The Investigation and the Trial

(The picture is from - The Universe of Galileo and Newton, By Bixby, William, 1966, p.77)

In order to understand the investigation process and Galilei's trail we recommend to look at - Lexicon Galileo's trial.

THE TRIAL - Discussion Forum

In the summer of 1632, a short time after the publication of the Dialogue Concerning the Two Chief World Systems, many complaints against the book were lodged in Rome. Following these complaints, Pope Urban XIII ordered that printing of the book be stopped and an investigation begun. Galileo was not an ordinary man, and the investigation of his book therefore received special attention. As the most renowned scientist of his age, he had many patrons in the higher Episcopal and secular echelons. Urban himself had bestowed on him the title of "a favorite son of the Pope." The Pope nominated a special committee of cardinals to determine if the charges against Galileo merited an investigation by the Inquisition. These committees were very rarely appointed (perhaps once in decades), and dealt with particularly sensitive issues.

The special committee convened five times during the month of September and found three central problems in the book:

  1. Galileo did not obey the instructions of the Church censor. The spirit of the censor's instructions was not maintained since the introduction was added (see "Publication of the Dialogue") in a different typeface, and the final conclusion was not handled properly. The claims presented in the introduction and the epilogue were detached from the body of the book, which did not present the motion of the earth as a mere hypothesis.
  2. In his book, Galileo defends the Copernican theory as a real theory. This is evident by a number of examples such as his reference to the motion of the earth as real rather than hypothetical, and his claim that one cannot determine if the earth moves or not, despite the fact that it is known (from Scripture and the interpretation of the Church fathers) that it does not move.
  3. The most severe accusation was based on an unsigned document found in the Church, according to which Galileo had been personally forbidden not only to uphold and defend the heliocentric theory, but even to teach it, which he clearly does in the Dialogue.
Following the report of the special committee, the Pope transferred the investigation of the affair into the hands of the Inquisition. At this stage, the Tuscan Duchy attempted to intervene and bring the affair to a close, through diplomatic contacts with the Church. Galileo had been the Tuscan court philosopher for more than twenty years, and was the protege of the Grand Duke of Medici, to whom he had dedicated the Dialogue. Moves against Galileo were, in effect, moves against the Duchy. Throughout the autumn of 1623, the possibility of conducting the trial in Florence instead of Rome was discussed, yet despite the Tuscan efforts and the medical opinion regarding the deteriorating health of the 69 year-old Galileo, the Church insisted on Galileo's coming to Rome. The Pope, a past patron of Galileo, took his activities as a personal affront and refused to make things easier for him. In January 1633, Galileo left Florence and arrived in Rome two weeks later, where he found lodging at the Tuscan ambassador's home rather than the Inquisition house of detention. He was, however, placed under house arrest. On April 12, he was taken for his first official interrogation.

During this interrogation Galileo responded to the most serious claim leveled against him. Against the unsigned document which claimed that Cardinal Bellarmine forbade him to teach the Copernican theory, he presented Bellarmine's signed certificate. In this document, Bellarmine certifies that Galileo knows about the general prohibition, and does not mention the prohibition on teaching the theory. Against the other accusations, he continued to claim that in the Dialogue he did not wish to uphold or defend the heliocentric theory. Galileo's response surprised the inquisitors, who were not acquainted with the Bellarmine certificate. After the initial investigation, there was another break in the proceedings. The Inquisition conducted negotiations out-of-court, similar to our present day "plea bargain." Galileo was accused in the slighter transgression, that of defending the Copernican theory contrary to the explicit Church verdict.

The Dialogue was given to three different consultants, who were charged with examining if it subscribed to or defended the theory that the earth moves. All three claimed that the book defends the theory and is also close to subscribing to it (an opinion accepted by most historians also today). Equipped with these expert opinions, the representatives of the Inquisition now turned to Galileo, demanding that he admit this guilt. A number of days later, on April 30, Galileo reappeared before his inquisitors and admitted his guilt. He declared that after three years, he had once again read his own book and had been surprised to find that it defended the theory stating that the earth moves, although this had not been his intention. Galileo explained that he had defended the theory because of his arrogance and his attempt to write the Dialogue in the most convincing way possible, by upholding the erroneous claims. Thus, out of his literary arrogance and his love for his own creation, he had sinned in defending the Copernican theory, and he now repented and asked forgiveness.

After this declaration, Galileo was taken for an additional interrogation, during which he was asked about his intentions when writing the Dialogue, and whether he upheld the theory (banned in 1616) according to which the sun is stationary and the earth revolves around it. Galileo responded to these questions by saying that he had not subscribed to the Copernican theory and his intentions were pure. The decision in this trial was so sensitive that it required the Pope's authorization. Urban XIII suspected Galileo's motives and demanded that he be interrogated again, this time under the threat of torture - an accepted Inquisition practice. Galileo repeated his version in this interrogation. In addition, the Pope also demanded that Galileo publicly recant the heliocentric theory and that the Dialogue be banned - even after it was made clear that Galileo's motives were pure (from an Episcopal point of view), and he had not attempted to defend the Copernican theory.

The verdict was given on June 21, and was surprising in its severity. Despite the pronouncement of reduced guilt as regards his defense of the Copernican theory, the tribunal found Galileo guilty of " Suspected heresy," a term which constituted an actual offense. Galileo was charged with this on account of: "maintaining and believing an erroneous doctrine which contradicts Scripture: that the sun is the center of the world and does not move from east to west, and that the earth moves and is not the center of the world, and for claiming that this theory may be possible, and for continuing to subscribe to it after it has been declared and defined as conflicting with Scripture". Galileo was also accused of misleading the censors in that he did not tell them of the Episcopal consultations on Copernicanism in which he was involved in 1615-16. The sentence was also harsh: Galileo was sentenced to an unlimited period of imprisonment and to publicly recant this doctrine. Moreover, publication of the Dialogue was prohibited. Only seven out of the ten judges signed the verdict. Galileo was not imprisoned in the cellars of the Inquisition. He was taken to the home of the Tuscan ambassador, and six months later he returned home, where he remained until his death.

Why so harsh a verdict and sentence? Why was the trial so important for the Pope? Why did the Church so strongly object to the heliocentric world view? These are some of the questions still debated among historians, clergymen and others who study the trial.

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