Wilding discovered that the manuscript itself solves one mystery: why did this copy survive the Great Fire when its siblings were burned? The book is incomplete. It is missing a chunk in the middle and ends abruptly, mid-sentence, in the middle of the final of five books. And tellingly, some of the pages are full of proofreader's marks. For Wilding, these clues point to one conclusion: The copy that exists today was an incomplete version taken home by a proofreader, away from the fire's epicenter, and spared from the brunt of the disaster.
The text's curious state—unfinished and annotated—provided Wilding with insights into the overlapping worlds inhabited by Galileo, Salusbury and the publishing industry. Like many works of the time, it has its share of inconsistencies, partly because Galileo's apprentice Viviani controlled the firsthand evidence and Salusbury had to rely on secondary sources.
"Quite a lot of it is wrong," Wilding says. "But that makes it even more interesting for historians because you have to explain the mistakes as well as the facts." For example, Salusbury parrots rumors of the time that Galileo was an illegitimate child, and that his wife tore up many of his scientific papers at the request of a nefarious priest. Modern scholars know both claims are false; in fact, Galileo never even married. But these inaccuracies point to the rampant anti-Catholic, misogynistic sentiments of many in the Italian scientific circle at the time, Wilding says. "For them, it was, 'Bad priest! Stupid women!'"
But the most striking finding might not be an error at all. Salusbury presents a novel motivation for Galileo's infamous trial, Wilding says. If people know anything about Galileo's trial, it's usually that the church disapproved of his advocacy of the idea that the earth orbits the sun. In many people's minds, Galileo is a kind of martyr figure for science and a cautionary tale against allowing religious authority to trump scientific inquiry.
"There's been a very long discussion about the trial—what happened, who won—and to some extent that's still going on today," Wilding says. "The usual interpretation is that this was the great rift between science and religion. You've got this arrogant scientist up against a dogmatic church, and in that head-ramming, the pope's going to win."
Not that modern scholars give much credence to the traditional science-vs.-religion interpretation of the trial. Most Galilean researchers today agree that politics played a much bigger role than religious closed-mindedness, but there is spirited disagreement about the specifics. Some think the pope was angry at being parodied by Galileo's character Simplicius in Dialogue Concerning the Two Chief World Systems. Other scholars have suggested that church leaders felt Galileo had tricked them into granting him a license to write the book by not revealing its Copernican leanings. But "Salusbury's explanation is kind of refreshingly new," Wilding says.
It goes like this: In the middle of the Thirty Years' War between the Holy Roman Empire and almost every major power in Europe, tensions were high between Tuscany and Rome. The Tuscan Duke of Medici had refused to aid Rome in its war efforts against France. Pope Urban VIII decided to punish the Duke by arresting the Duke's personal friend, Galileo.
Whatever its motivation, the Roman court found Galileo guilty of heresy and placed him under house arrest. He spent the first five years of his sentence in a small house near Florence, where he continued to publish work on the science of motion, and the next—and last—four years of his life confined to another home in Florence closer to his doctors.
"No other historian in the 350 years after the trial has ever proposed the theory" that the Pope persecuted Galileo to punish the Duke of Medici, Wilding says. Written only 20 years after Galileo's death, the newfound biography represents one of the earliest explanations for the trial ever recorded. "To me, it feels right," Wilding says. The idea "might provide some closure to a still-festering wound."
But Wilding admits that Salusbury himself could be projecting his own interpretations on the event. That's the view Galilean historian Paula Findlen, at Stanford University, takes. To her, the accuracy of Salusbury's claims is less interesting than the fact that Salusbury is claiming them at all. "It's interesting to see how people at that time, from outside Italy, are starting to reconstruct Galileo's life," Findlen says. It shows that people immediately recognized the importance of Galileo, of his works and of his trial. And not only did they grasp the significance, they also suspected that politics was at the root of the trial, even then. "Even if you disagree with Salusbury's interpretation, it reinforces the idea that people knew there was something deeply political about the whole thing."