Galileo and Empirical Science

By Mark Thomas.

Around 1600, Galileo had a new idea for his culture. He decided to do something that now seems like common sense — to actually test the idea of what we now call gravity. He reasoned that two weights held together would fall at the same rate as one weight. Then he did experiments to test the idea. And, not surprisingly to us, it was true! This was the start of modern empirical science, and our collective understanding of the Universe hasn’t been the same since. “Empirical” is a word that I'll be using a lot. It refers to ideas that are capable of being verified or disproved by observation or experiment. Empirical evidence is not simply one type of evidence, but rather it is the only evidence that we can rely on, because it is reproducible. Empirical evidence is the basis for physical science.

Galileo also took the new invention of the telescope, refined it, and used it to look at the night sky. He was astounded. On the moon he could see mountains and valleys. It wasn’t just some strange heavenly object; it was probably made out of the same stuff as Earth. In 1609 Galileo looked at Jupiter, and discovered that it had four moons. If moons orbited Jupiter, then not everything orbited the Earth, as the Catholic Church taught at the time. Astronomy made more sense if the theories of Copernicus were true, and the Earth and planets orbited the sun. After writing a book about this, Galileo was called to Rome in 1633 by the Catholic Church’s Inquisition, and told to recant his heretical ideas.

This was no “simple request” by the Church. Just 33 years before, the Inquisition had executed Galileo’s friend Giordano Bruno. Have you heard of him? In 1600, the Christian authorities in Rome took him out of the dungeon he had been in for eight years, drove a nail through his tongue, tied him to a metal post, put wood and some of his books under his feet, and burned him to death. Bruno’s crime was writing ideas that the Catholic leaders didn’t like — there might be other worlds with other intelligent beings on them, Jesus didn’t possess god-like power, and souls can’t go to heaven. For these heretical ideas, the Catholic Church punished this brilliant thinker with a slow, agonizing death.

Galileo knew what he was up against. For the crime of heresy the Inquisition could put him in a dungeon, torture or even execute him — as it had done to Bruno. So, after a long trial, this proud 70-year-old man obediently got on his knees and recanted. But even after recanting, he was still sentenced to house arrest for the rest of his life. The Catholic Church officially condemned heliocentrism 31 years later, when Pope Alexander VII banned all books that affirmed the earth’s motion. But, even as powerful as the Church was, they could not hold back the tidal wave of scientific discovery, and the Church eventually lost its battle over our view of the Universe. It only took them over three hundred years to admit it. In 1992, after 12 years of deliberations, they grudgingly noted that Galileo had been right in supporting the theories of Copernicus. But no such admission has been made for Bruno; his writings are still on the Vatican’s list of forbidden texts, and Pope John Paul II refused to even apologize for the Catholic Church's torture killing of Bruno.

Could this sort of ‘oversight’ of Science by Religion happen again? Would we like to live in a world where the religious view of the Universe could not be challenged by Science? Do we really want to turn the clock back 400 years? It could get rather toasty for Free Thinkers...