[Dialogo] Systema cosmicum … in quo quatuor dialogis, de duobus maximis mundi systematibus, ptolemaico & copernicano, utriusq; rationibus philosophicis ac naturalibus indefinite propositis, disseritur … Accessit appendix gemina, qua SS. Scripturæ dicta cum terræ mobilitate conciliantur.

[Leiden &] Strassburg: David Hautt for Elzevir, 1635.

First Latin edition of the Dialogo, Galileo’s celebrated defence of the Copernican view of the solar system, the most notorious banned book of the 17th century. Written in dialogue form, it “was designed both as an appeal to the great public and as an escape from silence … it is a masterly polemic for the new science. It displays all the great discoveries in the heavens which the ancients had ignored; it inveighs against the sterility, wilfulness, and ignorance of those who defend their systems; it revels in the simplicity of Copernican thought and, above all, it teaches that the movement of the earth makes sense in philosophy, that is, in physics … The Dialogo, more than any other work, made the heliocentric system a commonplace” (PMM). “The Dialogo, far more than any work, convinced men of the truth of the Copernican system” (Gingerich). Pope Urban VIII was not persuaded, however, and immediately convened a special commission to examine the book and make recommendations. In casting the Pope as the simple-minded Aristotelian Simplicius, Galileo brought upon himself arrest, trial by the Inquisition and life imprisonment. The sentence was commuted to permanent house arrest, while the printing of any of his works was forbidden. The Dialogo remained on the index until 1832. This Latin edition was translated at Galileo’s request by Matthias Bernegger (1582-1640), an Austrian from Hallstatt, who had studied in Strassburg, where he settled in 1603. In his preface he explains how he came to translate it, how he had taught himself Italian, and how eventually the Elzeviers, at the urging of the Hebraist Marcus Zuerius Boxhorn and others, persuaded him to undertake the work and agreed to publish it. In addition to rendering the work accessible to a larger audience outside Italy, Bernegger’s translation also includes tracts by Kepler and Foscarini on the compatibility of the Copernican and Christian universes. These tracts were not present in the first edition.

In August 1597, Galileo wrote to Kepler expressing his sympathies for Copernicanism, having received a copy of the Mysterium cosmographicum (1596) from him. At this time Galileo’s support for Copernicus was Earth-based: Galileo had devised a theory of the tides involving the combined rotational motions of the Earth around its axis and, after Copernicus, around the Sun. Everything changed early in 1610 when Galileo first turned a telescope to the skies. Not only was the moon revealed to be mountainous and the Milky Way to consist of separate stars, contrary to Aristotelian principles, but a host of new fixed stars and four satellites of Jupiter were promptly discovered. Galileo’s account of these discoveries was published in the Sidereus nuncius (Venice, 1610). Galileo saw in the satellites of Jupiter a miniature planetary system in which, as in Copernican astronomy, it could no longer be held that all moving heavenly bodies revolved exclusively about the earth. Galileo first spoke out decisively in print for the Copernican hypothesis in his 1613 work on sunspots, Istoria e dimostrazioni intorno alle macchie solari. During its composition he had taken pains to determine the theological status of the idea of incorruptibility of the heavens, finding that this was regarded by churchmen as an Aristotelian rather than a Catholic dogma. But attacks against Galileo and his followers soon appeared in ecclesiastical quarters. These came to a head with a denunciation from the pulpit in Florence late in 1614. A year later Galileo went to Rome (against the advice of his friends and the Tuscan ambassador) to clear his own name and to prevent, if possible, the official suppression of the teaching of Copernicanism. In the first, he succeeded, but on the second he failed: Galileo was instructed on 26 February 1616 to abandon the holding or defending of that view. No action was taken against him, nor were any of his books suspended. Returning to Florence, Galileo took up less theologically controversial topics, culminating in the publication of Il Saggiatore in 1623. Just before it emerged from the press, Maffeo Barberini became pope as Urban VIII. Galileo journeyed to Rome in 1624 to pay his respects to Urban, and secured from him permission to discuss the Copernican system in a book, provided that the arguments for the Ptolemaic view were given an equal and impartial discussion. Urban refused to rescind the edict of 1616, although he remarked that had it been up to him, the edict would not have been adopted.

The Dialogue Concerning the Two Chief World Systems occupied Galileo for the next six years. It has the literary form of a discussion between a spokesman for Copernicus, one for Ptolemy and Aristotle, and an educated layman for whose support the other two strive. Galileo thus remains technically uncommitted except in a preface which ostensibly supports the anti-Copernican edict of 1616. The book will prove, he says, that the edict did not reflect any ignorance in Italy of the strength of pro-Copernican arguments. The contrary is the case; Galileo will add Copernican arguments of his own invention, and thus he will show that not ignorance of or antagonism to science, but concern for spiritual welfare alone, guided the Church in its decision.

“The opening section of the Dialogue critically examines the Aristotelian cosmology. Only those things in it are rejected that would conflict with the motion of the earth and stability of the sun or that would sharply distinguish celestial from terrestrial material and motions. Thus the idea that the universe has a center, or that the earth is located in such a center, is rejected, as is the idea that the motion of heavy bodies is directed to the center of the universe rather than to that of the earth. On the other hand, the Aristotelian concept of celestial motions as naturally circular is not rejected; instead, Galileo argues that natural circular motions apply equally to terrestrial and celestial objects. This position appears to conflict with statements in later sections of the book concerning terrestrial physics. But uniform motion in precise circular orbits also conflicts with actual observations of planetary motions, whatever center is chosen for all orbits. Actual planetary motions had not been made literally homocentric by any influential astronomer since the time of Aristotle. Galileo is no exception; in a later section he remarked on the irregularities that still remained to be explained. Opinion today is divided; some hold that the opening arguments of the Dialogue should be taken as representative of Galileo’s deepest physical and philosophical convictions, while others view them as mere stratagems to reduce orthodox Aristotelian opposition to the earth’s motion.

“Important in the Dialogue are the concepts of relativity of motion and conservation of motion, both angular and inertial, introduced to reconcile terrestrial physics with large motions of the earth, in answer to the standard arguments of Ptolemy and those added by Tycho Brahe. The law of falling bodies and the composition of motions are likewise utilized. Corrections concerning the visual sizes and the probable distances and positions of fixed stars are discussed. A program for the detection of parallactic displacements among fixed stars is outlined, and the phases of Venus are adduced to account for the failure of that planet to exhibit great differences in size to the naked eye at perigee and apogee. Kepler’s modification of the circular Copernican orbits is not mentioned; indeed, the Copernican system is presented as more regular and simpler than Copernicus himself had made it. Technical astronomy is discussed with respect only to observational problems, not to planetary theory.

“To the refutation of conventional physical objections against terrestrial motion, Galileo added two arguments in its favor. One concerned the annual variations in the paths of sunspots, which could not be dynamically reconciled with an absolutely stationary earth. Geometrically, all rotations and revolutions could be assigned to the sun, but their conservation would require very complicated forces. The Copernican distribution of one rotation to the sun and one rotation and one revolution to the earth fitted a very simple dynamics. The second new argument concerned the existence of ocean tides, which Galileo declared, quite correctly, to be incapable of any physical explanation without a motion of the earth. His own explanation happened to be incorrect; he argued that the earth’s double motion of rotation and revolution caused a daily maximum and minimum velocity, and a continual change of speed, at every point on the earth. The continual variation of speed of sea basins imparted different speeds to their contained waters. The water, free to move within the basins, underwent periodic disturbances of level, greatest at their coasts; the period depended on sizes of basins, their east-west orientations, depths, and extraneous factors such as prevailing winds. In order to account for monthly and annual variations in the tides, Galileo invoked an uneven speed of the earth-moon system through the ecliptic during each month, caused by the moon’s motion with respect to the earth-sun vector; for annual seasonal effects, he noted changes of the composition of rotational and revolutional components in the basic disturbing cause.

“The Dialogue was completed early in 1630. Galileo took it to Rome, where it was intended to be published by the Lincean Academy. There he sought to secure a license for its printing. This was not immediately granted, and he returned to Florence without it. While the matter was still pending, Federico Cesi died, depriving the Academy of both effective leadership and funds. Castelli wrote to Galileo, intimating that for other reasons he would never get the Roman imprimatur and advising him to print the book at Florence without delay. Negotiations ensued for permission to print the book at Florence. Ultimately these were successful, and the Dialogue appeared at Florence in March 1632. A few copies were sent to Rome, and for a time no disturbance ensued. Then, quite suddenly, the printer was ordered to halt further sales, and Galileo was instructed to come to Rome and present himself to the Inquisition during the month of October …

“Confined to bed by serious illness, he at first refused to go to Rome. The grand duke and his Roman ambassador intervened stoutly in his behalf, but the pope was adamant. Despite medical certificates that travel in the winter might be fatal, Galileo was threatened with forcible removal in chains unless he capitulated. The grand duke, feeling that no more could be done, provided a litter for the journey, and Galileo was taken to Rome in February 1633.

“The outcome of the trial, which began in April, was inevitable. Although Galileo was able to produce an affidavit of Cardinal Bellarmine to the effect that he had been instructed only according to the general edict that governed all Catholics, he was persuaded in an extrajudicial procedure to acknowledge that in the Dialogue he had gone too far in his arguments for Copernicus. On the basis of that admission, his Dialogue was put on the Index, and Galileo was sentenced to life imprisonment after abjuring the Copernican “heresy.” The terms of imprisonment were immediately commuted to permanent house arrest under surveillance. He was at first sent to Siena, under the charge of its archbishop, Ascanio Piccolomini. Piccolomini, who is said to have been Galileo’s former pupil, was very friendly to him. Within a few weeks he had revived Galileo’s spirits—so crushed by the sentence that his life had been feared for—and induced him to take up once more his old work in mechanics and bring it to a conclusion. While at Siena, Galileo began the task of putting his lifelong achievements in physics into dialogue form, using the same interlocutors as in the Dialogue” (DSB).

“Even as the Dialogue was being banned in Rome, Galileo’s friend Elia Diodati was making plans for an international edition. Diodati recruited Matthias Bernegger, a university professor in Strasbourg, to translate Galileo’s text into Latin, the universal language of European scholarship. Diodati also found a publisher for the book, the Dutch Elzevier firm, one of the most prestigious scholarly publishers in 17th century Europe, based in safely Protestant Leiden. Anticipating an eager audience, the Elzeviers hurried the book into print. Printing (by David Hautt of Strasbourg) was begun while the translation was still ongoing. And the book was published in a large edition of about 600 copies.

“Copies were available for sale by March of 1635. The book bore the new title Systema Cosmicum, but the text was nearly identical to the 1632 Dialogue. One striking difference, however, was the newly engraved frontispiece for the Elzevier edition. As in the Italian edition, the engraving showed Aristotle, Ptolemy, and Copernicus engaged in conversation. In the Italian illustration, all three were elderly and all were equally absorbed in the debate. In the new edition the Greek philosophers were still elderly—Aristotle appeared to be leaning on a cane—but Copernicus was much younger. While Aristotle and Ptolemy focused on the model of the old universe, Copernicus, holding his new model, looked out at the reader, as though appealing directly to the sophisticated, intelligent European of 1635. The banner overhead pays tribute to Galileo’s patron, Ferdinando II de’ Medici, Grand Duke of Tuscany.

“For the editors and publishers of the Systema Cosmicum, the idea of intellectual freedom was as important as the specific arguments about the nature of the universe. The title page of the Elzevier edition prominently featured Galileo’s credentials, and it announced that the two world systems would be evaluated in ‘philosophical and natural’ arguments. It also advertised an appendix in which it would be demonstrated that the Copernican system was compatible with Christian scriptures. The two quotes near the bottom of the page reinforced the theme of intellectual freedom and free inquiry. The first, from the Greek philosopher Alcinous reads: ‘It is necessary for one intending to be a philosopher to be free in thought.’ The second, a quote from Seneca, reads: ‘Especially among philosophers should be equal liberty.’ The verso of the title page listed the Catholic authorities who had originally approved publication of the Dialogue and later reneged. And for good measure, there was another quote from a classical author on the theme of truth triumphing over falsehood.

“A note by translator Matthias Bernegger addressed to the ‘Kind Reader’ described the reasons for publishing a new edition of the Dialogue. Bernegger claimed that the book had been published without Galileo’s knowledge or consent, a patent falsehood intended to protect the author from more persecution. In fact Galileo knew about and enthusiastically supported the project” (https://zsr.wfu.edu/2014/systema-cosmicum-by-galileo-galilei-1635/).

The appended tracts were the introduction to Kepler’s Astronomia nova (1609), and a small tract of 1616 by the Carmelite monk Paolo Antonio Foscarini (1565-1616). Both argued that Christian scripture was not incompatible with the Copernican theory, in part because Biblical teachings were not meant to answer questions about physics and astronomy. “There is some evidence that he and Galileo planned a joint strategy on behalf of heliocentric cosmology. As Galileo wrote his Letter to the Grand Duchess Christina, Foscarini published in Naples a tract entitled Lettera sopra l'Opinione de' Pittagorici, e del Copernico della Mobilità della Terra, e Stabilità del Sole, e del Nuove Pittagorica Systema del Mondo (‘Letter concerning the Opinion of the Pythagoreans and Copernicus about the Mobility of the Earth and Stability of the Sun, and about the New Pythagorean System of the World’), dedicated to the General of the Carmelite Order. In this work, Foscarini defended the Copernican theory as true and defended it against charges that it conflicted with Scripture. With book in hand, Foscarini went to Rome to defend the Copernican theory personally but left Rome before Galileo’s arrival there. Shortly afterward, the consultants of the Holy Office made their pronouncement on the Copernican theory, and as a result Foscarini’s book was placed on the Index (3 March 1616)” (Galileo Project).

The Latin edition of Galileo’s Dialogue was distributed widely throughout Europe. As is generally the case, the controversy surrounding the book only served to pique interest in it. Fierce public debate continued for the next decade, but by the mid-17th century the Copernican model was accepted by most educated Europeans.

Honeyman 1409; Horblit 18c, Dibner 8; Carli-Favaro 32 (148); Caspar 11 (88); Cinti 196 (96); Riccardi I 512; see PMM 128 for the first edition.



4to (198 x 149 mm), pp. [xvi], 495, [xxv], Roman letter, some italic, woodcut initials and headpieces, engraved title depicting Aristotle, Ptolemy, and Copernicus in discussion, Medici arms at head, full-page portrait of Galileo within elaborate frame, by Heyden, numerous woodcut mathematical and geometric diagrams in text including a near full page diagram illustrating the heliocentric system, six-line contemporary marginal note concerning the ‘stabilitatus terrae’ in preface (light age yellowing, the occasional marginal spot). Contemporary speckled calf, spine with raised bands in compartments, richly gilt, all edges speckled red (a little rubbed, upper joint split). An unusually clean copy with good impression of the text – this book is often very browned and poorly printed.

Item #5410

Price: $45,000.00

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