Lucretius' On the Nature of Things (http://en.wikipedia.org/wiki/On_the_Nature_of_Things) is considered one of the most beautiful epic poem ever written and the subject can be summed up as the rejection of religion in favor of the physical sciences. Written before Christianity even existed, Lucretius describes atoms, the movement of mass, the infinite nature of the universe, and the materialistic nature of the soul. Beautiful indeed.