History in Five: What made you want to write this book? 

Mario Livio: Galileo Galilei has always fascinated me. To this very day, I do not quite understand how he managed to reach this incredible insight that the universe is “written in the language of mathematics,” at a time when none of the mathematical expressions we call today laws of nature existed. He was not only one of the founders of modern science, but also a larger-than-life hero of our intellectual history and an icon of the fight for scientific freedom. The attempts we have been witnessing today to deny the reality of climate change, made me realize that this book is needed now. Furthermore, the initial tendency in some circles to minimize the dangers of the coronavirus only enhanced my conviction that Galileo’s story is currently more important than ever. 

H5: There are so many biographies of Galileo. What makes this one different? 

ML: I have three main points here. First, very few of the biographies were written by research astronomers or astrophysicists. I believe that as an active astrophysicist I have brought a fresh perspective to the scientific discoveries. Secondly, I demonstrated why Galileo’s story is so relevant as a cautionary tale for today’s culture of dismissal of scientific expertise. Finally, it was my goal to write a less dense, shorter biography, that would be more accessible to the general public, all without sacrificing accuracy. 

H5: How did your scientific background help you in writing this book? 

ML: Galileo is legitimately regarded as the father of modern astronomy and astrophysics. I have attempted to place his discoveries in the context of today’s knowledge and ideas. In particular, for every one of his discoveries or theories, I explained our current thinking, while emphasizing not only Galileo’s successes but also where he was wrong. 

H5: What was the most surprising thing you learned about Galileo’s life and work in your research? 

ML: I was amazed to discover to what extent his story shines light on a few of the problems we are facing in the twenty first century. These range from anti-science attitudes expressed by officials at the highest positions, through the continuing debate concerning the teaching of creationist ideas side by side with Darwinian evolution, to the perception of a widening gap between the humanities and the sciences. 

H5: Did you have to undertake any unusual research to write the book, or visit any particular collections? 

ML: Absolutely. I spent time as a visitor at the Galileo Museum in Florence, I consulted with four of the greatest Galileo scholars living today, and I used materials from the Special Collections of several universities. In addition, I conducted an extensive original research to determine the origin of Galileo’s most famous motto: “And Yet It Moves.” I am publishing the results of that research as a separate, original article. 

H5: You use the examples of climate change and objections to vaccines and to Darwinian evolution throughout the book to show how even today there are many who doubt science. How are these beliefs equivalent to the Church’s in Galileo’s day? 

ML: Following Galileo’s observations no one could argue anymore that what one saw through the telescope was not a faithful representation of reality. The only argument remaining to those refusing to accept the inevitable conclusion that the Earth is revolving around the Sun, was to reject the interpretation of the results on the basis of religious or political ideology. This is disturbingly similar to the denial of climate change or of the theory of evolution by means of natural selection. 

H5: What should we all take to heart from Galileo’s story? 

ML: The answer is simple: Believe in science! It is generally not wise to bet against the judgement of science. In a case such as climate change, or a pandemic, when the fate of life on our planet is at stake, it is absolutely insane. 

H5: Your book is coming out in a time when the world is facing a pandemic—are there any lessons from your book that you think apply to the COVID-19 -19 outbreak as well, and how it has been handled by governments and authorities around the world? 

ML: I repeat: Believe in science! In places such as South Korea, where the data were taken seriously from the start, and the advice of the scientists was followed immediately, and to the letter, they had success in slowing down the epidemic. They initiated a well-organized testing program, combined with genuine efforts to isolate infected people and trace and quarantine those they had been in contact with. 

H5: Is there anything else you’d like readers to think about? 

ML: Yes. First, we should realize that as long as the conclusions of science concerning physical reality are accepted, with no intervention of religious beliefs and no denouncing of provable facts, no conflict between the two realms can exist. Second, Galileo was a true “Renaissance person,” to him the sciences and the humanities were both indispensable parts of one human culture. Third, intellectual freedom is invaluable. This is the right of everyone to receive information from all points of view without restriction. It encompasses the freedom to hold, receive and disseminate ideas. Putting Galileo on trial by the Inquisition was wrong not just because he was right about the science. It would have been wrong even if his theories were completely false!