I have been reading Aristotle by John Herman Randall, Jr. (1960 Columbia Press). Chapter VII, “The Heavens” discusses Aristotle’s cosmology. It really hit home for me why the Catholic church took so much offense from Galileo and other 16th/17th Century natural philosophers saying that the Earth was not the center of the universe, that the Earth revolved around the sun along with the planets, etc.
The church had adopted Aristotle’s ideas by that time, and that included the notion that as you traveled out away from the Earth, you would approach divine perfection. Unlike Plato who thought that such divine perfection existed in some other realm, Aristotle said such perfection was the outermost layer of the Universe. As evidence of this perfection, it was pointed out that the stars moved in an apparently unchanging circular pattern through the night sky, and such circular motion was considered “divine” or “perfect”. The stars, unlike the planets, exhibited this circular motion because they were closer to perfection.
As the Church became increasingly Aristotelian, it would have adopted the notion that this outer realm of the universe was where the divine resided, rather than in some “other realm” outside the universe as a more Platonic Christianity would hold. However, the natural philosophers of the 16th/17th century began to show that the rest of the universe operated in accordance with the same natural laws as the ones operative here on Earth, and that the Earth revolved around the sun. This would have started calling into question the whole scheme in which the Earth is at the center, and “imperfect”, while as you moved out away from the Earth, you approached “perfection”, and a different set of natural laws from the ones on Earth. But, if the Church had already rejected the Platonic notion of the divine in another realm, and the divine also didn’t exist in this universe, then that would tend to suggest that it didn’t exist anywhere. It wasn’t just a question of Astronomy for the Church, it literally called into question it’s most fundamental tenants.
