Conformably, also, to this doctrine of Plato concerning the sun, the emperor Julian sublimely theologizes about this divinity in his very elegant oration to him, from which the following is an extract. The apparent and splendid orbicular sun is the cause of well-being to sensible natures. And whatever we have asserted as flowing from the mighty intellectual sun among the intellectual Gods,[108] the same perfections the apparent sun communicates to apparent forms; the truth of which will be clearly evinced by contemplating invisible natures from the objects of sensible inspection. And in the first place, is not light the incorporeal and divine form of that which is diaphanous in energy? But whatever that which is diaphanous may be, which is subjected to all the elements, and is their proximate form, it is certain that it is neither corporeal nor mixed, nor does it display any of the peculiar qualities of body. Hence, you cannot affirm that heat is one of its properties, nor its contrary cold; you can neither ascribe to it hardness nor softness, nor any other tangible difference; nor attribute taste or smell as peculiarities of its essence. For a nature of this kind, which is called forth into energy by the interposition of light, is alone subject to the power of sight. But light is the form of a diaphanous essence which resembles that common matter the subject of bodies, through which it is every where diffused; and rays are the summit, and as it were flower of light, which is an incorporeal nature. According to the opinion of the Phœnicians, however, who are skilled in divine science and wisdom, the universally-diffused splendour of light is the unmingled energy of an intellect perfectly pure. And this doctrine will be found agreeable to reason, when we consider that since light is incorporeal, its fountain cannot be body, but the pure energy of intellect, illuminating in its proper habitation the middle region of the heavens: and from this exalted situation scattering its light, it fills all the celestial orbs with powerful vigour, and illuminates the universe with divine and incorruptible light. Whatever, likewise, we first perceive by the sight, is nothing but a mere name of honourable labour, unless it receives the ruling assistance of light. For how can any thing be visible, unless, like matter, it is moved to the artificer that it may receive the supervening investments of form? Just as gold in a state of simple fusion is indeed gold, but is not a statue or an image till the artificer invests it with form. In a similar manner all naturally visible objects cease to be apparent, unless light is present with the perceiver. Hence, since it confers vision on the perceiver, and visibility on the objects of perception, it perfects two natures in energy, sight and that which is visible. Perfections, however, are form and essence; though perhaps an assertion of this kind is more subtle than is suited to our present purpose.