This might seem strange because Sagan was an early promoter of the theory that man-made emissions of carbon dioxide are going to fry the globe. But it’s not so strange when you consider the larger message that made Sagan famous.
As with many people my age, Sagan’s 1980 series “Cosmos,” which aired on public television when I was eleven years old, was my introduction to science, and it changed my life. “Cosmos” shared the latest developments in the sciences of evolution, astronomy, and astrophysics, but its real heart was Sagan’s overview of the history of science and the distinctive ethos behind the scientific method. Sagan returned again and again to one central theme: that the first rule of science is to follow the evidence wherever it leads, regardless of one’s wishes or preconceptions. He spoke eloquently about the Ancient Greek Pythagoreans and their attempt to suppress the facts about “irrational numbers” that didn’t fit their theory. And he spoke admiringly about the 17th-century astronomer Johannes Kepler, who started out pursuing a theory in which the planets move in circular orbits reflecting the ratios of the perfect Pythagorean solids—and ended up being driven by the evidence to reject this theory and discover completely new laws of planetary motion.
I didn’t end up becoming a scientist, but I absorbed Sagan’s basic lesson and have tried my best to adhere to it in my own field: follow the evidence wherever it leads.
Giant instruments are giving us a sea of data. Can science find its way without any big ideas at the helm?
Philip Ball writes: Whenever I visit scientists to discuss their research, there comes a moment when they say, with barely concealed pride: ‘Do you want a tour of the lab?’ It is invariably slightly touching — like Willy Wonka dying to show off his chocolate factory. I’m glad to accept, knowing what lies in store: shelves lined with bottles or reagents; gleaming, quartz-windowed cryogenic chambers; slabs of perforated steel holding lasers and lenses.
It’s rarely less than impressive. Even if the kit is off-the-shelf, it is wired into a makeshift salmagundi of wires, tubes, cladding, computer-controlled valves and rotors and components with more mysterious functions. Much of the gear, however, is likely to be homemade: custom-built for the research at hand. Whatever else it might accomplish, the typical modern lab set-up is a masterpiece of impromptu engineering — you’d need degrees in electronics and mechanics just to put it all together, never mind making sense of the graphs and numbers it produces. And like the best engineering, these set-ups tend to be kept out of sight. Headlines announcing ‘Scientists have found…’ rarely bother to tell you how the discoveries were made.
Would you care? The tools of science are so specialised that we accept them as a kind of occult machinery for producing knowledge. We figure that they must know how it all works. Likewise, histories of science focus on ideas rather than methods — for the most part, readers just want to know what the discoveries were. Even so, most historians these days recognise that the relationship between scientists and their instruments is an essential part of the story. It isn’t simply that the science is dependent on the devices; the devices actually determine what is known. You explore the things that you have the means to explore, planning your questions accordingly.