For the department of Physics Seneca has much more respect, and he evidently devoted much attention to it. We have traces of some lost works of his on scientific subjects, and there is still extant a treatise in seven books on _Natural Questions_, which became a handbook of science in the Middle Ages.(1629) It deals with such subjects as we meet with in the poem of Lucretius, thunder and lightning, winds and earthquakes, and rising and failing springs. But it has perhaps less of the scientific spirit than Lucretius, according to our modern standards. We have abundant reference to old physical authorities, to Thales, Anaximenes, Anaximander, Diogenes of Apollonia, to Caecina and Attalus. But the conception of any scientific method beyond more or less ingenious hypothesis, or of any scientific verification of hypothesis, is utterly absent. This is of course a general characteristic of most of the scientific effort of antiquity. The truth is that, although Seneca probably had some interest in natural phenomena, he had a far more profound interest in human nature and human destiny. The older Stoics, with some variations, subordinated Physics to Ethics, as of inferior and only subsidiary importance.(1630) Seneca carries this subordination almost to extremes, although he also is sometimes inconsistent.(1631) He thinks it significant that while the World-Spirit has hidden gold, the great tempter and corruptor, far beneath our feet, it has displayed, in mysterious yet pompous splendour, in the azure canopy above us, the heavenly orbs which are popularly believed to control our destiny in the material sense, and which may really govern it, by raising our minds to the contemplation of an infinite mystery and a marvellous order.(1632) To Seneca, as to Kant, there seems a mystic tie between the starry heavens above and the moral law within. In the prologue to the _Natural Questions_, indeed, carried away for the moment by the grandeur of his theme, Seneca seems to exalt the contemplation of the infinite distances and mysterious depths and majestic order of the stellar world far above the moral struggles of our mundane life. The earth shrinks to a mere point in infinitude, an ant-hill where the human insects mark out their Lilliputian territories and make their wars and voyages for their lifetime of an hour.(1633) This, however, is rather a piece of rhetoric than a careful statement of Seneca’s real view. In the Letters, again and again, we are told that virtue is the one important thing, that the conquest of passion raises man to be equal to God,(1634) and that in the release of the rational or divine part of us from bondage to the flesh, man recovers a lost liberty, a primeval dignity. But in this struggle the spirit may refresh and elevate itself by looking up to the divine world from which it draws its origin, and to which it may, perchance, return. To Seneca’s mind the so-called physics really involve theology and metaphysics.