Galileo Galilei and the Roman Curia/Chapter 8

by Karl von Gebler

CHAPTER VIII.

THE CONTROVERSY ON COMETS.

Studious Seclusion.—Waiting for the Correction of the Work of Copernicus.—Treatise on Tides.—Sends it to Archduke Leopold of Austria.—The Letter which accompanied it.—The three Comets of 1618.—Galileo's Opinion of Comets.—Grassi's Lecture on them.—Guiducci's Treatise on them inspired by Galileo.—Grassi's "Astronomical and Philosophical Scales."—Galileo's Reply.—Paul V.—His Death.—Death of Cosmo II.—Gregory XV.—"Il Saggiatore" finished.—Riccardi's "Opinion" on it.—Death of Gregory XV.—Urban VIII.

Seven years passed by, during which Galileo lived a secluded and studious life in the Villa Segni, at Bellosguardo, near Florence, without publishing any new work. How could he do so? The acceptance and further application of the Copernican system was the mainspring of all his scientific pursuits, of which, multifarious as they were, the principle of the double motion of the earth was both foundation and keystone. The general permission to employ the theory as a working hypothesis was of little service to him. The lofty structure of correct knowledge of our universe could not be raised on a pedestal of sand; it required the imperishable marble of truth. Galileo was compelled to withhold the results of his researches until, perchance, some altered state of things should change the mind of the papal court, at present so inimical to the Copernican cause. The publication of any researches in accordance with the Copernican system appeared especially dangerous, until the promised corrections had been made in the famous work of the Canon of Frauenburg, which had been temporarily placed on the Index. These corrections would give more precise information as to how they wished the new doctrine handled at Rome, what limits had been set by ecclesiastical despotism to researches into nature. Galileo watched with great anxiety the labours of the papal censors, and tried to hasten them through his friend Prince Cesi.^[1] This eager interest in the earliest possible publication of the corrections is another thing which does not accord with the assumed stringent prohibition of February 26th. What difference would it have made to Galileo whether any facilities were offered for the discussion of the Copernican theory or not, if absolute silence on the subject had been enjoined on him?

During this period, when he could not venture to have the results of his various researches published, he was careful to make them known to some friends of science by means of long letters, numerous copies of which were then circulated in Europe. Very few of them, unfortunately, have come down to us, but there is one of them that deserves special notice. It indicates precisely Galileo's position: on the one hand he feels constrained to make way for the recognition of the truth; but on the other, as a good Catholic, and from regard to his personal safety, he does not wish to clash with ecclesiastical authority. This letter, too, adds weight to the conclusion that there was no prohibition enjoining absolute silence on the Copernican theory on Galileo.

During his last stay at Rome, at the suggestion of Cardinal Orsini, he had written a treatise on the tides in the form of a letter to that dignitary, dated January 8th,^[2] in which he expressed his firm conviction, erroneously as we now know, that this phenomenon could only be explained on the theory of the double motion of the earth. He represented it as an important confirmation of the truth of it. In May, 1618, he sent a copy of this treatise to the Archduke Leopold of Austria, who was friendly to him, and was a brother of the Grand Duchess. But as since it was written the decree of March 5th had been issued, which only permitted discussion of the subject as a hypothesis, Galileo thought it advisable to add a sort of accompaniment to his treatise, in which he took the utmost pains to comply with the conditions imposed by the Church on her dutiful and orthodox son. He wrote:—

"With this I send a treatise on the causes of the tides, which I wrote rather more than two years ago at the suggestion of his Eminence Cardinal Orsini, at Rome, at the time when the theologians were thinking of prohibiting Copernicus's book and the doctrine enounced therein of the motion of the earth, which I then held to be true, until it pleased those gentlemen to prohibit the work, and to declare that opinion to be false and contrary to Scripture. Now, knowing as I do, that it behoves us to obey the decisions of the authorities, and to believe them, since they are guided by a higher insight than any to which my humble mind can of itself attain, I consider this treatise which I send you merely to be a poetical conceit, or a dream, and desire that your Highness may take it as such, inasmuch as it is based on the double motion of the earth, and indeed contains one of the arguments which I have adduced in confirmation of it. But even poets sometimes attach a value to one or other of their fantasies, and I likewise attach some value to this fancy of mine. Now, having written the treatise, and having shown it to the Cardinal above-mentioned, and a few others, I have also let a few exalted personages have copies, in order that in case any one not belonging to our Church should try to appropriate my curious fancy, as has happened to me with many of my discoveries, these personages, being above all suspicion, may be able to bear witness that it was I who first dreamed of this chimera. What I now send is but a fugitive performance; it was written in haste, and in the expectation that the work of Copernicus would not be condemned as erroneous eighty years after its publication. I had intended at my convenience, and in the quiet, to have gone more particularly into this subject, to have added more proofs, to have arranged the whole anew, and to have put it into a better form. But a voice from heaven has aroused me, and dissolved all my confused and tangled fantasies in mist. May therefore your Highness graciously accept it, ill arranged as it is. And if Divine love ever grants that I may be in a position to exert myself a little, your Highness may expect something more solid and real from me."^[3]

On reading such passages one really does not know which to be the most indignant at,—the iron rule by which a privileged caste repressed the progress of science in the name of religion, or the servility of one of the greatest philosophers of all times in not scorning an unworthy subterfuge in order to disseminate a grain of supposed truth in the world without incurring personal danger.

But in spite of all precautions, in spite of "chimeras," "fictions," "fantasies," and even "the voice from heaven," the circulation of this treatise, based upon the theory of the double motion, would have been an infringement of the assumed absolute prohibition to Galileo, while, thanks to the ingenious accompaniment, it in no way clashed with the decree of 5th March. Galileo's conduct shows plainly enough that he humbly submitted to the ecclesiastical ordinance, but there is not a trace of the prohibition to discuss the doctrine "in any way."

Little, however, as Galileo desired to engage, thus hampered, in any perilous controversies, the next time it was nature herself who enticed him into the field in which his genius and his polemical ingenuity acquired for him both splendid triumphs and bitter foes.

In August, 1618, three comets appeared in the heavens, and the brilliant one in the constellation of the Scorpion strongly attracted the attention of astronomers. Although it was visible until January, 1619, Galileo had very little opportunity of observing it, as he was confined to his bed by a severe and tedious illness.^[4] But he communicated his views on comets to several of his friends, and among others to the Archduke Leopold of Austria, who had come to see the sick philosopher.^[5] He did not consider them to be real heavenly bodies, but merely atmospheric appearances, columns of vapour which rise from earth to the skies, to a very considerable height, far beyond the moon, and become temporarily visible to the inhabitants of the earth, in the well-known form of a comet, by the refraction of the sun's rays. As he judged comets to be without substance, and placed them on a par with mock suns and the aurora borealis, he concluded that they could have no parallax determinations.

In the same year, 1619, a Jesuit, Father Grassi, delivered a lecture on the three comets in the Roman College, in which he gave out that such phenomena were not mere appearances, but real heavenly bodies; copies of this lecture were widely circulated, and Galileo was strongly urged by his adherents to publish his opinion. He was prudent enough to evade for the time a fresh controversy, which, in the existing critical state of affairs, might bring him into danger, and apparently took no part in the scientific feud which was brewing. But he induced his learned friend and pupil, Mario Guiducci, consul of the Academy at Florence, to publish a treatise on comets. Numerous alterations and additions, however, which are found in the original MS. in the Palatina Library at Florence, attest that he had a direct share in the editorship.^[6] The opinions hitherto held by philosophers and astronomers on this subject were discussed, and the author's own—that is Galileo's—expounded. Grassi's views were sharply criticised, and he was reproachfully asked why he had passed over Galileo's recent astronomical discoveries in silence.

Grassi, who recognised the real originator of the work, in the reply which he issued a few months later entirely ignored the pupil, that he might the more vigorously attack the master. Under the pseudonym of Lothario Sarsi Sigensano, he published a pamphlet against Galileo, entitled, "The Astronomical and Philosophical Scales."^[7] It is written with caustic bitterness, and is a model of Jesuitical malice and cunning. The comet question was for the time a secondary matter with Grassi, and he begins with a personal attack on Galileo, by disputing the priority of several of his most important discoveries and inventions, and reproaching him, with pious indignation, with obstinate adherence to a doctrine condemned by theologians. Up to this point he is only angry and spiteful, but as he goes on he becomes cunning. He sets up for a warm defender of the Peripatetic physics, and attacks the Copernican system, and its advocate Galileo, to compel him either to ignominious silence or dangerous demonstrations. Under pretext of meeting Guiducci's reproach that he (Grassi) had taken Tycho as his authority, he asks whether it would have been better to follow the system of Ptolemy, which had been convicted of error, or that of Copernicus, which every God-fearing man must abhor, and his hypothesis, which had just been condemned? In discussing the causes of the movements of comets, it seemed to him that the arguments were insinuated on which the forbidden doctrines were based. "Away!" he exclaims in righteous indignation, "with all such words so offensive to truth and to every pious ear! They were prudent enough certainly scarcely to speak of them with bated breath, and not to blazon it abroad that Galileo's opinion was founded upon this pernicious principle."

Thus attacked, Galileo prepared to defend himself. The greatest caution was necessary, for Grassi was backed by the powerful party of the Jesuits, who made a great boast of this work.^[8] The letters of this period from Prince Cesi and Galileo's ecclesiastical friends at Rome show that they were very anxious that he should not make the influential order of Jesuits his enemies by a direct collision with them. But as they saw the absolute necessity of a reply, they gave him all sorts of good advice, how to parry the attack without incurring their hatred. They were of opinion that he should not honour an adversary concealed behind a pseudonym with a reply written by himself, but should depute the task to a pupil, or, if he intended to conduct his defence in person, clothe his reply in the form of a letter instead of a treatise, not addressed to Sarsi himself, but to one of his own party.^[9] He decided for the latter; and adopting a hint from Mgr. Ciampoli,^[10] he addressed the reply to Mgr. Cesarini, one of his most devoted friends and dauntless defenders.

But the completion of this afterwards famous rejoinder was delayed for two years, and its publication, which, according to custom with all works by members of the Accadémia dei Lincei, was undertaken by the Society, was delayed fully another year owing to the scruples of Prince Cesi and other "lynxes." Galileo's procrastination is to be explained partly by his continued ill health, but more so by the position of affairs at Rome as well as in Tuscany, which was by no means encouraging for a contest with a Jesuit.

The imperious Paul V. was still the reigning Pope, and his good will towards Galileo would certainly only have lasted so long as he was entirely submissive. His dialectic reply, which was pervaded by cutting irony aimed at a father of the order of Jesuits, even sometimes making him appear ridiculous, could not have been much to the taste of a Pope to whom the inviolability of the Church and her ministers was all in all. It is characteristic of this pontiff that, as appears from the negotiations with James I., he seriously claimed the right of deposing kings, and called every attempt to make him relinquish this claim "a heretical proceeding," and pronounced the writings of some Venetian ecclesiastics who disputed it, to be worse than Calvinistic. Just as this stern pontiff was gathered to his fathers (16th January, 1621), in consequence of an attack of apoplexy on the occasion of the celebration of the victory on the Weissenberg, and the good-natured and infirm old man, Gregory XV., ascended the papal chair, Galileo sustained a blow which was most disastrous to him. This was the death, on 28th February, 1621, of his kind protector and patron, Cosmo II. The protection of an energetic prince who sincerely respected him, which he had hitherto enjoyed, was replaced by the uncertain favour of a feminine government, as the widowed Grand Duchess, whose tendencies were thoroughly Romish, assumed the regency for Ferdinand II., who was still in his minority.

Under these circumstances Galileo was but little inclined to bring out his reply; and perhaps the time when they were founding the Propaganda at Rome, and enrolling Loyola and Xavier among the saints, did not seem very opportune. From the new Pope personally there was nothing to fear. The phlegmatic little man, who was so bowed down by age and sickness that those about him often feared to lay complicated business matters before him, lest he should entirely break down, was certainly not likely to inspire awe; besides, Gregory had expressed himself to Ciampoli very favourably of Galileo.^[11] But the Pope's infirmities made it all the more necessary to proceed with caution; for they allowed the Romish administration to exercise full sway. And the man who guided it with almost sovereign authority was the Pope's nephew, Cardinal Lodovico Lodovisi, a former pupil and therefore zealous friend of the Jesuits.

Nevertheless Galileo's adherents, and especially his clerical friends at Rome, considered it absolutely necessary to publish his reply as soon as possible, with the precautions before mentioned, because his opponents construed his silence into a triumph for Grassi and the Aristotelian school.^[12] Prince Cesi, Mgrs. Cesarini and Ciampoli—the latter of whom meanwhile had become Secretary of the Papal Briefs to Gregory XV., a post which he also held under his successor, Urban VIII., until he fell into disgrace about Galileo—urged him repeatedly to finish his reply.^[13]

Francesco Stelluti, a member of the Accadémia dei Lincei, a learned friend of Galileo's, did indeed at this time (June, 1622) bring out a work against "Lothario Sarsi," but he only defended Guiducci, and studiously avoided touching on the reproaches cast on Galileo, in order not to anticipate him.^[14]

At length, in October of the same year, Galileo sent the MS. of his celebrated work, "Il Saggiatore" (The Assayer), to Mgr. Cesarini, at Rome.^[15] For five months it passed from hand to hand among the members of the Accadémia dei Lincei, who carefully criticised it, and with Galileo's consent, altered the passages which might possibly have been taken advantage of by his enemies to renew their intrigues against him. The Jesuits meanwhile had got wind of the completion of the reply, and did their utmost to get hold of one of the numerous copies of the MS.; but Cesarini, Cesi, Ciampoli, and the other "Lynxes," took good care of them, well knowing that if the Jesuits once made acquaintance with this crushing reply, they would use every endeavour to prevent its receiving the imprimatur.^[16] This was granted on 2nd February, 1623, by the supreme authorities of the censorship, not only without hesitation, but they spoke of the work in very favourable and flattering terms. The opinion— which was drawn up by Father Nicolo Riccardi, a former pupil of Galileo's, who will often be mentioned in the sequel, then examiner, and afterwards even Magister Sacrii Palatii—was as follows:—

 

"By command of the Master of the Palace I have read the work, 'Il Saggiatore,' and not only have I detected nothing in it which is contrary to good morals, or deviates from the divine truth of our religion, but I have found in it such beautiful and manifold observations on natural philosophy, that I think our age will not have to boast merely of having been the inheritor of the labours of earlier philosophers, but also of having been the discoverer of many secrets of nature which they were not able to penetrate, thanks to the subtle and solid researches of the author, whose contemporary I think myself happy to be, for now the gold of truth is no longer weighed wholesale and with the steelyard, but with the delicate scales used for gold.^[17]

 

The commencement of the printing was again delayed till the beginning of May,^[18] and then proceeded but slowly, for it was not until 27th May that Ciampoli sent the first two sheets of the "Saggiatore" to the author, in order to prove to him the falseness of a report which had meanwhile gained currency, that the printing of the work had been prohibited.^[19]

An event then took place which seemed likely to produce a great change in Galileo's relations with Rome; indeed in the whole attitude of ecclesiastical authority towards the free progress of science. At all events, as we shall see, Galileo flattered himself with this hope, and not without some justification. On 8th July, 1623, Gregory XV. succumbed to age and infirmity in the second year of his pontificate. The man who at the age of fifty-five was now elevated to the papacy, not only did not in the least resemble his immediate predecessors, but his tendencies were in striking contrast to theirs. He was previously Cardinal Maffeo Barberini, and now ascended the papal throne as Urban VIII.

1. See letter from Cesi to Galileo. (Op. viii. pp. 389, 390.)
2. Op. ii. pp. 387-406.
3. Op. vi. pp. 278-281.
4. Op. xv. (Viviani), p. 350.
5. Nelli, vol. i. p. 432.
6. Op. iv. p. 16. This appears also from a letter from Galileo of 19th June, 1619, to Cardinal Maffeo Barberini, afterwards Pope Urban VIII., accompanying the treatise. (See this letter in "Pieralisi," pp. 63, 64; and "Guitoloni et Gal. Galilei," Livorno, 1872, vol. i. p. 263.)
7. "Libra Astronomica ac Philosophica qua Galilæi Galilæi opiniones de cometis a Mario Guiduccio in Florentina Academia expositæ, atque in lucem nuper editæ examinatur a Lothario Sarsi Sigensano." (Op. iv. pp. 63-121.)
8. See the letter of Mgr. Ciampoli of 6th December, 1619, to Galileo. (Op. viii. pp. 430, 431.)
9. Compare the letters of Stelluti (27th January, 1620) to Prince Cesi, 4th March and 18th May, 1620; and from Mgr. Ciampoli, 18th May, 1620, to Galileo. (Op. viii. pp. 436-439, and 441-443.)
10. See his letter of 12th and 17th July, 1620, to Galileo. (Op. viii. p. 447; Wolynski, "Lettere inedite," etc., p. 59.)
11. See Ciampoli's letter to Galileo, 27th May, 1623. (Op. ix. p. 30.)
12. Compare Cesarini's letters to Galileo of 23rd June, 1621, and 7th May, 1622. (Op. ix. pp. 5 and 18.)
13. See his letters to Galileo in 1621 and 1622. (Op. ix. pp. 11–14 and 16–18; and Wolynski, "Lettere," etc., p. 65.)
14. "Scandaglio della Libra Astronomica e Filosofica di Lothario Sarsi nella controversia delle Comete, e particolarmente delle tre ultimamente vedute l'anno 1618, di Giovanni Battista Stelluti da Fabriano dottor di Legge."
15. "Il Saggiatore, nel quale con bilancia esquisita e quista si ponderano le cose contenute nella Libra Astronomica e Filosofica di Lothario Sarsi Sigensano."
16. See Cesarini's letter to Galileo, 12th January, 1623. (Op. ix. pp. 22–24.)
17. Op. ix. p. 26.
18. See Ciampoli to Galileo, 6th May, 1623. (Wolynski, "Lettere," etc., p. 68.)
19. See Ciampoli's Letter to Galileo, 27th May, 1623. (Op. ix. p. 30.)