I understand, said she; we don't allow them to penetrate into the heart of our vortex, and mix with our planets; we receive them as the Grand Signior receives the ambassadors that are sent to him. He does not honour them with a lodging in Constantinople, but assigns them one in the environs. There is another point of resemblance, I replied, between us and the Ottomans: they receive ambassadors without sending any in return; and we receive the comets without sending any of our planets to return their visits.
From all these circumstances, answered she, we seem to be very proud: yet we should not hastily form that conclusion; these strange planets have a very menacing air with their beards and trains; perhaps they are only sent to insult us; ours not having so imposing an appearance would not be so well calculated to inspire those worlds with awe. The tails and beards, I replied, are merely extraneous: the planets themselves do not differ from ours; but in entering our vortex they assume the beard or train from a certain illumination derived from our sun. This, by the bye, has not been very well explained by our astronomers; however, they are sure it is only some sort of illumination, and they must tell us more of it when they can. Then I wish, rejoined she, that our Saturn would take a beard or a tail, and frighten the other vortices; then laying aside his terrific appendages, return to us and perform his ordinary functions. He would do better to stay where is, answered I. You recollect I explained to you the shock produced by the repulsive power of each vortex: I think a poor planet must be violently shaken in such a situation, and the inhabitants cannot feel much the better for passing through it. We think ourselves vastly unfortunate when a comet makes its appearance, whereas we ought to consider the comet most unfortunate. I am not inclined to pity it, said the Marchioness; I dare say all its inhabitants arrive here in good health, and it must be extremely entertaining to them to go into a new vortex. We who always remain in our own have but a dull life. If the people in a comet have the sense to know the time at which they shall pass into our vortex, those who have already been the journey, are just before busily employed in describing to the rest what they will see. Speaking of Saturn, they say: "You will presently see a planet with a great ring round it. Then, you will discover one followed by four small planets." Some of these people, perhaps are set to watch the moment of entering our system: when it is arrived they cry new sun, new sun, as our sailors exclaim land, land.
I find then, said I, it is useless to attempt raising your compassion for the comets: I hope, however, you will not refuse it to the inhabitants of a vortex whose sun has been extinguished, and who are thus condemned to perpetual darkness. Suns extinguished? cried she. Yes, undoubtedly, I replied. The ancients saw certain fixed stars which are no longer visible.[54] These suns have been deprived of their light: ruin must have ensued throughout the vortex; a general mortality on all the planets; for how could existence be maintained without the sun? The thought is too dreadful, said she; is it not possible to evade it? I'll tell you, answered I, what some very intelligent people have imagined. They think that the fixed stars that have disappeared are not extinct, but partly darkened; that is to say, that they have one side obscure; the other luminous: that as they turn on themselves, they first present the light part to us, and then the dark, when that is the case we cease to see them. Apparently the fifth moon belonging to Saturn is in this condition, for during one part of its revolution we entirely lose sight of it; at which time it is not most remote from the earth; on the contrary, it is then sometimes nearer than when visible. Though this moon is a planet, and therefore cannot exactly guide our opinion with respect to suns, yet we may suppose that a sun can be partly covered by fixed spots. To spare you the pain of believing the other opinion, we will adopt this, which is more agreeable: but I can only receive it when applied to such fixed stars as have a regular time for appearing and disappearing, as some have lately been observed to do, otherwise we cannot suppose them half suns. What must we say to the stars that disappear, and do not become visible after a time that would certainly have been sufficient for turning on their axis? You are too just to require me to believe that they are half suns: however I will do all in my power to serve you; we will conclude that these stars are not extinguished, but plunged in the unfathomable depth of the sky, and thus become invisible; in this case the vortex would accompany its sun, and all go on as usual. It is true that the greatest part of the fixed stars have not any motion which removes them farther from us, for if they were not always equally distant, they would sometimes appear larger, sometimes smaller; but that is not the case.
[54] In 1572 and 1604, some beautiful stars appeared to burst into light, and afterwards become extinct. Astron. Art. 792.
We will therefore suppose that some of the small vortices, being light and active, slip betwixt the others, and return after they have made their tour, whilst the larger systems remain immoveable. But there is one inevitable misfortune: there are some fixed stars, which for a long time are alternately visible and invisible, and at length totally disappear. Half suns would re-appear at a regular time; others that had retreated to an immense distance would at once disappear, and be concealed for a very long time: exert therefore all your resolution, madam; these stars are certainly suns which grow so dark as to be invisible to us, then resume their brightness, and afterwards are entirely extinguished. How, exclaimed the Marchioness, can a sun, a source of light, become darkened? With the greatest ease, answered I, if Descartes be in the right. He imagines that the spots on our sun, being impurities, or vapours, may grow thick, collect together, form themselves into a mass, and continue to encrust the sun till it is quite hid. If, the sun is a fire connected with a solid matter, serving as its aliment, we are not in a better condition; the solid matter may be consumed. 'Tis said we have already had a fortunate escape: the sun during several years, (the year, for instance, after the death of Cæsar;) appeared very pale; owing to the encrustation which was beginning to form. The sun had sufficient force to break and disperse it; had it continued, we should have been lost. You make me tremble, said the Marchioness. Now I know the consequences of paleness in the sun, instead of going to my glass every morning to see if I am pale, I think I shall go and look whether the sun is so. Take courage, madam, I replied, it requires a good deal of time to ruin a system of worlds. But, answered she, it seems as if time would inevitably effect it. I cannot take upon me to deny it, said I. The immense mass of matter which composes the universe is in continual motion, even the smallest particles of it, and since there is this motion we are in danger, for changes must happen, either slowly or rapidly, but always in a time proportioned to the effect. The ancients were so vastly wise as to imagine the heavenly bodies were of such a nature as never to alter, because they had not observed any alteration in them. Had they leisure to assure themselves of this by experience? Compared with us the ancients were young: if flowers that last but a day were to transmit their histories to each other, the first would draw the resemblance of their gardener in a certain way; after fifteen thousand ages of these flowers had elapsed, others would still describe him in the same manner. They would say; "We have always had the same gardener, the memoirs composed by our ancestors prove this to be the case; all their representations exactly apply to him; surely he is not mortal like us; no change will ever take place in him." Would the reasoning of these flowers be conclusive?—it would have a better foundation than that of the ancients respecting the celestial bodies; and had there never to this day been observed any change in the heavens, though they should appear likely to remain much longer without alteration, I would not yet decide on them; I should think more experience necessary. Should the term of our existence, which is but a moment, be the measure for other durations? Ought we to assert that what has lasted a hundred thousand times longer than we, must last for ever? No, ages on ages of our duration would scarcely be any indication of immortality. Truly, said the Marchioness, I think these worlds can have no pretensions to it. I shall not do them the honour to compare them with the gardener who outlives so many transient flowers; they are but as those flowers themselves, springing up and fading away, one after another: for I suppose, if old stars disappear, new ones become visible; the species cannot otherwise be continued. Yes, answered I, we need not fear the extinction of the species. Some will tell you these new stars are only suns which re-approach us after having been for a long time at a distant part of the heavens. Others think they are suns that have broken through the crust that began to cover them. I easily conceive the possibility of all this; but I think it equally possible for new suns to be created. Why should not the matter that is fit to compose a sun, after having been dispersed in various places, be at length gathered together in one spot and then become the foundation of a new system of worlds? I am the more inclined to this opinion because it answers better to the grand idea I entertain of the works of nature. Has she no way of producing and destroying plants and animals but by a continual revolution? I am persuaded, and I doubt not that by this time you are so too, that she exerts the same power with respect to the worlds. But on such subjects we can only form conjectures. The fact is that for nearly a century past, in which, by the help of telescopes, almost a new heaven has been discovered, unknown to the ancients, there have been few of the constellations in which some sensible alteration has not taken place;[55] the greatest number of changes is observed in the milky-way, as if more motion and bustle existed among this heap of worlds. Really, said the Marchioness, I find the worlds, in short all the heavenly bodies, so liable to change that I have quite overcome the horror I felt at the idea of the suns being extinguished. Well, replied I, to prevent you from relapsing, we will say no more about them, we are arrived at the uppermost part of the heavens, and to inform you whether there are any stars beyond that, exceeds my skill. You may place more worlds or not; just as you are disposed. These invisible countries should, in propriety, be left to the philosophers: they may imagine them to exist, or not exist, or to exist in any way they chuse. I shall content myself with having directed your mind to all that is discernible by your sight.
[55] This is not proved.
Ah! she exclaimed, then I am acquainted with the whole system of the universe! how learned I am! Yes, said I, you are learned enough in all reason, and your knowledge is attended with this convenience,—you may extract your belief of all I have told you whenever you think proper. I only ask as a reward for my trouble, that whenever you see the sun, the sky, and the stars, you will think on me.[56]
[56] As I have given these conversations to the public, I think it would not be right to conceal any thing which passed on the subject I shall publish another dialogue of the same kind that we had a long while after these. It shall be entitled the "Sixth Evening," as the rest were evening scenes.
