics/theology, which he was probably aware was highly speculative. (There’s a minority opinion among scholars of Ptolemy that he secretly was a heliocentrist.)
I think a lot of Copernicus’s importance might be symbolic, showing that 1) empirical science can deny received truth, and 2) human life (and therefore life in general) is not the center of the universe. The second, especially, makes teleological physics much more difficult.
John,
My understanding of Copernicus’s argument is that it doesn’t stand out for its superior coincidence with observed facts—Ptolemy’s calculations (and observations) may actually have been slightly more accurate—but rather that the geometry in Copernicus explains as necessary things that are merely notable coincidences in Ptolemy.
Ptolemy was aware of contemporary heliocentric theories, though. He admitted in Almagest that he had no knock-down argument against such theories, except that it’s plainly ridiculous to think that the Earth moves—after all, how would birds keep up with it while flying through the air? His astronomy is also justified by a quasi-Aristotelian metaphysics/theology, which he was probably aware was highly speculative. (There’s a minority opinion among scholars of Ptolemy that he secretly was a heliocentrist.)
I think a lot of Copernicus’s importance might be symbolic, showing that 1) empirical science can deny received truth, and 2) human life (and therefore life in general) is not the center of the universe. The second, especially, makes teleological physics much more difficult.