24. Arithmetic, central here as also in the Spanish Chapel, for the same reasons; here, more impatiently asserting, with both hands, that two, on the right, you observe-and two on the left-do indeed and for ever make Four. Keep your accounts, you, with your book of double entry, on that principle; and you will be safe in this world and the next, in your steward's office. But by no means so, if you ever admit the usurers Gospel of Arithmetic, that two and two make Five. You see by the rich hem of his robe that the asserter of this economical first principle is a man well to do in the world.
25. Logic. The art of Demonstration. Vulgarest of the whole series, far too expressive of the mode in which argument is conducted by those who are not masters of its reins.
26. Song.
The essential power of music in animal life. Orpheus. the symbol of it all, the inventor properly of Music, the Law of Kindness, as Dadalus of Music, the Law of Construction. Hence the "Orphic life" is one of ideal mercy, (vegetarian,) - Plato, Laws, Book VI., 782, - and he is named first after Dadalus, and in balance to him as head of the school of harmonists, in Book III., 677, (Steph.) Look for the two singing birds clapping their wings in the tree above him; then the five mystic beasts, - closest to his feet the irredeemable boar; then lion and bear, tiger, unicorn, and fiery dragon closest to his head, the flames of its mouth mingling with his breath as he sings. The audient eagle, alas! has lost the beak, and is only recognizable by his proud holding of himself; the duck, sleepily delighted after muddy dinner, close to his shoulder, is a true conquest. Hoopoe, or indefinite bird of crested race, behind; of the other three no clear certainty. The leafage throughout such as only Luca could do, and the whole consummate in skill and understanding.
27. Harmony.
Music of Song, in the full power of it, meaning perfect education in all art of the Muses and of civilized life: the mystery of its concord is taken for the symbol of that of a perfect state; one day, doubtless, of the perfect world. So prophesies the last corner stone of the Shepherd's Tower.