THE Author of the following Letters having been flattered into a Belief, that they may probably prove of some Use, or at least Amusement to the World, he has ventured to give them, at the Request of his Friends, to the Publick. His chief Design will be found an Attempt towards solving the Phænomena of the Via Lactea, and in consequence of that Solution, the framing of a regular and rational Theory of the known Universe, before unattempted by any. But he is very sensible how difficult a Task it is to advance any new Doctrine with Success, those who have hitherto attempted to propagate astronomical Discoveries in all Ages, have been but ill rewarded for their Labours, tho' finally they have proved of the greatest Benefit and Advantage to Mankind. This ungrateful Lesson we learn from the Fate of those ingenious Men, who, in ignorant Times, have unjustly suffered for their superior Knowledge and Discoveries; they who first conceived the Earth a Ball, were treated only with Contempt for their idle and ridiculous Supposition, as it was called; and he who first attempted to explain the Antipodes, lost his Life by it; but in this Age Philosophers have nothing to fear of this sort, the great Disadvantages attending Authors now, are of a widely different Nature, rising from the infinite Number of Pretenders to Knowledge in this Science, and much is to be apprehended from improper Judges, tho' from real ones nothing; for nothing is more certain than this, as much as any Subject exceeds the common Capacity of Readers, so much will the Work in general be condemned; the Air of Knowledge is at least in finding Fault, and this vain Pretence generally leads People, who have no real Foundation for their Judgment to argue from, to ridicule what they are too sensible they do not understand. Thus the same Disadvantages too often attend both in publick and private an exceeding good Production equally the same as a very bad one: But the Author is not vain enough to think this Work without Faults, has rather Reason to fear, from the Weakness of his own Capacity, that there may be many; but he hopes the Design of the Whole will, in some measure, plead for the Imperfection of the Parts, if the Merits of the Plan should be found insufficient for his full Pardon, in attempting so extensive a Subject.
In a System thus naturally tending to propagate the Principles of Virtue, and vindicate the Laws of Providence, we may indeed say too little, but cannot surely say too much; and to make any further Apology for a Work of such Nature, where the Glory of the Divine Being of course must be the principal Object in View, would be too like rendering Virtue accountable to Vice for any Author to expert to benefit by such Excuse. The Motive which induces us to the Attempt of any Performance, where no good Reason can be supposed to be given for the Omission, or Neglect of it, will always be judged an unnecessary Promulgation, and consequently every Attempt towards the Discovery of Truth, the Enlargement of our Minds, and the Improvement of our Understandings will naturally become a Duty. If therefore this Undertaking falls short of being instrumental towards the advancing the Adoration of the Divine Being in his infinite Creation of higher Works, and proves unable to answer all Objections that may possibly arise against it, yet will its Imperfections appear of such a Nature to every candid Reader, as to afford the Author a sufficient Apology for producing them to the World: And it is to be hoped farther, that where a Work is entirely upon a new Plan, and the Beginning, as it were, of a new Science, before unattempted in any Language, the Author having dug all his Ideas from the Mines of Nature, is surely entitled to every kind of Indulgence.
To those who are weak enough to think that such Enquiries as these are over-curious, vain, and presumptive, and would willingly, suitable to their own Ignorance and Comprehension, set Bounds to other People's Labours, I answer with Mr. Huygens, "That if our Forefathers had been at this Rate scrupulous, we might have been ignorant still of the Magnitude and Figure of the Earth; or that there was such a Place as America. We should not have known that the Moon is enlightened by the Sun's Rays, nor what the Causes of the Eclipses of each of them are; nor a Multitude of other Things brought to Light by the late Discoveries in Astronomy; for what can a Man imagine more abstruse, or less likely to be known, than what is now as clear as the Sun."