ANCIENT PREFACE TO THE READER.

A decorative woodcut border with repeating floral and geometric patterns precedes the heading. A large historiated initial 'P' begins the first paragraph, depicting a figure in a landscape with buildings in the background.

It is my purpose, Reader, to demonstrate in this little book that the Most Good and Greatest Creator, in the creation of this moving world and the arrangement of the heavens, had regard for those (1) five regular bodies Platonic solids: The tetrahedron, cube, octahedron, dodecahedron, and icosahedron; the only five shapes where every face is an identical regular polygon. which have been most celebrated from the time of Pythagoras and Plato down to our own, and that He accommodated the number of the heavens, their proportions, and the system of their motions to the nature of those solids. But before I allow you to come to the matter itself: I shall discuss with you a few things, both regarding the occasion of this little book and the reasoning behind my project, which I have judged to pertain both to your understanding and to my reputation.

Six years ago, while I was studying at Tübingen under the most illustrious Master Michael Maestlin, I was so moved by the manifold inconveniences of the common opinion regarding the world The "common opinion" refers to the Ptolemaic or geocentric system, which placed Earth at the center. that I became greatly delighted with Copernicus, of whom Maestlin made frequent mention in his lectures. Not only did I often defend his views in the physical disputations of the students, but I even wrote a (2) detailed disputation on the primary motion, arguing that it happens because of the Earth's revolution. And I was already at the point where I would also ascribe the motion of the Sun to the (3) Earth—just as Copernicus did with mathematical reasons, I would do with physical or, if you prefer, metaphysical reasons. Toward this end, I gradually collected the advantages which Copernicus has over Ptolemy in mathematics, partly from the words of Maestlin and partly (by my own effort) original: "meo Marte". Joachim Rheticus could have easily freed me from this labor, as he pursued each point briefly and clearly in his First Narrative The Narratio Prima, the first published account of Copernican theory.. Meanwhile, while I was rolling that stone A reference to the Sisyphean task of difficult labor, but with excessive curiosity original: "περιεργως", contrary to Theology: it happened conveniently that I came to Graz and there succeeded Georg Stadius, of pious memory. There, the nature of my office bound me more strictly to these studies. In the explanation of the principles of Astronomy, all those things which I had previously either heard from Maestlin or pursued myself were of great use to me. And as in Virgil, "fame thrives on movement and gains strength as it goes": so the diligent contemplation of these things became the cause of further contemplation. Until finally, in the year 1595, when I desired to spend my leisure time from lectures well and in accordance with my duties, I threw myself with the whole impetus of my mind into this subject.

And there were three things in particular whose causes—why they were so and not otherwise—I persistently sought: the Number, the Quantity In this context, "quantity" refers to the size or distance of the planetary orbits., and the Motion of the spheres. That I dared to do this was brought about by that beautiful harmony of things at rest—the Sun, the fixed stars, and the intermediate space—with God the Father, the Son, and the Holy Spirit: (4) a resemblance which I shall pursue further in the Cosmography. Since things at rest were thus arranged, I did not doubt but that the moving bodies would show themselves to be likewise. At first, I attacked the matter with numbers, and I considered whether one orbit might be double, triple, or quadruple another, or what it might finally be, and how much each orbit differed from another in the Copernican system. I lost a great deal of time in that labor, as if in play, since no equality appeared either in the proportions themselves or in their increases. I perceived no benefit from this, except that I engraved those very distances, as they were set forth by Copernicus, most deeply into my memory. This record of various attempts, Reader, may anxiously toss your assent here and there like the waves of the sea, so that, exhausted, you may finally withdraw all the more gladly to the causes explained in this little book, as if to a safe harbor. Nevertheless, I was comforted from time to time and raised to better hope, both by other reasons which follow below and by the fact that motion always seemed to follow distance; where there was a great gap between orbits, there was also a great gap between their motions. For if (I thought) God adapted the motions to the prescription of the distances for the orbits, surely He also accommodated the distances themselves to the prescription of something.

When, therefore, it did not succeed in this way, I tried an approach by another way, wonderfully bold. (5) Between Jupiter and Mars I interposed a new Planet, and likewise another between Venus and Mercury—two planets which perhaps we do not see because of their smallness—and I assigned to them their orbital original: "περιοδικὰ" periods. For in this way, I thought I would achieve some equality of proportions, which proportions would be decreased in order between pairs toward the Sun, and increased toward the fixed stars; just as the Earth is closer to Venus in the size of the terrestrial orbit than...