But how is it that the original miracles of the creation of Adam and Eve seem to us so wonderful and so incredible; while the still standing miracle of the continuous propagation of man, which we all know and daily see, excites no wonder or admiration at all? It is because, as Augustine says, "Miracles become no miracles at all, by familiarity." Hence we wonder not at the admirable light of the sun, because we see it every day. For the same reason we admire not other gifts and blessings of God's creation, but are blind and deaf to them all. On the same ground Pythagoras well said, that a most sweet and marvelous concert of sounds was effected by the harmony and velocity of the motions and revolutions of the heavenly bodies, but that men became deaf to this celestial concert by hearing it continually; just as those who are accustomed to the roarings of the Nile are not at all affected by the thunders of the water, while to others, who are not accustomed to them, they are awful and intolerable. There is no doubt that Pythagoras received this idea from the fathers by tradition. Not however that they really believed in any actual harmony of sounds, made by the motions of the heavenly bodies. Their meaning was that the creation of these celestial bodies was truly delightful and marvelous; but that their beauty and their glory were not duly observed by us ungrateful and insensate beings; and that we did not render unto God the praises due to him, as the Creator of such wonderful and admirable creatures. Thus also it is a great miracle that a small seed placed in the ground should cause to spring forth a lofty and magnificent oak. But as this is so familiar as an everyday occurrence, it makes no impression upon us; just so little do we appreciate the nature and manner of our own propagation. For why is it not worthy of the highest admiration that a woman should receive human seed, which then grows, and as Job 10:11 so beautifully says, "Thou hast clothed me with skin and flesh, and knit me together with bones and sinews;" that is, formed me and nourished me in my mother until I was matured to live in the air, separated from her. In this new state of existence I received no new nourishment, but it came from the same mother in a new way and manner, in that from both breasts of my mother as from fountains, her milk went forth by which her infant was nourished. All this is most wonderful and utterly incomprehensible, but lightly esteemed by us because we have truly become deaf to this most pleasant and lovely music of nature.