In consequence of this denunciation the Holy Office felt itself called upon at once to institute a secret inquiry about the astronomer. As Lorini had only been able to show a copy of Galileo’s letter to Castelli in confirmation of his accusations, it appeared to the Inquisition to be of great importance to obtain possession of the original, written and signed by Galileo. To attain this end the worthy gentlemen acted on the principle that “the end sanctifies the means.” Cardinal Mellini, under date of 26th February, ordered the secretary of the Holy Congregation to write to the Archbishop of Pisa and the Inquisitor there, that they were to procure that document “in a skilful manner.” On the very next day the order was despatched.[99]
It happened that a few days later Castelli, who had returned from a short stay at Florence to Pisa, paid a visit to the archbishop, Francesco Bonciani. He seized the opportunity of executing his commission. With this end in view he began by adjuring the father, who was quite taken aback by such an exhortation, to give up certain extravagant opinions, particularly that of the revolution of the earth, adding that it would be to his salvation, while to hold them would be to his ruin, for those opinions (to say nothing of their folly) were dangerous, repulsive, and mischievous, for they were directly opposed to Holy Scripture. The philosophical arguments with which the archbishop tried to convert Castelli to orthodox astronomy rose to a climax in the profound remark that as all things (creatura) had been created for the use and benefit of man, it was obvious that the earth could not move like a star.[100] After giving this affectionate counsel to Castelli he offered the same for Galileo, and declared himself ready to demonstrate to all the world the folly of that opinion. But, in order to do it successfully, he must first acquaint himself thoroughly with Galileo’s arguments; and, therefore (and now comes the gist of the matter) he urgently begs Castelli to let him see Galileo’s apologetic letter.
Fortunately it was no longer in Castelli’s possession, for he had returned it to the author. For not only did he not in the least perceive the trap that was laid for him, but was so innocent as to inform Galileo of the request and warmly to second it.[101] But Galileo had suspicions, and delayed to reply. The archbishop was annoyed, and reported in two letters to Rome, of 8th and 28th of March,[102] that Castelli was convinced that he only wanted to see the letter out of curiosity, and as the common friend of both had written to Galileo; still Galileo had not sent it. Bonciani therefore asks “whether he shall be more open with Castelli?” But this time cunning did not attain its end; at the repeated urgency of Castelli,[103] Galileo at last sent him a mere copy without signature, and with the express reservation that he was not to let it go out of his hands. From a letter of Castelli’s[104] to Galileo we learn that in obedience to this injunction Castelli read it to the archbishop in presence of several canons, and that he diplomatically concealed his annoyance at the failure of his intrigue, and put a good face on it, for Castelli adds with great satisfaction that the archbishop had highly praised Galileo’s demonstrations, and lauded to the ecclesiastics present the modesty and reverence for Holy Scripture therein displayed.
So Cardinal Mellini had to content himself with a copy of Galileo’s criminated epistle, to lay before the consultor of the Holy Office for his opinion. He pronounced that some words and phrases occurred in the document that were unsuitable; but, although at first sight they looked ill, they were capable of being taken in a good sense, and were not of that nature that they could be said to deviate from Catholic doctrine.[105]
Meanwhile a papal mandate had been issued, under date of 19th March, to summon Caccini as a witness, as being specially well informed about Galileo’s errors.[106] He appeared before the holy tribunal the very next day, and eloquently poured forth his accusations; but, although upon oath, he did not adhere very strictly to truth. For not only did he denounce the opinion of Copernicus as quasi heretical, being opposed to all scholastic theology and to the customary interpretation of many passages of Scripture, and assert that these doctrines were to be found both in the letter to Castelli and in the purely scientific treatise on the solar spots, but added the far more serious charge that he had heard that Galileo maintained the three following propositions: “God is not a self existent being, but an accident; God is sentient because the Divine sentiments reside in Him; the miracles said to be performed by the saints are not real miracles.” He further says that Galileo is at any rate “suspicious in religious matters,” because he belongs to “a certain Accadémia dei Lincei,” and corresponds with the godless Fra Paolo Sarpi at Venice, and with many dissolute Germans. More absurd deductions from real facts can hardly be conceived. To make a hotbed of heresy out of an academy founded by Prince Cesi, a man of known piety, and to place Galileo’s religion in doubt on account of his scientific correspondence with magnates of science like Sarpi, Welser, Kepler, etc., was almost like madness.[107]
In confirmation of his damaging statements Caccini appealed to the testimony of a Dominican, Ferdinand Ximenes, and a young nobleman, Attavanti. Both of them were afterwards called in November of the same year. It then came out that Caccini was not only an eavesdropper but a bad listener. Attavanti, who moreover was far more a disciple of the Dominicans than of Galileo, had once had a discussion with Ximenes, in their convent of Santa Maria Novella, about the proposition concerning the nature of the Godhead, but it originated entirely in scholasticism and had nothing to do with Galileo. Caccini, listening behind a partition, caught something of the conversation; and, thinking that Attavanti was a well instructed follower of Galileo, and was merely repeating what he had taught him, explained the fragments of the disputation in his own fashion, and formed them into these stupid accusations. It also appeared from the evidence of Ximenes and Attavanti that neither of them knew of anything suspicious about Galileo, except that he propounded the doctrine of the double motion of the earth.[108]
After the favourable testimony of Ximenes and Attavanti the evidence of Caccini was only so far of importance that it gave rise to an inquiry into the “History and Explanation of the Solar Spots.”[109] This, and the oft discussed letter to Father Castelli then, were the grounds upon which Galileo’s enemies based the accusation of philosophical and theological error.