Harry Smith, from the series Zodiac, 1978
does anyone have some evidence/sources for “newton didn’t discover anything, he read indian scientists”? when i google it i find some vaguely indian-nationalist sources talking about how indian scientists (either brahmagupta II or bhaskaracharya) had discovered gravity 1000 years earlier. it definitely seems to be the case that the mathematician brahmagupta wrote about earth having an attractive force that makes things fall down, but (1) did he mathematically model it? i thought that was one of newton’s big innovations, building on earlier european and islamic theories about gravity, and (2) did newton know about or read brahmagupta? people independently come up with the same ideas all the time, there’s enough credit to go around
ALT
ALTwell, i guess i need to do my own research.
the thing is, people have made the exact same claim about loads of medieval scientists and mathematicians, including ibn sina, bhaskaracharya, aryabhata, brahmagupta ii, ibn al-haytham, and al-khazini. that's because yes, dozens of people made advances in the study of gravity before newton. a few of the others are abu'l-barakāt al-baghdādī, al-biruni, heraclitus, aristotle, vitruvius, john philoponus, albert of saxony, nicole oresme, leonardo da vinci, petrus apianus, galileo galilei, and johannes kepler.
some of these people's advancements did turn out to be correct, and some of their work did influence newton. that is part of why it's very wrong to say that
ALTbut when people claim any of them as the one Real Discoverer of gravity whose work was apparently Stolen by newton, the correction is just as wrong as the misconception.
that’s because both of them are just not how scientific discoveries work, like at all. it's almost always a collection of different people in different scientific traditions arguing with each other and incrementally figuring out more and more as they get better evidence. standing on the shoulders of giants, as the saying goes
there’s been a number of posts with different stages of this telephone game, so it’s not hard to see how it happened. pushed by factors that range from clickbait to nationalism to diversifying the history of science, people have accidentally gone from “education and common knowledge in the western world tend to focus on european science, unfairly neglecting the importance of premodern indian and arabic science” (true) to “the myth of newton being inspired by an apple is an attempt to cover up the fact that he was inspired by previous scientists, including some who wrote in arabic” (conspiratorial linkage between facts) to “newton didn’t discover shit, he just stole ideas from scientists of color” (absurd and wrong)
I think people fail to understand what Newton was even notable for (re: gravity specifically; Newton was notable for many things, but we're focusing on that right now), and it contributes to this sort of nonsense.
If you hear "Newton discovered gravity" and "Gravity is the force that attracts objects to planet Earth, making them fall", it might sound plausible to you that a sentence from Brahmagupta saying "A body falls towards the Earth as it is the nature of the Earth to attract bodies just as it in the nature of the water to flow" is the same thing. And then you get angry about people crediting a European with things an Indian mathematician was saying a thousand years earlier.
But "earth attracts things" is not what Newton is credited with discovering, and that discovery could not have come from reading someone else's work, because genuinely nobody knew that until he figured it out. (the apple story is also obviously false, btw, and tempting for very similar reasons)
Newton's law of universal gravitation says that any two objects with mass experience an attractive force that is proportional to their masses and inversely proportional to the square of the distance between them. Newton figured out that this law, combined with his laws of motion, says that if you two objects one much more massive than the other (like, say, a planet and the sun), the small one would orbit the big one in an ellipse exactly as described in Kepler's laws, and also make ordinary things fall to the ground.
There's a lot to be said about the significance of this, but I want to focus on the precision; Newton didn't just say "objects attract each other". If objects attracted each other but the law was not G*m1*m2/r^2 (1), then you would not observe the elliptical orbits of the planets, you'd observe something else. It is a crucial part of Newton's discovery that he had a very precise mathematical formulation of how strong gravity is, that he had the concept of what it means for something to be a force (an concept that only makes sense within Newton's laws of motion), that he had the mathematical ability to take that law and the concept of a force and derive elliptical motion from it.
Newton is not notable for saying "things fall to the ground because the Earth attracts them". People had said this before. If he'd stolen his actual discovery from an Indian or Arab scholar, you should be able to point to things in their work like, say, a heliocentric model of the solar system with the planets in elliptical orbits, and some expression of that whole G*m1*m2/r^2 law (not in those symbols, obviously, but it should be written out somehow). You would not be tempted to point at a sentence saying "Earth attracts things" if you knew what Newton actually discovered re: gravity and expected your audience to do too.
(1) yes, general relativity changes things, etc. Newton was approximately correct, and that approximation is good enough for safely landing robots on other planets.
The key observation that Newton contributed, the one that was truly revolutionary (haha), the one he is known for, is the fact that the force is universal. The insight wasn't "apples fall to the earth bc of a force" (he took that from Galileo and others) and it wasn't "the earth orbits the sun bc of a force" (he may have been inspired by Hooke's work on springs for that, and we know Hooke was working on this very statement, he just couldn't figure out why ellipses).
The key insight that Newton contributed was "apples fall to the earth bc of the same force that makes the moon orbit the earth, which is ALSO the same force that makes the earth orbit the sun, and here is what that force is mathematically, and here is a set of rules for how to take that mathematical description and turn it into predictions about motion". It's the universality and the mathematical description of it that was groundbreaking. That's why he called his book the Principia Mathematica. That's the point. The fact that the heavens followed the same laws as the earth, and that there was a language you could use to precisely describe those laws.
If I could describe what was so revolutionary about Newton's "discovery of gravity" in one sentence, I would say "He figured out that math is the language that best and most precisely describes the singular set of rules that apply to the entirety of the universe, whether they be here on earth or up in the cosmos".
I’ve heard people say this same sort of thing about Darwin so many times. “Darwin didn’t come up with anything, X guy from some other culture knew that different species were related thousands of years before he -- ” yeah no shit, so did the rest of England. So did the ancient Greeks. That’s not the part that Darwin came up with. (People who do want to know about uncredited predecessors to Darwin’s work should read Darwin’s Ghosts, it’s a great book, but that’s another topic.)
Science history is full of people stealing or miscrediting work, but if you want to find that kind of thing, it helps to actually be familiar with what these scientists are credited with discovering. Because it’s never vaguely saying, “hey, here’s a commonly observable thing that people have known about forever. Now give me some awards.” You cannot understand the science history if you’re not at least passingly familiar with the science.
The Crushing Weight of Not Knowing If There Is a Task
im starting to think this crushing weight is not about the tasks
