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Scientific theories are rarely accepted immediately. Even if the evidence for a theory is impeccable, there will be some stragglers who resist it for lack of understanding. More interesting is when a theory that ultimately turns out to be true is legitimately resisted at first due to lack of evidence. (For example, for a very long time atoms were rightly not considered a known fact, even though there were many who vigorously argued in support of them.)

Newton's laws of motion now seem "pretty obvious," but that's only because most of us were taught them so long ago. What kind of resistance did they meet at first, and what were the most legitimate counter-arguments?

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There was an opposition. The reasons were mainly philosophical. The main thing which was hard to accept was "action at a distance" through the void space. For example Huygens did not accept this. It contradicted Descartes theory which was prevalent at that time. So the question had too be decided by observations and experiments, as it always happens in science.

And it was decided in the most spectacular way. The crucial successes were: prediction of the correct shape of the Earth, explanation of inequalities of Moon motion which led to very exact predictions of the Moon position in the sky. And the perhaps the greatest: the discovery of new planets, big (Neptune) and small (asteroids). Discovery of new planets on the basis of Newton's mechanics continues to this day, by the way. I mean in other star systems, and discovery of smaller objects in the Solar system.

After the discovery of Neptune, NO SERIOUS SCIENTIST could have any doubt in the correctness of the theory. In fact we obtain new confirmations of this theory all the time.

Here I am in a strong disagreement with Conifold. Newton's mechanics is correct. Because it explains and predicts observations and experiments correctly, and with very high accuracy. It is the cornerstone of the whole physics, and one of the most successful scientific theories. It is taught nowadays at all level from elementary school to the universities, and it is still an important research topic. And will always be.

And general relativity or quantum mechanics did not diminish its value. One cannot say that "it was replaced". It was complemented with new theories.

EDIT. All theories have their limitations. Quantum mechanics does not describe gravity. General relativity has nothing to do with the structure of the atom. Newton's theory is highly successful in a very wide range of natural phenomena, and it is unlikely to be ever "replaced".

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  • $\begingroup$ Newton's theory now appears to be just a devlopment of geometry, as it does not take in account an important (empirical) fact: there is an upper limit for speed. So colinear speeds are not added as lengths. Its accuracy deteriorates with increased speeds. $\endgroup$ – sand1 Apr 6 at 8:10
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    $\begingroup$ Yes, Newton's theory holds for small speeds. But it is a CORRECT theory for small speeds. Every theory has some limitations. $\endgroup$ – Alexandre Eremenko Apr 6 at 15:44
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    $\begingroup$ What this answer says about 'replacement' of Newton's mechanics agrees with what Einstein himself wrote, see this answer: of course Einstein corrected Newton and introduced a new explanatory framework, but what he wrote about Newton coexists with that. $\endgroup$ – terry-s Apr 6 at 22:42
  • $\begingroup$ How is "Newton's mechanics is correct" in disagreement with me? Everything new and original, correct or not, faces resistance and opposition. It is so with evolution and relativity, as it was with heliocentrism, or for that matter, with geocentrism, Newton's mechanics was no exception. "Complemented" means extended without change in the original range. GR and QFT introduce corrections even there. Nor is it the basis of our picture of the world, as it used to be. So it was replaced in both senses. This is not even provocative or controversial, just banal observations. $\endgroup$ – Conifold Apr 8 at 22:34
  • $\begingroup$ @Conifold the main evidence that Newton's theory and classical mechanics were not replaced is that they are still widely used and actively studied all across science from engineering to mathematical physics. $\endgroup$ – user2723984 Apr 10 at 11:58
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Newtonian mechanics was resisted throughout its history, all the way until it was replaced by relativity and quantum mechanics. But the criticism did not so much concern the specifics of his laws of motion, there were few Aristotelians around, and, after all, they were pretty well confirmed by experiments, as their interpretations and "metaphysical" implications.

When Newton published Principia the prevailing view of physics was Cartesian, and the two of them clashed over the course of 19th century. Cartesian physics, was more qualitative, descriptive and "intuitive", in other words, it was more like the natural philosophy of old (e.g. Aristotelian or atomistic). Descartes had the luminiferous aether, and the swirling vortices in it moving things around, in place of Newton's faceless mathematical forces, including the action at a distance for gravity, which even Newton himself disliked. In the early 1700-s Cartesian physics was refurbished by Malebranche and Rohault into an alternative to Newton's. Here is from Iltis's The Decline of Cartesianism in Mechanics:

"Several aspects of Descartes' philosophy of nature were used by Cartesians in the 1720s in attacking mechanical problems. His theory of matter stated that the world was composed of three elements formed from primitive matter. The first element, which formed the material of the sun and stars, consisted of very subtle minute matter capable of moving at enormous speeds and of filling in the small spaces surrounding the other two denser forms of matter. The second element consisted of spherical particles formed from rotation of the original primitive matter. These spheres, the main constituent of celestial matter, moved in large vortices at high speeds and could transmit pressure instantaneously. The third element was coarser and slower and composed the earth and planets.

The properties and action of the spherical aether particles were used by Cartesians in explaining the action of mechanical bodies. As the aether swirled in a centrifugal vortical motion around the earth it caused continual impulses on terrestrial objects. Since the subtle matter moved faster than terrestrial matter and exerted a force toward the center, bodies above the earth would fall toward the earth's center."

By the end of 18th century the Cartesian conception was mostly abandoned, but not the spirit of natural philosophy. The torch was taken up by German romantics and their Naturphilosophie. Göthe, better known as the author of Faust, also penned Theory of Colours, that critiqued Newton's optics and replaced it with a more "poetic" theory, emphasizing the boundary between "light and darkness". Although his theory was rightly rejected by physicists, he made a number of astute observations about the human color perception that are now incorporated into chromatics. Schelling and Hegel rejected mechanistic Newtonian science as such, and planned to replace it with an imagined "better" science, see Why did Hegel hate Newton?

A seemingly technical issue that consumed a lot of attention of many famous people was the vis viva controversy, as to what constitutes the "true" quantity of motion, vis viva (now, kinetic energy) or vis mortia (now, momentum, which Descartes mistakenly believed to be mass times the magnitude of velocity), see What was the vis viva controversy? A more substantive part of it was a dispute between force-based description of physics, that Newton favored, and energy-based one, favored by Leibniz. Leibniz saw both Cartesian and Newtonian physics as too "mechanistic", unable to explain the the "source of the vitality" of matter, which his vis viva, elevated to a metaphysical status, was meant to do.

Newton's absolute space also got its share of detractors. First, Leibniz, who saw space as relational rather than a self-standing metaphysical entity, Berkeley shared similar views and offered an influential criticism of Newton's mechanics, albeit less known now than his criticism of Newton's calculus. Then Kant, who sought to produce a physical construction for the "absolute frame of reference" in almost modern spirit. He associates it with the ideal limit of taking first the frame attached to the Earth, then to the center of mass of the Solar system, etc., see Newton and Kant on Absolute Space by Friedman. These ideas were later be used by Mach to dispense with the absolute space even in the mathematical formalism, and usher in the relativistic conception, adopted and transformed by Einstein.

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  • $\begingroup$ It's amazing how similar Malebranche and Rohault's work was to modern-day crackpot theories. $\endgroup$ – Display Name Apr 6 at 3:51
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    $\begingroup$ The first sentence is simply ridiculous! Replaced?!! $\endgroup$ – Alexandre Eremenko Apr 6 at 4:38
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    $\begingroup$ Goethe wrote an adaptation of Faust into two plays -- he didn't write the original story, which had already been around for hundreds of years. $\endgroup$ – Robert Furber Apr 6 at 22:28
  • $\begingroup$ @AlexandreEremenko And yet it's true. $\endgroup$ – Conifold Apr 7 at 8:07
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    $\begingroup$ @RobertFurber True. But being based on prior myths/stories does not prevent us from saying that Sophocles wrote Oedipus, von Eschenbach wrote Parzival, Shakespeare wrote Hamlet, Moliere wrote Don Juan, Shaw wrote Pygmalion, or Brecht wrote Turandot. Possibly because their versions are particularly well-known today, e.g. Marlowe's Faust is much less known than Göthe's. $\endgroup$ – Conifold Apr 7 at 10:20

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