The Roman Inquisition. Thomas F. Mayer

that he did not want his letter taken as a “judicial deposition” against Galileo and instead as “a loving piece of news (avviso).”²³ In choosing this form of words, it seems likely that Lorini had in the back of his mind the contrast between a legal proceeding and the much milder “charitable admonition.”²⁴ The Congregation of the Index, unlike the Inquisition, had no judicial powers; all it could do was prohibit books, not punish their authors or those who read them. Given Sfondrato’s annoyance with the toothless Index, Lorini virtually goaded him into pursuing the first option. Lorini pushed Sfondrato further in the direction of a legal remedy by providing written evidence, the enclosure in his letter, which he had also shown Caccini. This was a copy of Galileo’s letter to his favorite pupil, Benedetto Castelli. Lorini set the letter in a false context by claiming it had been written in reaction to Caccini’s sermon when in fact it dated from exactly a year earlier. This was a stupid thing to do, since the copy had the correct date of 21 December 1613.

      Galileo’s Letter to Castelli

      Lorini had good reason to think the “Letter” might cause Galileo trouble. In it Galileo offered his most extended discussion of the relations between Copernicus’s ideas and scripture and, unlike in the case of his correspondence with Piero Dini, did so in a more or less public way, even if not in the medium of print.

      The “Letter” arose out of a debate in the grand duke’s presence between Castelli, the grand duchess mother, the grand duke’s wife, and a few other members of their court. Reasonably subtly, Galileo sent Castelli more arguments he could (or should) have used in reply to objections the two women had made “especially about the verse in Joshua [10.12–13] proposed against the mobility of the earth and the stability of the Sun.”²⁵ His first point concerned the inerrancy of scripture. While agreeing with Castelli that scripture could never be wrong, Galileo maintained that “nonetheless its interpreters and expositors can err in various ways, among which would be a most serious and frequent one when they would want always to stop at the pure literal sense.” Galileo may have thought this a simple point, but, as we have seen, the literal sense was precisely where Galileo’s opponents thought they stopped, no matter how quickly they moved to metaphorical interpretation. Many things in scripture seemed not only contradictory but heretical and blasphemous when read at that level. “Therefore, since in the scripture there are many false propositions as far as the plain sense of the words, but which have been expressed in that manner in order to accommodate the incapacity of the many common people, thus for those few who deserve to be separated from the dull common people it is necessary that wise expositors of scripture extrapolate the true senses and add the particular reasons why such meanings are expressed in such words.”²⁶ Galileo drew the conclusion that “Since, therefore, sacred scripture in many places is not only susceptible of, but necessarily in need of expositions varying from the apparent sense of the words, it seems to me that in discussions of natural [philosophy] it ought to be reserved to the last place.” From its interpreters to the text of scripture evidently seemed a short step to Galileo, but falsity in the first case connoted mere human error, whereas in the second it could only mean a breakdown in the communication of the divine word and, worse, dethronement of what his opponents regarded as the most direct form of that communication.

      Scripture had to give way to nature because there was only one truth, and nature, unlike scripture, “is inexorable and immutable and does not care at all that its hidden reasons and means of proceeding may be or may not be fit for men’s capacity.” Then Galileo introduced his famous two-pronged mode of discerning nature’s intent, “sensory experience” (esperienza, which also means “experiment” in Italian) and “necessary [logical] demonstrations.”²⁷ The rigor of this approach combined with nature’s law-governed behavior meant that any passages in scripture that appeared to contradict a natural effect should never be allowed to raise questions about it. Galileo pushed the point into increasingly dangerous territory, drawing another corollary about scripture: “Indeed, if only for this reason, to accommodate the incapacity of the people, scripture has not abstained from perverting some of its most principal dogmas, attributing to God Himself conditions very far from and contrary to His essence.” Thus “wise expositors” had to find meaning in scripture that agreed with “those natural [philosophical] conclusions of which first the plain sense or general, indeed necessary, demonstrations have made us certain and sure.” First nature, then the Bible. Therefore, no interpreter should be forced to maintain a proposition drawn from the Bible that “those natural conclusions” do not support.

      Then Galileo drew a distinction between kinds of biblical content. Articles about the faith had such “firmness” that there was no danger of contradicting them; therefore nothing should be added to them “unnecessarily.” Scripture existed solely to persuade humans “that those articles and propositions that, being necessary for their salvation and surpassing any human discourse, could not have made themselves believable by any other science nor any other means than by the mouth of the Holy Spirit itself.” Interpreters of the Bible could not be trusted, since one never knew whether they spoke by divine inspiration. Contrariwise, Galileo did not think God meant to deny humans the use of their senses in the investigation of natural phenomena, especially since the Bible contained almost nothing about them, “such as precisely is astronomy” (52). Repeating his claim that two truths could not contradict one another, Galileo concluded that those who had the right to investigate nature—meaning philosophers—should not be forced by threats to concede to those who could not avoid presenting sophistical and false arguments (53).

      In order to demonstrate his point, Galileo turned to Joshua. Like his “adversary,” Galileo proposed to begin from the text’s literal sense. But he drew the opposite conclusion, “that this verse shows clearly the falsity and impossibility of the Aristotelian and Ptolemaic world system, and by contrast fits the Copernican very well.” True to his own method described earlier, Galileo immediately ignored the Bible and instead carefully constructed an argument grounded in sensory experience and necessary demonstrations. How many movements does the sun have, he asked? Two, annual and daily. Of these, only the first “belonged” to it; the Primum Mobile transmitted the second to it, which produced day and night. Galileo concluded rhetorically that prolonging a day meant stopping the Primum Mobile, not the sun. Indeed, stopping the sun would shorten the day. This was a clever sally against Ptolemaic and Aristotelian astronomers, unhorsing them, as Galileo might have said, with one of their own central concepts. Either Ptolemy was wrong about the Primum Mobile, or the literal sense of the scripture was in saying sun instead of Primum Mobile. Nor could God have stopped the sun alone, since that would have caused unnecessary disruption of “the entire course of nature,” that law-governed behavior on which Galileo had earlier insisted.

      Instead Galileo offered in a few lines a simple Copernican solution. Since the sun gave movement to the earth, to stop the earth one had only to stop the sun, just as the Bible said (55). And that was that.

      The matter was not so simple to Galileo’s opponents. Although we have no direct response to the “Letter” from any of them, we can infer from the underlining in the copy in Galileo’s dossier that Galileo’s science, including his alternative explanation of the text of Joshua, interested them not at all. Instead, his handling of scripture drew all their attention.

      And quickly. Not ten days after Lorini’s letter, Galileo knew that a copy of the “Letter to Castelli” was circulating among his enemies, apparently including in Rome, who found “many heresies” in it and used it to “open a new field to injure me.”²⁸ Writing to Dini, whom he thought to be one of his closest allies in Rome, Galileo also casually, perhaps too casually, suggested that “whoever transcribed it [the ‘Letter to Castelli’]” had “inadvertently changed some words,” which, together with “a little disposition to censures, could make things appear much different from my intention.” He had also heard that Caccini had gone to Rome “to make some other attempt” against him. (Whatever he knew about Lorini’s actions, chronology makes it seem certain that Caccini’s departure triggered Galileo’s letter. The two events came at most two days apart.) As a prophylactic, Galileo enclosed a copy “in the right manner that I have written it.” He hoped Dini would show the correct version to the Jesuit mathematician Christoph Grienberger,