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If Math is Based on Unprovable Axioms and can't be Proven - Why Does Math "Work" so Well?

I have heard that both Mathematics and Religions are based on "axioms" that are by definition unprovable. I have also heard some people argue that Mathematics, like Religion - only provides us with a logical framework to interpret the world with:

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If the above is true - why has mathematics (a system of beliefs based on unprovable axioms) proved to be so effective in understanding, analyzing and predicting the behavior of systems and phenomena in the world; whereas the same can not be said about religion (also a system of beliefs based on unprovable axioms)?

In the field of Probability, Kolmogorov's Axioms make fundamentally unprovable statements such as "If A is a subset of, or equal to B, then the probability of A is less than, or equal to the probability of B." These Axioms are regarded as being established, accepted, and self-evidently true - and also serve as a premise or starting point for further reasoning and arguments. In Zermelo-Fraenkel Set Theory, the "Axiom of Union" states that "for any set of sets F there is a set A containing every element that is a member of some member of F" - the legitimacy and the validity of this axiom is generally not up for debate, it is generally considered as "infallible" regardless of your attitudes towards it. The same way, ancient religions made similar unprovable statements that were accepted at the time and also considered as starting points for further reasonings and arguments, such as "an afterlife self-evidently exists and the ratio of your soul's weight to the weight of a feather will decide your position in this afterlife". These statements were also considered to be infallible, regardless of attitudes held towards them.

Yet as we all know, Kolmogorov's Axioms along with other collections of axioms, characterize a system of beliefs (i.e. mathematics) that has been shown to be very useful in consistently and accurately understanding, analyzing and predicting the behavior of systems and phenomena in the world (e.g. science, engineering, technology) - so much so, that mathematics almost appear to be "objectively true" and pass off as unquestioned and "factual knowledge" in our everyday life. Is this (i.e. the power, achievements and the reputation of mathematics) attributable to the fact that perhaps our world in it's su generis form might actually have an underlying mathematical structure and we have correctly identified parts of this underlying mathematical structure and created a set of axioms that is consistent with this mathematical structure? Or is mathematics at it's fundamental level no different than mystical rain dance rituals based on unprovable commandments and tautologies, and it's plethora of successful implementations over the past thousands of years merely an inconsequential result? Are deluges and rain floods understandable through man's turbulent relationship with some God - or are they understandable through atmospheric weather patterns modelled by systems of differential equations?

Even though Godel's Incompleteness Theorem exposed jarring flaws in mathematics as a whole, revealing that "a complete and consistent set of axioms for all mathematics is impossible", - why has mathematics, albeit based on a unprovable axioms, managed to evade the eventual pitfalls of other axiomatic based systems, and managed to work so "well" over the years?

stats_noob
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    Relaed. Try searching "unreasonable effectiveness of mathematics" (a 1960 essay by Eugene Wigner, and much subsequent commentary) – Gerald Edgar May 22 '23 at 08:39
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    Mathematics is not a system of beliefs, it is a system for deriving logical consequences (theorems) from basic beliefs (axioms). So "complete and consistent set of axioms for all mathematics" is pointless, and is not what Godel's theorem is about anyway. Mathematics is only effective in application to phenomena in the world when, and to the extent that, those basic beliefs, like Euclidean postulates, Newton's laws or postulates of quantum mechanics, match the phenomena. And while such beliefs cannot be proven logically, they can be and are confirmed by empirical evidence gathered by science. – Conifold May 22 '23 at 11:44
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    Is there anything not based on "unprovable axioms"? It seems to me that you could also ask this about even more fundamental things, such as the existence of anything outside of our (my) self-awareness, the existence of any actual physical laws/rules governing our universe (see my 2nd and 3rd comments to this Academia SE question), the existence of logical reasoning of any kind that isn't based on how our universe operates (see this Mathematics SE answer), etc. – Dave L Renfro May 22 '23 at 13:03
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    "I have heard that both Mathematics and Religions are based on "axioms" " Really? What are the "axioms" for the most relevant Religions? – Mauro ALLEGRANZA May 22 '23 at 14:22
  • "Godel's Incompleteness Theorem did not exposed jarring flaws in mathematics as a whole" – Mauro ALLEGRANZA May 23 '23 at 08:16
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    For an approach to the issue you can start with Wigner's The Unreasonable Effectiveness of Mathematics in the Natural Sciences (1960). Available here. – Mauro ALLEGRANZA May 23 '23 at 08:18

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Axioms in mathematics are not arbitrary statements; they are abstractions of everyday experience or physical laws (or other laws of nature). Consider two examples.

  1. Axioms and postulates of Euclid describing lines in the plane or in the space. These are abstractions of the properties of light rays (and stretched ropes). All these properties are confirmed by millennia of our experience. Until 19 century everyone actually thought that Euclidean geometry describes the real space in which we live.

  2. The axioms of real numbers come from the analysis of the procedure of measuring.

  3. Probability. Original development of probability was stimulated by analysis of games of chance, statistics, insurance and such phenomena. Later statistical physics came into play. The axioms of probability that we are using now, is the result of this long development.

So most of mathematics is deeply rooted in the study of the real world. And this explains its effectiveness in describing this real world.

Alexandre Eremenko
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    Excellent points. If you added (and mildly expanded) @Gerald 's point about Winger's "unreasonable effectiveness of mathematics" you'd have a pretty complete answer. – Mark Olson May 22 '23 at 12:48
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    @Mark Olson: of course some mystery remains here, and I am as puzzled as Wigner was. And I can also mention the article of D. Ruelle on a related subject "Is our mathematics natural" in the Bull. AMS, https://www.ihes.fr/~ruelle/PUBLICATIONS/%5B94%5D.pdf – Alexandre Eremenko May 23 '23 at 06:59