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  3. I don't want to formalize any of my work on mathematics.

I don't want to formalize any of my work on mathematics.

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  • johncarlosbaez@mathstodon.xyzJ johncarlosbaez@mathstodon.xyz

    I don't want to formalize any of my work on mathematics. First because, as Emily Riehl notes, formalization tends to impose consensus. And second, because I find it boring. It steals time from creative thought to nail things down with more rigidity than I need or want.

    Kevin Buzzard says "It forces you to think about mathematics in the right way." But there is no such thing as "the" right way to think about mathematics - and certainly not one that can be forced on us.

    Link Preview Image
    In Math, Rigor Is Vital. But Are Digitized Proofs Taking It Too Far? | Quanta Magazine

    The quest to make mathematics rigorous has a long and spotty history — one mathematicians can learn from as they push to formalize everything in the computer program Lean.

    favicon

    Quanta Magazine (www.quantamagazine.org)

    activemouse@mathstodon.xyzA This user is from outside of this forum
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    activemouse@mathstodon.xyz
    wrote last edited by
    #29

    @johncarlosbaez by "formalize" do you mean, "rewrite in a computer-checked proof system"?

    The definition of a function as a set of ordered pairs was/is a formalisation, but not computer-checked; it just allows us to state in simpler terms the properties a function needs to have.

    johncarlosbaez@mathstodon.xyzJ 1 Reply Last reply
    0
    • activemouse@mathstodon.xyzA activemouse@mathstodon.xyz

      @johncarlosbaez by "formalize" do you mean, "rewrite in a computer-checked proof system"?

      The definition of a function as a set of ordered pairs was/is a formalisation, but not computer-checked; it just allows us to state in simpler terms the properties a function needs to have.

      johncarlosbaez@mathstodon.xyzJ This user is from outside of this forum
      johncarlosbaez@mathstodon.xyzJ This user is from outside of this forum
      johncarlosbaez@mathstodon.xyz
      wrote last edited by
      #30

      @ActiveMouse - yes, that's what I mean. I grew up in the era where it had a different meaning, and that meaning is still common. but now a lot of mathematicians use "formalize" to mean "prove using a proof assistant such as Lean or Rocq".

      Link Preview Image
      What is the endgoal of formalising mathematics?

      Recently, I've become interested in proof assistants such as Lean, Coq, Isabelle, and the drive from many mathematicians (Kevin Buzzard, Tom Hales, Metamath, etc) to formalise all of mathematics in...

      favicon

      MathOverflow (mathoverflow.net)

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      • johncarlosbaez@mathstodon.xyzJ johncarlosbaez@mathstodon.xyz

        @dougmerritt - You got my point. Working in Lean or any computer system for formalization, you need to submit to the already laid down approaches, or spend a lot of time rewriting things.

        I added a quote from Kevin Buzzard to emphasize the problem:

        Kevin Buzzard says "It [formalization? Lean?] forces you to think about mathematics in the right way."

        But there's no such thing as "the" right way!

        maxpool@mathstodon.xyzM This user is from outside of this forum
        maxpool@mathstodon.xyzM This user is from outside of this forum
        maxpool@mathstodon.xyz
        wrote last edited by
        #31

        @johncarlosbaez @dougmerritt

        This is just the beginning.

        Current systems are the FORTRAN and Pascal of proof systems; they are for building pyramids--imposing, breathtaking, static structures built by armies pushing heavy blocks into place.

        What we need is for someone to invent the Lisp of proof systems. Something that helps individuals to think new thoughts.

        dougmerritt@mathstodon.xyzD dlakelan@mastodon.sdf.orgD 2 Replies Last reply
        0
        • maxpool@mathstodon.xyzM maxpool@mathstodon.xyz

          @johncarlosbaez @dougmerritt

          This is just the beginning.

          Current systems are the FORTRAN and Pascal of proof systems; they are for building pyramids--imposing, breathtaking, static structures built by armies pushing heavy blocks into place.

          What we need is for someone to invent the Lisp of proof systems. Something that helps individuals to think new thoughts.

          dougmerritt@mathstodon.xyzD This user is from outside of this forum
          dougmerritt@mathstodon.xyzD This user is from outside of this forum
          dougmerritt@mathstodon.xyz
          wrote last edited by
          #32

          @maxpool @johncarlosbaez
          Yes, well, moving past John's point:

          Easier said than done. Current things like Lean are lots better than the systems of years ago, but -- do you have any specific ideas?

          I used to follow that area of technology, but I somewhat burned out on it. For now, Terry Tao et al is getting good mileage out of Lean.

          I suppose there's some analogy with the period of shift from Peano axioms to ZFC and beyond.

          johncarlosbaez@mathstodon.xyzJ 1 Reply Last reply
          0
          • dougmerritt@mathstodon.xyzD dougmerritt@mathstodon.xyz

            @maxpool @johncarlosbaez
            Yes, well, moving past John's point:

            Easier said than done. Current things like Lean are lots better than the systems of years ago, but -- do you have any specific ideas?

            I used to follow that area of technology, but I somewhat burned out on it. For now, Terry Tao et al is getting good mileage out of Lean.

            I suppose there's some analogy with the period of shift from Peano axioms to ZFC and beyond.

            johncarlosbaez@mathstodon.xyzJ This user is from outside of this forum
            johncarlosbaez@mathstodon.xyzJ This user is from outside of this forum
            johncarlosbaez@mathstodon.xyz
            wrote last edited by
            #33

            @dougmerritt - I follow some people who are into formalization, logic and type theory more sophisticated than Lean: @MartinEscardo, @andrejbauer, @pigworker and @JacquesC2 leap to mind. They're the ones to answer your question.

            jacquesc2@types.plJ andrejbauer@mathstodon.xyzA 2 Replies Last reply
            0
            • johncarlosbaez@mathstodon.xyzJ johncarlosbaez@mathstodon.xyz

              @dougmerritt - You got my point. Working in Lean or any computer system for formalization, you need to submit to the already laid down approaches, or spend a lot of time rewriting things.

              I added a quote from Kevin Buzzard to emphasize the problem:

              Kevin Buzzard says "It [formalization? Lean?] forces you to think about mathematics in the right way."

              But there's no such thing as "the" right way!

              bgalehouse@mathstodon.xyzB This user is from outside of this forum
              bgalehouse@mathstodon.xyzB This user is from outside of this forum
              bgalehouse@mathstodon.xyz
              wrote last edited by
              #34

              @johncarlosbaez @dougmerritt Formalism exists to provide rigor and math without rigor isn't really math. But you are right that rigor can be developed in multiple ways, also that computer verified formulations are not as rich as the math literature at large.

              I wonder if generative AI will lead to richer computer verified formulations though. I keep hearing about how the AI assisted with a problem that people find interesting. What happens when we train an AI to recognize results that people find interesting and tell it to go find new results of that sort?

              1 Reply Last reply
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              • johncarlosbaez@mathstodon.xyzJ johncarlosbaez@mathstodon.xyz

                I don't want to formalize any of my work on mathematics. First because, as Emily Riehl notes, formalization tends to impose consensus. And second, because I find it boring. It steals time from creative thought to nail things down with more rigidity than I need or want.

                Kevin Buzzard says "It forces you to think about mathematics in the right way." But there is no such thing as "the" right way to think about mathematics - and certainly not one that can be forced on us.

                Link Preview Image
                In Math, Rigor Is Vital. But Are Digitized Proofs Taking It Too Far? | Quanta Magazine

                The quest to make mathematics rigorous has a long and spotty history — one mathematicians can learn from as they push to formalize everything in the computer program Lean.

                favicon

                Quanta Magazine (www.quantamagazine.org)

                kel@mastodon.onlineK This user is from outside of this forum
                kel@mastodon.onlineK This user is from outside of this forum
                kel@mastodon.online
                wrote last edited by
                #35

                @johncarlosbaez

                I agree,

                Many years ago, um, last century...lol I stumbled over Vedic Mathematics and had all my illusions shattered about there being a right way to do maths.

                It's so utterly different to anything I was taught in school, and yet it's easier and it works 🤷

                Link Preview Image
                Vedic Mathematics - Wikipedia

                favicon

                (en.wikipedia.org)

                1 Reply Last reply
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                • johncarlosbaez@mathstodon.xyzJ johncarlosbaez@mathstodon.xyz

                  @pigworker - Good! But to get anywhere with formalizing big theorems in Lean, the topic mainly discussed in this article, you're pressured to work within that system.

                  L This user is from outside of this forum
                  L This user is from outside of this forum
                  liuyao@mathstodon.xyz
                  wrote last edited by
                  #36

                  @johncarlosbaez @pigworker Or wait for a year or two, and an AI agent will do everything from the ground up, bypassing/recreating mathlib.

                  1 Reply Last reply
                  0
                  • johncarlosbaez@mathstodon.xyzJ johncarlosbaez@mathstodon.xyz

                    @dougmerritt - I follow some people who are into formalization, logic and type theory more sophisticated than Lean: @MartinEscardo, @andrejbauer, @pigworker and @JacquesC2 leap to mind. They're the ones to answer your question.

                    jacquesc2@types.plJ This user is from outside of this forum
                    jacquesc2@types.plJ This user is from outside of this forum
                    jacquesc2@types.pl
                    wrote last edited by
                    #37

                    @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker I can give it a try.

                    First: Lean and Mathlib embody a very particular philosophy. Lean 4 aims to be "practical", which is mainly code for 'allowing lots of automation'. It cuts some serious corners to achieve that (others have written about that at length). Mathlib chooses to be a 'monorepo' (which is laudable indeed IMHO). The combination of Lean's technology choices and the monorepo decision is what forces 'consensus'.

                    jacquesc2@types.plJ 1 Reply Last reply
                    0
                    • jacquesc2@types.plJ jacquesc2@types.pl

                      @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker I can give it a try.

                      First: Lean and Mathlib embody a very particular philosophy. Lean 4 aims to be "practical", which is mainly code for 'allowing lots of automation'. It cuts some serious corners to achieve that (others have written about that at length). Mathlib chooses to be a 'monorepo' (which is laudable indeed IMHO). The combination of Lean's technology choices and the monorepo decision is what forces 'consensus'.

                      jacquesc2@types.plJ This user is from outside of this forum
                      jacquesc2@types.plJ This user is from outside of this forum
                      jacquesc2@types.pl
                      wrote last edited by
                      #38

                      @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker I would compare Lean+Mathlib to Java rather than FORTRAN and Pascal: Java is just as boring a PL as others, but it is a much stronger ecosystem (IDEs, libraries, tutorials, etc). Thus developers have a much better experience using Lean+Mathlib and the surrounding ecosystem (blueprints are super cool, as just one example).

                      In my mind, it is purely 'social forces' that has made and is making Lean+Mathlib the apparent winner. And that has snowballed - almost to the point of smothering everything else, which is extremely dangerous for innovation.

                      jacquesc2@types.plJ markusde@mathstodon.xyzM 2 Replies Last reply
                      0
                      • jacquesc2@types.plJ jacquesc2@types.pl

                        @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker I would compare Lean+Mathlib to Java rather than FORTRAN and Pascal: Java is just as boring a PL as others, but it is a much stronger ecosystem (IDEs, libraries, tutorials, etc). Thus developers have a much better experience using Lean+Mathlib and the surrounding ecosystem (blueprints are super cool, as just one example).

                        In my mind, it is purely 'social forces' that has made and is making Lean+Mathlib the apparent winner. And that has snowballed - almost to the point of smothering everything else, which is extremely dangerous for innovation.

                        jacquesc2@types.plJ This user is from outside of this forum
                        jacquesc2@types.plJ This user is from outside of this forum
                        jacquesc2@types.pl
                        wrote last edited by
                        #39

                        @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker Are there specific ideas around to make things better? Absolutely! Heck, there are old ideas (Epigram comes to mind, but even Automath has not been fully mined yet) that are still not implemented.

                        I will continue later - need to attend to other things right now.

                        jacquesc2@types.plJ 1 Reply Last reply
                        0
                        • johncarlosbaez@mathstodon.xyzJ johncarlosbaez@mathstodon.xyz

                          @dougmerritt - I follow some people who are into formalization, logic and type theory more sophisticated than Lean: @MartinEscardo, @andrejbauer, @pigworker and @JacquesC2 leap to mind. They're the ones to answer your question.

                          andrejbauer@mathstodon.xyzA This user is from outside of this forum
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                          andrejbauer@mathstodon.xyz
                          wrote last edited by
                          #40

                          @johncarlosbaez @dougmerritt @MartinEscardo @JacquesC2 @pigworker Somewhat unexpectedly, I find myself on the same side as @xenaproject on this one, I suppose because I read "the right way" differently from @johncarlosbaez

                          Formalized mathematics makes us think "the right way" in the sense that it requires mental hygiene, it encourages better organization, it invites abstraction, and it demands honesty.

                          Formalized mathematics does not at all impose "One and Only Truth", nor does it "nail things down with rigidity" or "impose concensus". Those are impressions that an outsider might get by observing how, for the first time, some mathematicians have banded together to produce the largest library of formalized mathematics in history. But let's be honest, it's miniscule.

                          Even within a single proof assistant, there is a great deal of freedom of exploration of foundations, and there are many different ways to formalize any given topic. Not to mention that having several proof assistants, each peddling its own foundation, has only contributed to plurality of mathematical thought.

                          Current tools are relatively immature and do indeed steal time from creative thought to some degree, although people who are proficient in their use regularly explore mathematics with proof assistants (for example @MartinEscardo and myself), testifying to their creative potential.

                          Finally, any fear that Mathlib and Lean will dominate mathematical thought, or even just formalized mathematics, is a hollow one. Mathlib will soon be left in the dust of history, but it will always be remembered as the project that brought formalized mathematics from the fringes of computer science to the mainstream of mathematics.

                          markusde@mathstodon.xyzM leonardom@mathstodon.xyzL martinescardo@mathstodon.xyzM johncarlosbaez@mathstodon.xyzJ chrisamaphone@hci.socialC 5 Replies Last reply
                          0
                          • jacquesc2@types.plJ jacquesc2@types.pl

                            @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker I would compare Lean+Mathlib to Java rather than FORTRAN and Pascal: Java is just as boring a PL as others, but it is a much stronger ecosystem (IDEs, libraries, tutorials, etc). Thus developers have a much better experience using Lean+Mathlib and the surrounding ecosystem (blueprints are super cool, as just one example).

                            In my mind, it is purely 'social forces' that has made and is making Lean+Mathlib the apparent winner. And that has snowballed - almost to the point of smothering everything else, which is extremely dangerous for innovation.

                            markusde@mathstodon.xyzM This user is from outside of this forum
                            markusde@mathstodon.xyzM This user is from outside of this forum
                            markusde@mathstodon.xyz
                            wrote last edited by
                            #41

                            @JacquesC2 @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker Lean is worse, but, infamously, https://en.wikipedia.org/wiki/Worse_is_better

                            sandmouth@types.plS Y 2 Replies Last reply
                            0
                            • jacquesc2@types.plJ jacquesc2@types.pl

                              @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker Are there specific ideas around to make things better? Absolutely! Heck, there are old ideas (Epigram comes to mind, but even Automath has not been fully mined yet) that are still not implemented.

                              I will continue later - need to attend to other things right now.

                              jacquesc2@types.plJ This user is from outside of this forum
                              jacquesc2@types.plJ This user is from outside of this forum
                              jacquesc2@types.pl
                              wrote last edited by
                              #42

                              @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker I agree with @andrejbauer 's take, including his skepticism of my comments on Lean choking things off: we're talking (implicitly) about different time scales. I'm witnessing a current funnelling of resources, which will cause short-term pain. Indeed this is unlikely to remain 'forever'.

                              jacquesc2@types.plJ 1 Reply Last reply
                              0
                              • andrejbauer@mathstodon.xyzA andrejbauer@mathstodon.xyz

                                @johncarlosbaez @dougmerritt @MartinEscardo @JacquesC2 @pigworker Somewhat unexpectedly, I find myself on the same side as @xenaproject on this one, I suppose because I read "the right way" differently from @johncarlosbaez

                                Formalized mathematics makes us think "the right way" in the sense that it requires mental hygiene, it encourages better organization, it invites abstraction, and it demands honesty.

                                Formalized mathematics does not at all impose "One and Only Truth", nor does it "nail things down with rigidity" or "impose concensus". Those are impressions that an outsider might get by observing how, for the first time, some mathematicians have banded together to produce the largest library of formalized mathematics in history. But let's be honest, it's miniscule.

                                Even within a single proof assistant, there is a great deal of freedom of exploration of foundations, and there are many different ways to formalize any given topic. Not to mention that having several proof assistants, each peddling its own foundation, has only contributed to plurality of mathematical thought.

                                Current tools are relatively immature and do indeed steal time from creative thought to some degree, although people who are proficient in their use regularly explore mathematics with proof assistants (for example @MartinEscardo and myself), testifying to their creative potential.

                                Finally, any fear that Mathlib and Lean will dominate mathematical thought, or even just formalized mathematics, is a hollow one. Mathlib will soon be left in the dust of history, but it will always be remembered as the project that brought formalized mathematics from the fringes of computer science to the mainstream of mathematics.

                                markusde@mathstodon.xyzM This user is from outside of this forum
                                markusde@mathstodon.xyzM This user is from outside of this forum
                                markusde@mathstodon.xyz
                                wrote last edited by
                                #43

                                @andrejbauer @johncarlosbaez @dougmerritt @MartinEscardo @JacquesC2 @pigworker @xenaproject

                                > Mathlib will soon be left in the dust of history

                                Totally. Even on a technical level, having one dominant math library does not signal the degradation of the field. The other day I learned about [1] for automatically porting Lean definitions to Rocq. This project now gets to start with targeting a big, consistent library of formalized math, and even if the Mathlib people won't care that's still an great thing for the field!

                                [1] https://github.com/rocq-community/rocq-lean-import

                                mevenlennonbertrand@lipn.infoM 1 Reply Last reply
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                                • markusde@mathstodon.xyzM markusde@mathstodon.xyz

                                  @andrejbauer @johncarlosbaez @dougmerritt @MartinEscardo @JacquesC2 @pigworker @xenaproject

                                  > Mathlib will soon be left in the dust of history

                                  Totally. Even on a technical level, having one dominant math library does not signal the degradation of the field. The other day I learned about [1] for automatically porting Lean definitions to Rocq. This project now gets to start with targeting a big, consistent library of formalized math, and even if the Mathlib people won't care that's still an great thing for the field!

                                  [1] https://github.com/rocq-community/rocq-lean-import

                                  mevenlennonbertrand@lipn.infoM This user is from outside of this forum
                                  mevenlennonbertrand@lipn.infoM This user is from outside of this forum
                                  mevenlennonbertrand@lipn.info
                                  wrote last edited by
                                  #44

                                  @markusde Have you seen what can be done with this nowadays https://theoremlabs.com/blog/lf-lean/ ?

                                  markusde@mathstodon.xyzM 1 Reply Last reply
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                                  • mevenlennonbertrand@lipn.infoM mevenlennonbertrand@lipn.info

                                    @markusde Have you seen what can be done with this nowadays https://theoremlabs.com/blog/lf-lean/ ?

                                    markusde@mathstodon.xyzM This user is from outside of this forum
                                    markusde@mathstodon.xyzM This user is from outside of this forum
                                    markusde@mathstodon.xyz
                                    wrote last edited by
                                    #45

                                    @mevenlennonbertrand I've read that article rocq-lean-import was the only interesting thing in it

                                    markusde@mathstodon.xyzM 1 Reply Last reply
                                    0
                                    • jacquesc2@types.plJ jacquesc2@types.pl

                                      @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker I agree with @andrejbauer 's take, including his skepticism of my comments on Lean choking things off: we're talking (implicitly) about different time scales. I'm witnessing a current funnelling of resources, which will cause short-term pain. Indeed this is unlikely to remain 'forever'.

                                      jacquesc2@types.plJ This user is from outside of this forum
                                      jacquesc2@types.plJ This user is from outside of this forum
                                      jacquesc2@types.pl
                                      wrote last edited by
                                      #46

                                      @johncarlosbaez @dougmerritt @MartinEscardo @andrejbauer @pigworker On the more optimistic side:

                                      • there is a lot of structure to mathematics, which is currently not very well leveraged, i.e. Universal Algebra and its many generalizations. But people are working on that (myself included).
                                      • regardless of what some say, there is a lot of 'computational mathematics', which is currently not well supported by any system, and essentially eschewed by Lean+Mathlib. That requires thinking differently. Again, people are working on that.
                                      • in fact, there is quite a bit more to math in general -- see the Tetrapod approach for one.

                                      To me, what's really missing are experts in designing UX having a solid look at mechanized mathematics tools. For that to bear fruit, experts in requirements analysis need to better understand the full "mathematics workflow" -- where proof is just one small aspect. It might indeed be the most time-consuming part, but it is not necessarily where the most value lies. [See LaTeX as an example of a strong value proposition that has completely changed the practice of mathematics, but in a surreptitious way, as it is essentially invisible wrt "mathematical thought". Its effect is no less important.]

                                      jacquesc2@types.plJ 1 Reply Last reply
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                                      • markusde@mathstodon.xyzM markusde@mathstodon.xyz

                                        @mevenlennonbertrand I've read that article rocq-lean-import was the only interesting thing in it

                                        markusde@mathstodon.xyzM This user is from outside of this forum
                                        markusde@mathstodon.xyzM This user is from outside of this forum
                                        markusde@mathstodon.xyz
                                        wrote last edited by
                                        #47

                                        @mevenlennonbertrand Porting a bunch of theorem statements and then saying it's "verified" is... bold

                                        mevenlennonbertrand@lipn.infoM 1 Reply Last reply
                                        0
                                        • maxpool@mathstodon.xyzM maxpool@mathstodon.xyz

                                          @johncarlosbaez @dougmerritt

                                          This is just the beginning.

                                          Current systems are the FORTRAN and Pascal of proof systems; they are for building pyramids--imposing, breathtaking, static structures built by armies pushing heavy blocks into place.

                                          What we need is for someone to invent the Lisp of proof systems. Something that helps individuals to think new thoughts.

                                          dlakelan@mastodon.sdf.orgD This user is from outside of this forum
                                          dlakelan@mastodon.sdf.orgD This user is from outside of this forum
                                          dlakelan@mastodon.sdf.org
                                          wrote last edited by
                                          #48

                                          @maxpool @johncarlosbaez @dougmerritt

                                          I mean, Maxima was literally written in the late 60's in LISP to give people help thinking new thoughts (beyond what they could reasonably accurately do by hand)

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