[wmal]

For me, both questions "is math real" and "is math discovered or invented" miss the point. Math is a model of the universe in the same sense that a world map is a model of the earth.

Is a map real? Well, it is. I can see it on my desk. Is the earth real? It is too, but they are not the same. In that sense map is also not "real".

Is the map discovered? Well, it uses data that was mostly discovered, but some parts were "invented" or edited for simplification for the map to be useful.

The real question should be "is math useful" as a model. We all know most basic parts are, but some mathematicians forget that they are dealing with an imperfect model and keep finding paradoxes. It's like we would forget the imperfections caused by the mercator projection and be surprised the real world distances are not proportional to map distances.

That's the reason I always liked engineering more than maths. When programming you always "import" the libraries you need and find useful for the task. You only make sure that they are compatible with each other. Mathematicians "import" all axioms, call them maths, and are surprised they get paradoxes.

[crazygringo]

You're taking a distinct philosophical stance, but you're also being unnecessarily dismissive by claiming other stances "miss the point".

Math is nothing like a map -- maps are approximations of something real and they don't have any kind of internal consistency or complexity.

But there's a good argument that math is the fundamental nature of the universe, and mathematical discoveries lead to predictions of real-world behavior. While maps don't predict a thing.

The philosophical discussion isn't around whether math is useful for tracing the arc of a ball in the air, for which it always will be merely a useful approximation. It's more around math as the language of the universe, in things like quantum physics -- there's no "approximation" here, it's more the nature of reality itself.

And here, the philosophical questions around whether our descriptions of quantum physics are "invented" or "discovered" go quite deep, and necessarily involve the nature of human knowledge itself. For many people, these don't "miss the point" at all -- they're some of the deepest, most profoundly meaningful questions that exist.

[wmal]

> You're taking a distinct philosophical stance, but you're also being unnecessarily dismissive by claiming other stances "miss the point".

I read my comment again and I was surprised, as I did not intend this tone. I’m sorry for being dismissive and for generalising too much about mathematicians.

Could you elaborate or point me to a formulation of the “language of the universe” argument you mentioned that avoids mentioning quantum physics? I don’t understand quantum physics and I’d like to avoid falling for the quantum physics fallacy [1]

[1]: https://www.logicallyfallacious.com/logicalfallacies/Quantum...

[crazygringo]

No worries! Just wanted to make sure you were aware of other perspectives.

And a good place in general to start is always Wikipedia:

https://en.wikipedia.org/wiki/Philosophy_of_mathematics

And none of this has anything to do with the "quantum physics fallacy" at all. Philosophically, it's simply an argument about the most basic physical understanding of our universe, and right now that happens to be quantum physics.

[j2kun]

> It's more around math as the language of the universe, in things like quantum physics -- there's no "approximation" here, it's more the nature of reality itself.

Why is it that everyone thinks of mathematical models of quantum mechanics as much closer to the "nature of reality" than any other mathematical model? If anything the constant disagreements between quantum mechanics and physical models at other scales should make it clear that all the models we have are wrong by virtue of incompatibility.

[readenough]

I think the question should go even deeper. There are so many fundamental axioms that must be accepted on faith alone. The question I usually start with is "Can anyone prove that numbers exist outside of our imagination?" I not talking simply about perception. Even I believe that if I perceive that I am hit with a brick then the brick exists. We have no senses that can detect numbers. When I asked this question to any of the several mathematicians that I know, the answer has always been ~ Yeah, good question ~ and then they move on.

[jplusequalt]

Feynman has some useful words about this phenomenon of always wanting to dig deeper: https://youtu.be/36GT2zI8lVA?si=Boiqod3GXHVMyE_s

[wmal]

Why do you think we should go deeper with pointless questions? What would you do with the answer if someone provided one?

[mcphage]

> "Can anyone prove that numbers exist outside of our imagination?"

What do you mean by "exist" here?

[naasking]

> Math is a model of the universe in the same sense that a world map is a model of the earth.

Except math can hypothetically model any consistent universe, not just our universe, which kind of undercuts the argument that it uses data that was mostly discovered, or that it's merely a model.

I think the most general view is that math is the study of structure, and some structures are real (in the sense that they exist in our universe), and some are not but we can still "discover" them by selective permutation or enumeration of axioms.

[wmal]

Cartography can also model any consistent universe, and I fail to see how that changes anything for the “it’s just a model” argument.

We can permutate and enumerate symbols for mountains, rivers and roads on a piece of paper. Maybe we would even get some “interesting” results like a map of the Lords of the Rings universe. How would that change anything?

[jplusequalt]

I think you are both getting lost in the weeds trying to make this metaphor work, or not work.

Math is simply the logical conclusion of a set of conditions someone accepts as inherently true. If this, then that. Follow this logic far enough and you end up where we are today.

[naasking]

I think this conflates logic and mathematics. Some would dispute that logic underpins mathematics. Counting can be analyzed logically, but it does not in any meaningful sense seem to depend on logic.

[jplusequalt]

Sure it does. How else would you prove that one number follows or precedes another? I think you are conflating the act of physically counting with the logical foundation of our number systems.

[naasking]

It doesn't seem correct to equate mathematics with proof. If I express a mathematical construction like the whole numbers (let Whole = Zero | Succ Whole), and I build further constructions on that foundation, am I doing mathematics? If so, then it seems mathematics does not depend on logic, as logic depends on propositions and there are no propositions to be seen.

Certainly you can analyze such constructions using logic, but that's again conflating logic with mathematics. There's overlap, but they aren't strictly the same.

[naasking]

Show me a cartographic map of a 5-dimensional universe.

[goodbyesf]

> Math is a model of the universe in the same sense that a world map is a model of the earth.

That describes pre-1900s math we inherited from the greeks. With advent of non-euclidean geometry and abstract math, math is no longer bound to objective 'reality'.

[dandare]

>Math is a model of the universe

And I would dare to disagree right here. Math contains many structures that we don't know from our universe and that probably do not exist in our universe. If math is a model of universe, why is there a Mandelbrot set?

[wmal]

Yes, that is an intrinsic property of all models. They are imperfect, and we accept it as long as the models are useful for some purposes.

My map has a text written on it saying “Pacific Ocean”, yet I would not complain if I went to this place an couldn’t find a giant object in the ocean that would look like a letter P from the skies.