Books

"A LANDMARK IN HUMAN THOUGHT" (PMM). First edition, and an unusually fine copy, of the most important scientific publication of the sixteenth century a "landmark in human thought" (PMM). De revolutionibus was the first work to propose a comprehensive heliocentric theory of the cosmos, according to which the sun stood still and the earth revolved around it. It thereby inaugurated one of the greatest ever paradigm shifts in the history of human thought. "Renaissance mathematicians, following Ptolemy, believed that the moon, sun and five planets were carried by complex systems of epicycles and deferents about the central earth, the fixed pivot of the whole system. In Copernicus s day it was well known that conventional astronomy did not work accurately � Copernicus, stimulated by the free entertainment of various new ideas among the ancients, determined to abandon the fixity of the earth � With the sun placed at the center, and the earth daily spinning on its axis and circling the sun in common with other planets, the whole system of the heavens became clear, simple and harmonious. The revolutionary nature of his theory is evident in his famous diagram illustrating the concentric orbits of the planets [C1v]" (PMM). The work begins with Andreas Osiander s notorious unsigned preface, in which he attempted to placate potential critics of the work by stating that "these hypotheses need not be true nor even probable" all that was necessary was that they should allow astronomers to correctly calculate the motions of the heavenly bodies" (translation from Gingerich, Eye of Heaven, p. 221). Collation as in Horblit; some copies (20 per cent according to Professor Owen Gingerich, compiler of the Copernicus census) contain an errata leaf printed separately and later. Provenance: Brugiere (name eradicated and read with ultraviolet light on fly-leaf); Ex Libris Jacobi Du Roure Doct[oris] Il[lu]str[issim]I (crossed off on title); Early annotations in two hands, one of which sixteenth-century, in red and black adding notes on radices on ff. 150 152 and elsewhere. See Gingerich s Census p.146 for a list of later owners. "The first speculations about the possibility of the Sun being the center of the cosmos and the Earth being one of the planets going around it go back to the third century BCE. In his Sand-Reckoner, Archimedes (d. 212 BCE), discusses how to express very large numbers. As an example he chooses the question as to how many grains of sand there are in the cosmos. And in order to make the problem more difficult, he chooses not the geocentric cosmos generally accepted at the time, but the heliocentric cosmos proposed by Aristarchus of Samos (ca. 310-230 BCE), which would have to be many times larger because of the lack of observable stellar parallax. We know, therefore, that already in Hellenistic times thinkers were at least toying with this notion, and because of its mention in Archimedes s book Aristarchus's speculation was well-known in Europe beginning in the High Middle Ages but not seriously entertained until Copernicus. "European learning was based on the Greek sources that had been passed down, and cosmological and astronomical thought were based on Aristotle and Ptolemy. Aristotle s cosmology of a central Earth surrounded by concentric spherical shells carrying the planets and fixed stars was the basis of European thought from the 12th century CE onward. Technical astronomy, also geocentric, was based on the constructions of eccentric circles and epicycles codified in Ptolemy s Almagest (2d. century CE). "In the fifteenth century, the reform of European astronomy was begun by the astronomer/humanist Georg Peurbach (1423-1461) and his student Johannes Regiomontanus (1436-1476). Their efforts were concentrated on ridding astronomical texts, especially Ptolemy s, from errors by going back to the original Greek texts and providing deeper insight into the thoughts of the original authors. With their new textbook and a guide to.

Nicolaus Copernicus' groundbreaking work on heliocentrism is encapsulated in his seminal book "De revolutionibus orbium coelestium" (On the Revolutions of the Heavenly Spheres). This work, published in 1543, marked a significant departure from the geocentric model that had dominated astronomical thought for centuries. Copernicus proposed that the Sun, rather than the Earth, was at the center of the universe, with the Earth and other planets revolving around it. "De revolutionibus" begins with seven axioms outlining the heliocentric theory. These include the notions that the Earth rotates daily on its axis and revolves annually around the Sun. Copernicus provided detailed mathematical proofs and astronomical observations to support his heliocentric model. He described the motions of the planets more accurately than the Ptolemaic system, which placed the Earth at the center. While still using some elements of the Ptolemaic system, like epicycles, Copernicus significantly simplified the complex system of planetary motions. The publication of "De revolutionibus" is often considered the starting point of the Scientific Revolution. It fundamentally changed the way humanity understood the cosmos and our place within it. Initially, the book did not cause a major stir, but eventually, the Catholic Church condemned it, placing it on the Index of Forbidden Books in 1616 due to its contradiction with the geocentric view supported by the Church. Despite this, Copernicus' heliocentric theory paved the way for later astronomers like Johannes Kepler and Galileo Galilei, who further developed and provided more evidence for the heliocentric model. The book is divided into six parts. Book I outlines the heliocentric theory and provides a general explanation of the universe. Book II covers the principles of spherical astronomy as a basis for the heliocentric theory. Book III discusses the precession of the equinoxes and the apparent motion of the Sun. Book IV focuses on the Moon and its motion. Book V examines the motions of the planets, including retrograde motion. Finally, Book VI discusses the order of the planets and the orbit of the Earth, as well as an explanation of the various phenomena observed from Earth. Nicolaus Copernicus' "De revolutionibus orbium coelestium" was a groundbreaking work that challenged the long-held geocentric model of the universe. By placing the Sun at the center and describing the motions of the planets around it, Copernicus laid the foundation for modern astronomy and the scientific revolution. His work fundamentally altered humanity's understanding of the cosmos and set the stage for future astronomical discoveries. This work is now rare and highly valuable.