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I'

PROP V.

That the Moon hath not any light of her own.

was the fancy of some of the Jews, and more espe

cially of Rabbi Simeon*, that the moon was nothing else but a contracted sun; and that both those planets, at their first creation, were equal both in light and quantity. For, because God did then call them both great lights, therefore they inferred that they must be both equal in bigness. But a while after (as the tradition goes) the ambitious moon put up her complaint to God against the sun, shewing that it was not fit there should be two such great lights in the heavens; a monarchy would best become the place of order and harmony. Upon this, God commanded her to contract herself into a narrower compass; but she being much discontented hereat, replies, What! because I have spoken that which is reason and equity, must I therefore be diminished? This sentence could not chuse but much trouble her; and for this reason was she in great distress and grief for a long space; but that her sorrow might be some way pacified, God bid her be of good chcer, because her privileges and charter should be greater than the sun's; he should appear in the day time only, she both in the day and night; but her melancholy being not satisfied with this, she replied again, That that alas was no benefit; for in the day time she should be either not seen, or not noted. Wherefore, God to comfort her up, promised, that his people the Israelites should celebrate all their feasts and holidays by a computation of her months; but this being not able to content her, she has looked very melancholy ever since; however, she hath still reserved much light of her own.

Others there were, that did think the moon to be a round globe; the one half of whose body was of a bright substance, the other half being dark; and the divers con

*Tostatus in 1 Gen. Hyeron. de sancta fide Hebræomast. l. 2. c. 4.

versions of those sides towards our eyes, caused the variety of her appearances. Of this opinion was Berosus, as he is cited by Vitruvius; and St. Austin† thought it was probable enough. But this fancy is almost equally absurd with the former, and both of them sound rather like fables, than philosophical truths. You may commonly see how this latter does contradict frequent and easy experience; for it is observed, that that spot which is perceived about her middle when she is in the increase, may be discerned in the same place when she is in the full: whence it must follow, that the same part which was before darkened, is after enlightened, and that the one part is not always dark, and the other light of itself. But enough of this; I would be loth to make an enemy, that I may afterwards overcome him, or bestow time in proving that which is already granted; I suppose now, that neither of them hath any patrons, and therefore need no confutation.

It is agreed upon by all sides, that this planet receives. most of her light from the sun; but the chief controversy is, whether or no she hath any of her own? The greater multitude affirm this. Cardan ‡ amongst the rest, is very confident of it; and he thinks that if any of us were in the moon at the time of her greatest eclipse, lunam aspiceremus non secus ac innumeris cereis splendidissimis accensis, atque in eas oculis defixis cæcutiremus; "we should per"ceive so great a brightness of her own, that would blind

us with the mere sight, and when she is enlightened by "the sun, then no eagle's eye (if there were any there) is "able to look upon her." This Cardan says, and he doth but say it, without bringing any proof for its confirmation. However, I will set down the arguments that are usually urged for this opinion, and they are taken either from scripture or reason; from scripture is urged that place, 1 Cor. xv. where it is said, There is one glory of the sun, and another glory of the moon. Ulysses Albergettus urges

* Lib. 9. Architect. De subtil. 1. 3.

+ Narrat. Psalm. item ep. 119.

that in Matth. xxiv. 29. ἡ σεληνην 8 δώσει το φεγγΘ αυτής, the moon shall not give her light: therefore (says he) she hath some of her own.

But to these we may easily answer, that the glory and light there spoken of, may be said to be hers, though it be derived, as you may see in many other instances.

The arguments from reason are taken either,

1. From that light which is discerned in her, when there is a total eclipse of her own body, or of the sun.

2. From the light which is discerned in the darker part of her body, when she is but a little distant from the sun.

1. For when there are any total eclipses, there appears in her body a great redness, and many times light enough to cause a remarkable shade, as common experience doth sufficiently manifest: but this cannot come from the sun, since at such times either the earth or her own body shades her from the sun-beams; therefore it must proceed from her own light.

2. Two or three days after the new moon, we may perceive light in her whole body, whereas the rays of the sun reflect but upon a small part of that which is visible; therefore it is likely that there is some light of her own.

In answering to these objections, I shall first shew, that this light cannot be her own; and then declare that which is the true reason of it.

That it is not her own, appears,

1. Because then she would always retain it; but she has been sometimes altogether invisible, when as notwithstanding some of the fixed stars of the fourth or fifth magnitude might easily have been discerned close by her: as it was in the year 1620*.

2. This may appear likewise from the variety of it at divers times; for it is commonly observed that sometimes it is of a brighter, sometimes of a darker appearance; now redder, and at another time of a more duskish colour. The observation of this variety in divers eclipses, you may

* Keplar ep. Astron. cop. l. 6. p. 5. sect. 2.

see set down by Keplar and many others*. But now this could not be, if that light were her own, that being constantly the same, and without any reason of such an alte-, ration so that thus I may argue.

If there were any light proper to the moon, then would that planet appear brightest when she is eclipsed in her perige, being nearest to the earth; and so consequently more obscure and duskish when she is in her apoge or farthest from it; the reason is, because the nearer any enlightened body comes to the sight, by so much the more strong are the species, and the better perceived. This sequel is granted by some of our adversaries, and they are the very words of noble Tycho; Si lana genuino gauderet lumine, utique cum in umbra terræ esset, illud non amitteret, sed eo evidentius exerceret; omne enim lumen in tenebris, plus splendet cum alio majore fulgore non præpeditur ↑. If the moon had any light of her own, then would she not lose it in the earth's shadow, but rather shine more clearly; since every light appears greater in the dark, when it is not hindered by a more conspicuous brightness.

But now the event falls out clean contrary, (as observation doth manifest, and our opposites themselves do grant) the moon appearing with a more reddish and clear light when she is eclipsed, being in her apoge or farthest distance, and a more blackish iron colour when she is in her perige or nearest to us, therefore she hath not any light of her own. Nor may we think that the earth's shadow can cloud the proper light of the moon from appearing, or take away any thing from her inherent brightness; for this were to think a shadow to be a body, an opinion altogether misbecoming a philosopher, as Tycho grants in the fore-cited place, Nec umbra terræ corporeum quid est, aut densa aliqua substantia, ut lunæ lumen obtenebrare possit, atque id visui nostro præripere, sed est quædam privatio luminis solaris, ob interpositum opacum corpus terræ.

* Opt. astron. c. 7. num. 3. + De nova stella. 1. 1. c. 10. Reinold Comment. in Purb. Theor. p. 164.

Nor is the earth's shadow any corporeal thing, or thick substance, that it can cloud the moon's brightness, or take it away from our sight; but it is a mere privation of the sun's light by reason of the interposition of the earth's opacous body.

3. If she had any light of her own, then that would itself be either such a ruddy brightness as appears in the eclipses, or else such a leaden duskish light, as we see in the darker parts of her body, when she is a little past the conjunction. (That it must be one of these, may follow from the opposite arguments;) but it is neither of these, therefore she hath none of her own.

1. It is not such a ruddy light as appears in eclipses; for then why can we not see the like redness, when we may discern the obscurer parts of the moon?

You will say, perhaps, that then the nearness of that greater light takes away that appearance.

I reply, This cannot be. For then, why does Mars shine with his wonted redness, when he is near the moon? Or why cannot her greater brightness make him appear white, as the other planets? Nor can there be any reason given, why that greater light should represent her body under a false colour.

2. It is not such a duskish leaden light, as we see in the darker part of her body, when she is about a sextile aspect distant from the sun; for then, why does she appear red in the eclipses; since mere shade cannot cause such a variety? For it is the nature of darkness, by its opposition, rather to make things appear of a more white and clear brightness, than they are in themselves. Or, if it be the shade, yet those parts of the moon are then in the shade of her body, and therefore in reason should have the like redness. Since, then, neither of these lights are hers; it follows, that she hath none of her own. Nor is this a singular opinion, but it hath had many learned patrons: such was Macrobius*, who being for this quoted of Rho

*Somn. Scip. 1. 1. c. 20. Lect, antiq. 1. 1. c. 15.

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