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"It is the only physical theory of universal content concerning which I am convinced that within the framework of the applicability of its basic concepts, it will never be overthrown." - Albert Einstein

"Nothing in life is certain except death, taxes and the second law of thermodynamics". - Seth Lloyd

“If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations — then so much the worse for Maxwell's equations. If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation." - Arthur Eddington

"“Every question or effect has the right to exist if it does not contradict the second law of thermodynamics”. - Boris Pavlovich

“A good many times I have been present at gatherings of people who, by the standards of the traditional culture, are thought highly educated and who have with considerable gusto been expressing their incredulity at the illiteracy of scientists. Once or twice I have been provoked and have asked the company how many of them could describe the second law of thermodynamics. The response was cold: it was also negative. Yet I was asking something which is the scientific equivalent of: Have you read a work of Shakespeare's?” - C.P. Snow

I find these particularly interesting but there are many others which mark the supremacy of the laws of thermodynamics over any other law ever formulated by man.

I have just begun to learn the laws of thermodynamics and it is indeed very different and "interesting" but so was Newton's laws of motion, Faraday's laws, Heisenberg's uncertainty principle, Einstein's theory of relativity, then why are laws of thermodynamics considered so immutable and supreme to other laws. What is it that makes all these great people hold them as so impactful and perpetual and makes these laws outweigh others?

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    $\begingroup$ The laws of thermodynamics have been resistant to experimental disproof for much longer than all of the others you mention. $\endgroup$
    – hBy2Py
    Feb 22, 2017 at 17:01

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The laws never outweigh each other, nor do they have to. Newton's laws of motion, Maxwell's equations of electromagnetism, Einstein's theory of relativity are all equally fundamental, in that they've never been overthrown within their respective frameworks of applicability. Sure, these frameworks have their limits: Newton fails at near-light speeds where Einstein takes over, Maxwell and Einstein fail at quantum limit. So what? Thermodynamics has its limits as well. If you don't believe this, then good luck trying to apply it to a single molecule.

If anything, the laws of thermodynamics are less fundamental, in that they are true only statistically, that is, with less precision than the rest. With relatively little effort, you can measure the mass of a body to six-digit precision. Can you do the same to its temperature?

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    $\begingroup$ Thermodynamics isn't only statistical. Various "Maxwell demons" don't break second law. $\endgroup$
    – Mithoron
    Feb 22, 2017 at 19:43
  • $\begingroup$ This doesn't seem to answer the question. The scientists quoted were remarking that they believed the Second law most strongly of all. $\endgroup$
    – MaxW
    Feb 22, 2017 at 20:14
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    $\begingroup$ @Mithoron Of course they do (that is, would do if they were possible - that's their purpose in the first place). You can prove their non-existence by assuming the said law, but that would be an example of circular logic. The true reason lies within quantum mechanics. You just can't touch a molecule so lightly as not to change its energy, yet still get the information about it. If the molecules weren't quantum objects... Imagine a "gas" of flying cars, or just a busy traffic in a city, for that matter; the Maxwell demons indeed do exist in this setting, and are working quite successfully. $\endgroup$
    – Ivan Neretin
    Feb 22, 2017 at 20:31
  • $\begingroup$ My point is that there are various implementations of original law breaking idea but they work without actually breaking anything. $\endgroup$
    – Mithoron
    Feb 22, 2017 at 23:46
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    $\begingroup$ What do you mean "Thermodynamics has its limits as well"? What are these limits? $\endgroup$
    – Georgeos Hardo
    Feb 24, 2017 at 21:43
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As Boltzmann taught us, (equilibrium) thermodynamics1 is a natural consequence of the statistical behavior arising in any macroscopic system, regardless of the details of the microscopic laws of physics followed by the constituent particles.

The nature of microscopic laws could be, e.g., non-relativistic, relativistic, classical, quantum. For the sake of thermodynamics, it doesn't matter what kind of laws are more fundamentally valid than others. At the macroscopic level, we always have the statistical behavior and hence thermodynamics. The details of the microscopic laws determine what probability distribution to use when doing statistics, but the fact that we have to do statistics is unchanged.

The above having been said, thermodynamics really has a unique status compared to usual microscopic laws of physics. It doesn't mean that thermodynamics in any way outweighs other laws. Thermodynamics is just in a different ballpark, and in that ballpark, there is really nothing else.

1It should be noted that equilibrium thermodynamics is applicable only to systems that can equilibrate, i.e., whose constituent particles can jiggle around in a sufficiently random fashion during the time scale of observation.

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    $\begingroup$ This. The connection between entropy and state counting makes the 2nd law intimately related to ... arithmetic. Which is pretty basic. To be sure there are a few other requirements, but they turn out to be very common. (And Einstein even restricted his statement to cases where those other requirements are met.) $\endgroup$
    – dmckee --- ex-moderator kitten
    Jan 6, 2018 at 19:56
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The scientists quoted were remarking that they believed the second law most strongly of all. The reason is that the second law corresponds to real world experience. Scientists for instance believe that perpetual motion machines don't exist and accept that as evidence the second law must be true. (If a perpetual motion machine were possible then you could use such a machine to create "free" energy by hooking it up to an electrical generator.)

The notion is that humans can't see the lines of force in an electric or magnetic field. We can do experiments to detect relativity, but it outside our day to day experiences. So those theories are abstract in nature.

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  • $\begingroup$ This describes one downstream implication of the second law, but doesn't answer the question of why the second law is given such deference. $\endgroup$
    – hBy2Py
    Feb 22, 2017 at 18:51
  • $\begingroup$ @hBy2Py - I thought it would be intuitively obvious to the casual observer that perpetual motion machines cannot exist. If they did, then they would violate the Second Law and thus prove that the second law was invalid. $\endgroup$
    – MaxW
    Feb 22, 2017 at 18:57
  • $\begingroup$ Abstract from here: "Perpetual motion will not go away, and it continues to fascinate inventors. It simultaneously appeals to the best and worst sides of human nature: the urge to transcend the limits of the possible, against the desire to get something for nothing. Perpetual motion machines are scientifically impossible, but that does not stop a steady stream of applications attempting to patent them." $\endgroup$
    – hBy2Py
    Feb 22, 2017 at 19:09
  • $\begingroup$ Unfortunately, unless one has been trained in the laws of thermodynamics, there is no immediate and obvious reason why they should not be possible. Once one has been trained, the conditioning for reflexive rejection of perpetual motion concepts is so strong that it's hard to imagine it not being instinctively impossible. $\endgroup$
    – hBy2Py
    Feb 22, 2017 at 19:10
  • $\begingroup$ @hBy2Py - So we're having a violent agreement? The quotes were from scientists who were trained... $\endgroup$
    – MaxW
    Feb 22, 2017 at 19:20

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