It is, of course, that the stability of the Universe rests upon ordered motion--that the 'firmament' above, around, beneath, stands firm, continues firm, on a balance of active and tremendous forces somehow harmoniously composed. Theology asks 'by What?' or 'by Whom?' Philosophy inclines rather to ask 'How?' Natural Science, allowing that for the present these questions are probably unanswerable, contents itself with mapping and measuring what it can of the various forces. But all agree about the harmony; and when a Galileo or a Newton discovers a single rule of it for us, he but makes our assurance surer. For uncounted centuries before ever hearing of Gravitation men knew of the sun that he rose and set, of the moon that she waxed and waned, of the tides that they flowed and ebbed, all regularly, at times to be predicted; of the stars that they swung as by clockwork around the pole. Says the son of Sirach: At the word of the Holy One they will stand in due order, And they will not faint in their watches. So evident is this calculated harmony that men, seeking to interpret it by what was most harmonious in themselves or in their human experience, supposed an actual Music of the Spheres inaudible to mortals: Plato as we see (who learned of Pythagoras) inventing his Octave of Sirens, perched on the whorls of the great spindle and intoning as they spin. Dante (Chaucer copying him in "The Parlement of Fowls") makes the spheres nine: and so does Milton: then listen I To the celestial _Sirens_ harmony, That sit upon the nine infolded Sphears, And sing to those that hold the vital shears, And turn the Adamantine spindle round On which the fate of gods and men is wound. Such sweet compulsion doth in musick lie To lull the daughters of _Necessity_, And keep unsteady Nature to her law, And the low world in measur'd motion draw After the heavenly tune.... If the sceptical mind object to the word _law_ as begging the question and postulating a governing intelligence with a governing will--if it tell me that when revolted Lucifer uprose in starlight-- and at the stars, Which are the brain of heaven, he look'd, and sank. Around the ancient track march'd, rank on rank, The army of unalterable law-- he was merely witnessing a series of predictable or invariable recurrences, I answer that he may be right, it suffices for my argument that they _are_ recurrent, are invariable, can be predicted. Anyhow the Universe is not Chaos (if it were, by the way, we should be unable to reason about it at all). It stands and is renewed upon a harmony: and what Plato called 'Necessity' is the Duty--compulsory or free as you or I can conceive it--the Duty of all created things to obey that harmony, the Duty of which Wordsworth tells in his noble Ode. Thou dost preserve the stars from wrong: And the most ancient heavens, through Thee, are fresh and strong. III