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The Precursor.] original: "Prodromus." This was the first word of the original 1596 title, indicating it was a "forerunner" to more research. After I entered the study of philosophy at the age of 18, in the year of Christ 1589, the Exoteric Exercises of Julius C. Scaliger Julius Caesar Scaliger (1484–1558) was a famous physician and scholar. His "Exercises" were a standard textbook on natural history and physics in the 16th century. were frequently in the hands of us young students. Taking the opportunity provided by that book, I began to successively devise various ideas on different questions, such as the Heavens, Souls, Spirits, the Elements, the nature of fire, the origin of springs, the ebb and flow of the sea the tides, the shape of the continents and the seas between them, and similar matters. But when this discovery of the proportion of the celestial spheres Kepler’s theory that the distances between planets are governed by the geometry of the five Platonic solids. appeared so extraordinary to me, I decided I should not wait until it could traverse all parts of nature. Nor did I think this discovery should be published in passing, thrown into a heap of other questions that rely only on slight probability. Rather, it pleased me to make the publication of this discovery the beginning of my dissertations; and I dared to hope for similar success in all my other inquiries. But I hoped in vain. For the Heavens—the very beginning of God’s works—possess a far more excellent adornment than these other small and cheap things. Thus, while the Precursor was indeed remarkable, no After-runner original: "Epidromus." Kepler intended to write a sequel titled "Epidromus" covering his other theories, but they didn't meet his scientific standards. followed as I had then proposed, because I was by no means as satisfied with myself regarding those other questions. However, the reader may take my other astronomical works, and especially my books on the Harmonies Kepler’s Harmonices Mundi (1619), which he considers the true fulfillment of his early work., as the genuine and proper "After-runner" to this small book. This is because both follow the same path; that earlier path was established well enough, and has now become a well-trodden road. What was then brief and did not reach its goal is continued in the Harmonies, where the chariot is driven right to the finish line. Such was the Precursor: the first voyage of Amerigo Vespucci; such are the After-runners: the modern annual voyages to America.
The Cosmographic Mystery.] original: "Mysterium Cosmographicum." There exist among the Germans various "Cosmographies," such as those by Münster Sebastian Münster (1488–1552), author of the vastly popular Cosmographia, which combined history, geography, and science. and others, where they indeed begin with the whole world and the celestial parts, but these are finished in a few short pages; the main bulk of the book instead comprises descriptions of regions and cities. Thus, common people use the word Cosmography to mean Geography. Because of this, the term—even though derived from the "world" From the Greek kosmos (world/order).—deceived the bookshops and those who write library catalogs, leading them to list my book among geographical works. However, I used the word Mystery to mean a Secret original: "Arcano.", and I promoted this discovery as such; for indeed, I had never read such things in the book of any other philosopher.
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