And, moreover, it is the highest of all; for, as Aristotle says at the beginning of his treatise on the Soul, Science is of high nobility, from the nobleness of its subject, and from its certainty; and this more than any of the above-mentioned is noble and high, from its noble and high subject, which is the movement of the heavens; and high and noble from its certainty, which is without any defect, as one that proceeds from a most perfect and regular source. And if any one thinks there is any defect in it, the defect is not on the side of the Science, but, as Ptolemy says, it comes from our negligence, and to that it should be attributed.”