People have grown more literate over time but I don’t know if they’ve really gotten any smarter. The New York Times reports that “people who question whether the Earth is round [are] running local Republican parties in Georgia and Minnesota and seeking public office in Alabama.”
By the fifth century B.C.E, the Greeks were confident enough that the Earth is an orb that they were making predictions about its circumference. For the math-challenged among you, that was two and a half millennia ago. Plato estimated the circumference as 64,412 kilometers (40,000 miles). The actual number is 40,096 kilometers (24,901 miles), so Plato was off by 60 percent.
One hundred and fifty years later, Archimedes gave an estimate of 48,309 kilometers (30,000 miles), which was only off by only 20 percent. In the third century B.C.E, Eratosthenes came very close to the correct answer with an estimate of 40,250 to 45,900 kilometers (25,000 to 28,500 miles). It’s fascinating to know how he arrived at this range.
He observed that the Sun was not casting a shadow down a well in the town of Syene, Egypt, which is now known as Aswan. From this he concluded that the Sun was directly overhead, which wasn’t quite true. He observed that on the same day of the year, a rod perpendicular to the ground in Alexandria, Egypt cast a shadow that was 7° 12′ from perpendicular.
He only needed a couple more inputs to make his calculation. First he figured out that 7° 12′ was one-fiftieth the size of a 360° circle. Then he needed to know how far Syene was from Alexandria. It’s unknown how he determined this but he found the result of 805 kilometers or 500 miles. This, too, was a little off. The correct distance would have yielded an angular measurement of 7° 30′ rather than 7° 12′. Another problem was that Alexandria is not due north of Syrene.
Despite these errors in his numbers and assumptions, his method was sound. He took the distance between the two cities (805 km) and multiplied by fifty. That gave him a circumference of 40,250. That’s astonishingly close to the modern estimate of 40,096.
What I find astonishing is that Eratosthenes understood that the problem actually could be solved in such a way. It’s not something that would occur to 99.99999 percent of all the human beings who lived before him, and nearly the same percentage of people who have lived after him. Yet, it’s surprisingly simple to solve once you accept and understand the principles involved. You need to know how to measure the angle off perpendicular for sunlight, and you need to know how to multiply. There’s no advance calculus or trigonometry involved.
I guess the first thing that needed to be understood is that there are 360° in a circle. The problem is really more a conceptual difficulty than anything else. And if begins with the theory that the Earth is round.
Of course, we know the Earth is round now because we’ve gone to outer space and taken pictures of it. That really ought to have settled all dispute, but apparently it hasn’t for the people running the Republican Party in Georgia, Minnesota and perhaps soon in Alabama.
Personally, I think the idea that the Earth is flat was ever widely believed, at least among the educated, is highly overrated. There was a big dispute over whether the Earth or the Sun is at the center of the Solar System which famously pitted the Catholic Church against Galileo, but that’s different from a belief that the Earth is round.
I guess the world appears flat unless you do a little investigating. Certainly, sitting at the beach and looking out at the sea, you can detect the curvature of the horizon. But most folks don’t live at the beach. Another clue is that everything else we can see in the sky, from the moon and the Sun to the planets and stars is clearly spherical. Why should the Earth be different?
In any case, I don’t believe most Ancient Greeks thought about or understood these things any better than most contemporary Americans. People have always been pretty simple on average and those who can think scientifically have always been a tiny percentage of the whole.
But the modern world we live in was made possible by that tiny percentage and the rest of us ought to be humble enough to defer to them on scientific questions like the shape and circumference of the Earth and whether and why it is warming. And we definitely shouldn’t vote for a party led by people who think the Earth is flat more than 2,000 years after Eratosthenes correctly guessed its actual size.
Wife and I went to Cincinnati last night and sat with about 2500 other science nerds and listened to a great presentation by Neil DeGrasse Tyson. While the official topic of the presentation was the search for other life in the universe, it was consistently sprinkled with references to the ongoing Republican war on science, the severe ramping up of anti-intellectualism as a political policy, and the danger of the risk to public health that is increasing every day as the GOP continues to dismantle decades of efforts to protect our food and water supplies, and pushes anti-vax messages straight from the office of the Secretary of Health and Human Services. Of course, as someone who comes from a science and engineering background, I felt a great kinship with everyone else there. There was little doubt that the audience probably did not contain a single MAGA person. If one was there, they certainly didn’t demonstrate any disagreements. At the end of the evening one could only draw the singular conclusion that scientists like Tyson are deeply concerned about the direction we are headed. As much as he would probably prefer to be apolitical, Tyson recognizes that this is really a fight for the continuing existence of humans on this planet. The planet doesn’t give two shits about our political fights. As Tyson posted in his presentation, “The Earth and the Universe are working to kill you”. And this is largely due to the actions that we ourselves are consciously and purposely taking.
Talking with my wife on the drive home, we were trying to imagine if any one of the many MAGA people we know was at that presentation, just how they would respond the rational and evidence driven presentation that we had heard. Our conclusion is that, if anything, they would have likely been more entrenched in their anti-science and anti-intellectual views. The drug that is cognitive dissonance is just too strong. The pull of their tribe is just too strong, And the fact that they now have a whole media universe, including their own “scientists”, which can feed their unfounded and delusional views during their every waking minute is just not something that is simply going to go away.
At the end of the night I took a bit of comfort that it appears those on the side of science seem to be girding for this fight, but the fact that those currently in charge in this country have what seems like an almost infinite amount of money and power to fight this battle. That seems like a mighty big hill to climb for those of us who prefer to live in a world where evidence matters and the efforts of science are recognized and respected. Humans would not be thriving as they are today if not for the work of scientists. Hell, we might not exist at all. Yet, it seems every effort is being made now to dismantle the structure and the foundation of safety that science has provided for all of the humans on the planet, not just U.S. citizens.
This whole anti-science and anti-intellectual worldview that has infected so many people I know is something that is hard for me to get past. The mentality that these people have leads directly to so much suffering and death. Yet, they are so in thrall to it that they can’t wait for any opportunity to express their disdain for anyone who pushes back. It feeds a dislike and, yes, often a hatred in me that I don’t want to exist. But it’s there, and little by little I guess I am coming to terms with the fact that this feeling in me is not going to change, because I know they will never release the iron-clad they hold on their mass delusion.
I don’t talk to my brother-in-law about politics anymore. I try to avoid it with my father. Both of these are smart guys: studied chemistry, physics, and software engineering at Berkeley. But they didn’t pursue education further than bachelors and they were done with that a long time ago.
So yeah, I avoid discussing politics with them, but it would be interesting to know what they think of this. For one thing, my daughter is graduating this weekend into a research job market that is now mostly elsewhere (France and elsewhere).
I think there’s a certain science enthusiast – I’m thinking of engineers – who develop anti-science attitudes out of some sort of resentment of academia, perhaps because they had exposure to academia, they did well, but didn’t necessarily like other things about it. I doubt either believes that the earth is flat, but they definitely don’t accept the theory of climate change and they’re smart enough to reason around the theory and convince themselves that it’s all nonsense.
Anyway, now my father’s granddaughter will have to pursue he research career in Europe. That’s hardly the worst fate for her, but damn it could’ve been different.
Just another data point among dozens of others that we are in one of the dumbest possible timelines.