‘It is kind of you, Lucius,’ I said, ‘to clothe this absurdity in sounding terms. That is not how our comrade dealt with it. He said the truth, that it is a slap in the face to the moon when they fill her with smuts and blacks, addressing her in one breath [Sidenote: 922] as Artemis and Athena,[308] and in the very same describing a caked compound of murky air and charcoal fire, with no kindling or light of its own, a nondescript body smoking and charred like those thunderbolts which poets[309] address as “lightless” and “sooty”. That a charcoal fire, such as this school makes out the moon to be, has no stability or consistence at all, unless [Sidenote: B] it find solid fuel at once to support and to feed it, is a point not so clearly seen by some philosophers as it is by those who tell us in jest that Hephaestus has been called lame because fire progresses no better without wood than lame people without a stick! If then the moon is fire, whence has it all this air inside it? For this upper region, always in circular motion, belongs not to air but to some nobler substance, which has the property of refining and kindling all things. If air has been generated, how is it that it has not been vaporized by the fire and passed away into some other form, but is preserved near fire all this time, like a nail fitted into the same place and wedged there for ever? If it is rare and diffused, [Sidenote: C] it should not remain stable, but be displaced. On the other hand, it cannot subsist in a solidified form, because it is mingled with fire, and has neither moisture with it nor earth, the only agents by which air can be compacted. Again, rapid motion fires the air which is contained in stones, and even in cold lead, much more then that which is in fire, when whirled round with such velocity. For they are displeased with Empedocles, when he describes the moon as a mass of air frozen like hail and enclosed within her globe of fire. Yet they themselves hold that the moon is a globe of fire which encloses air variously distributed, and this though they do not allow that she has [Sidenote: D] clefts in herself, or depths and hollows (for which those who make her an earth-like body find room), but clearly suppose that the air lies upon her convex surface. That it should do so is absurd in point of stability, and impossible in view of what we see at full moon; for we ought not to be able to distinguish black parts and shadow then; either all should be dull and shrouded, or all should shine out together when the moon is caught by the sun. For look at our earth; the air which lies in her depths and hollows, where no ray penetrates, remains in shadow unilluminated; that which is outside, diffused over the earth, has light and brilliant colouring, because from its rarity it easily mingles, and takes up any quality or influence. [Sidenote: E] By light, in particular, if merely touched, or, in your words, grazed, it is changed all through and illumined.