Page:Popular Science Monthly Volume 10.djvu/562

544 with great earnestness and assiduity, held many views concerning the earth that were very reasonable for his time. Yet, in the absence of facts, nothing was left for him but to rely upon logic. He had certain ideas of what is natural and what is perfect, and from



these he reasoned as to what must be and therefore what is. To the question whether the earth turns or the heavens turn, he replies that the earth is evidently in repose, not only because we see it to be so, but because it is a necessity that it should be, that is, because repose is natural to the earth. If it be asked why the stars must move around



the earth, he replies, it is natural that they should, because a circle is the most perfect line, because it has no ends, and it must therefore be described by the perfect stars. That the earth is the centre of the universe, and is at rest, is furthermore proved by Aristotle from