I may, I think, suppose, that you know so much of Opticks as to understand, that all visible Objects apparently decrease in Magnitude, as their Distance from the Eye increases. Consequently, that, if the Moon's Orbit was placed as far again from the Earth as it really is, her Globe, or rather _Disk_, would then seem to be but half as big as to us she now appears to be, and of course still farther, were she placed at ten times the Distance she is known to revolve at, her apparent Diameter would be reduced to a tenth Part only of what it now appears to be in her present Orbit, that is, one hundred Times less in visible Magnitude than her neighbouring Disk is found to be where it now is seen. And such, but something less, the two Planets _Venus_ and _Jupiter_, which are frequently, in their Turns, our Morning and Evening Stars, appear to be through a common Telescope. Now these two Planets, together with the other three, which we find moving in regular Orbits round the Sun, are all found subject to the same [N]Changes of _Phænomena_, in their various Aspects with the Sun; and who can doubt but that they are all of the same or like Nature? But you'll say, perhaps, how are we sure that _Venus_ and _Jupiter_ have no native Light of their own, since many of the ancient Philosophers, and in particular _Anaximander_, allowed even the Moon to have some; and besides, in Philosophy, as well as in Logick, I think you hold there is no proving a Negative, at least at such a Distance. [Footnote N: _Venus_ and _Mercury_ in every Heliocentrick Revolution, perform all the Changes of our Moon in a like Gradation and Defection of Light, both horned and gibos'd.] To make you conceive the Impossibility of such a Light, and next to a Demonstration, convince you of the Unnaturalness of such a Supposition, I must put you in mind, that some time ago, when I was last in the Country with you, I think it was about the latter End of Autumn, near the Winter Solstice, as we were walking one Evening, I bid you take notice of the Moon, which was then near setting, and about two Days old. You may remember, her whole Globe appeared to us very conspicuously within a manifest Circle. You immediately told me, that that kind of Phænomenon the Country People called a _Stork_, or the old Moon in the new one's Arms. This I then endeavoured to explain to you, and I think made you sensible it was intirely an Effect of the Earth's, and an Appearance always to be expected at that Time of the Year. The Earth being then in the State of a Full-Moon to that Part of the lunar Orbit, and near her Perihelion, at which time, the Earth sends back a Reflection to the [O]Moon twenty-five times more potent than that of the Moon to us. [Footnote O: Their Diameters being nearly as 1 to 5.]