 This kind of speculation also belongs to the basic principles of Kepler’s philosophical optics. In Chapter 1 of APO (“On the Nature of Light”), Kepler gives a new account of this “Trinitarian Cosmogony.” As he admits in a letter to Thomas Harriot (1560–1621), his approach here is more theological than optical (KGW 15, let. 394, p. 348, lin. 18). Similar to his speculations in MC, Kepler explains again the symmetry between God and the Creation, but now he goes slightly beyond the limits of a theologico-geometrical reflection. Firstly, he seems to assume that the bodies of the world were provided in the Creation with some powers which enable them to exceed their geometrical limits and to act on other bodies (magnetic power is a good example of this). Secondly, the principle of symmetry introduced into matter constitutes “the most excellent thing in the whole corporeal world, the matrix of the animate faculties, and the chain linking the corporeal and spiritual world” (APO, Engl. trans., p. 19). Thirdly, as expressed by Kepler in a wonderful, long Latin sentence, with multiple subordinations, this principle “has passed over into the same laws (in leges easdem) by which the world was to be furnished” (ibid., p. 20; the original passage is in KGW 2, p. 19: the marginal note in the edition is “lucis encomium”). Finally, these reflections are concluded with a remark, in which—as with Copernicus, Marsilio Ficino, and others—the central position of the Sun is legitimated because of its function in spreading light and, indirectly, life. Similar speculations are still present in EAC (KGW 7, pp. 47–48 and 267). It is also worth noting that these speculations are of vital importance to the special way in which Kepler conceived of astrology (see, for instance, De fundamentis astrologiae certioribus with Engl. trans. and commentary in Field 1984).