The Believing Brain - Michael Shermer [155]
This is, in fact, what happened to the legend that Galileo was tortured and jailed for his beliefs. Because the church did not release the documents detailing precisely what was done with Galileo, but did release statements that said Galileo would be subject to “rigorous examination” (which at the time everyone knew meant torture), people naturally assumed that Galileo was tortured and jailed for his beliefs.12 In reality, because of Galileo’s fame and the respect he held among so many prominent people in power, and especially because of his recantation, the court granted him a “salutary penance” performed “for the spiritual benefit of former heretics who had returned to the faith,” and he was thereafter confined to what amounted to a very comfortable house arrest. He could leave the confines of the building and even go to visit his daughter in a nearby convent. Nevertheless, Dialogue was banned and Galileo was prohibited from ever again teaching the Copernican system.13 Remarkably, Galileo’s Dialogue remained on the Catholic Church’s Index of Prohibited Books until 1835, and it was not until 1992 that Pope John Paul II exonerated Galileo with an official apologia that reveals how belief systems can and do change once they are decoupled from unchanging dogmas, even if it takes three and a half centuries to do so:
Thanks to his intuition as a brilliant physicist and by relying on different arguments, Galileo, who practically invented the experimental method, understood why only the sun could function as the centre of the world, as it was then known, that is to say, as a planetary system. The error of the theologians of the time, when they maintained the centrality of the Earth, was to think that our understanding of the physical world’s structure was, in some way, imposed by the literal sense of Sacred Scripture. Let us recall the celebrated saying attributed to Baronius, “Spiritui Sancto mentem fuisse nos docere quomodo ad coelum eatur, non quomodo coelum gradiatur.” [“It was the Holy Spirit’s intent to teach us how one goes to heaven, not how the heavens go.”]14
Why did redemption take so long? Galileo’s own words in a 1615 letter to the grand duchess dowager Christina, with whom he had been corresponding about his heretical ideas in support of Copernicus, provide some insight: “Methinks that in the discussion of natural problems we ought not to begin at the authority of places of Scripture; but at sensible experiments and necessary demonstrations.”15
Methinks Galileo knew perfectly well what he was doing—and what the consequences would be—by prodding these old Aristotelians into looking through his tube.
The Battle of the Books
The allegiance to the authority of both scripture and Aristotle made it very difficult for the scholars of Galileo’s time to accept his observations—and especially the inductions he drew from them—as true. And he knew it. This is why Galileo commented in his book Bodies in Water, with epigrammatic poignancy, “The authority of Archimedes was of no more importance than that of Aristotle; Archimedes was right because his conclusions agreed with experiment.”16 Four centuries later, the physicist Richard Feynman echoed Galileo’s principle in his observation about determining if your theory is right or wrong: “If it disagrees with experiment, it is wrong. In that simple statement is the key to science. It doesn’t make any difference how beautiful your guess is, how smart you are, who made the guess, or what his name is. If it disagrees with experiment, it’s wrong. That’s all there is to it.”17
What Galileo reflected in his observations was one end of a spectrum that grew out of the Scientific Revolution that had begun more than a century before and culminated in a battle of the books: the book of authority versus the book of nature. Andreas Vesalius’s dissections of the human body in his 1543 On the Fabric of the Human