59. The only consistent and incontrovertable view to take is that all these phenomena are either works of God or of evil spirits. I have no doubt that the dancing goats (stars), the flying serpents, fiery lances, and the like, are produced by evil spirits, which thus gambol in the air, either to terrify or to deceive men. The flames which appear on board of ships were thought by the heathen to be Castor and Pollux. Sometimes the image of a moon appears above the ears of horses. It is certain that all these things are due to the antics of evil spirits in the air, though Aristotle believes them to be luminous air, just as he also declares that a comet is shining vapor. 60. To me it appears that we shall move with greater security and certainty, when, arguing from cause to effect, we conclude that the comet blazes, when it pleases God, as a sign of calamity, just as the rainbow glows, when it pleases God as a sign of mercy. Who can compute all the causes which produce the appearance of the rainbow in such diversity of beautiful color, and in the form of an arch of perfect curvature? The arrangement of the clouds alone surely does not produce this perfection. Hence it is by the will and the promise of God, and fulfilling his pleasure, that the rainbow is a sign to man and beast that there will nevermore at any time be a flood. 61. In recognition of this token we ought to give thanks to God. As often as the rainbow appears, it proclaims to the world with a loud voice, as it were, the story of the wrath of God, which once destroyed the world by a flood. And it proclaims solace for us, so that we may conclude that God is propitious to us henceforth and will never again visit upon us so fearful a punishment. It teaches both the love and the fear of God, the highest virtues, of which philosophy knows nothing. Philosophy only disputes about material and formal causes. It does not know the final cause of this most beautiful creation. But theology does explain it. 62. In this connection also the question has received much attention whether the rainbow existed from the beginning. And in this controversy much force has been displayed. Since it is written above (ch 2, 23) that God created heaven and earth in six days, and then rested from all his works, some conclude that the rainbow existed from the beginning. Otherwise it would follow that creation extended beyond those six days. What, however, occurred in Noah's time is this, that the rainbow, created in the beginning, was selected by God and made, through a new word, a fixed symbol, having existed hitherto without special significance. To support this view, they even quote the word of Solomon that "there is no new thing under the sun," Ec 1, 9. On this they base their argument that after those six days no new thing has been created.