Hi, AMoura, thats me again. I think that the main problem with computer languages is not lack of features. My major concern about computer languages is that most of them do not keep backward compatibility. I liked the _Yi_ text editor, which happened to be written in Haskell. Do you know why I quit using the _Yi_ editor? Because I could not compile it anymore.
There are many pieces of software around that people stopped using simply because developers were not able to build the applications anymore. Consider the Daisy Model, which is so important in The Gaia Hypothesis and _global warm studies_. I wrote to the author, and he sent me the source code in Basic. The difficulty is that no Basic compiler available can build the thing. Lisp is not a popular language by any means. However, there are many impressive Lisp applications. Here is a short list: 1 -- ACL2 -- a system developed by Boyer and Moore to prove the correction of hardware and applications. It is one of the most impressive programs that I know: [http://www.cs.utexas.edu/users/moore/acl2](http://www.cs.utexas.edu/users/moore/acl2)/ 2 -- Maxima, Computer Algebra System: [http://maxima.sourceforge.net](http://maxima.sourceforge.net)/ 3 -- PTC Creo CAD/CAM allows you to design and manufacture from clothes and shoes to complex machines. It seems that the Jarvis butler in the film Iron Man was inspired on PTC. My students have a complimentary copy of PTC and, believe me, the thing is amazing, specially the programs in Lisp. Here is a link: [https://www.ptc.com/en/products/cad/creo](https://www.ptc.com/en/products/cad/creo) 4 -- PVS. You probably saw PVS in the film The Marcian. Yes, that strange language that appears in the film is Lisp, doped with an overdose of macros: [https://imgur.com/NMPu7RT](https://imgur.com/NMPu7RT)/ [https://github.com/nasa/pvslib/blob/master/power/exponentiation_aux.prf](https://github.com/nasa/pvslib/blob/master/power/exponentiation_aux.prf) 5 -- Cyc is probably the most accomplished Artificial Intelligence program ever: [https://www.cyc.com](https://www.cyc.com)/ The list could go on and on, Mirai, Orbitz, Robot Motion Grammar, Biobike, Grammarly, Scream, Dendral, ... How could Lisp programmers write such beautiful pieces of software? I have a theory: They had time. Simple as that, they have time. Lisp programmers took years to create Cyc and Maxima. Such a lengthy effort was possible because Lisp does not change with time. You can still use the very Lisp programs that Svyatoslav Lavrov and Rifat Appazov used to launch artificial satellites and interplanetary probes. What about Nim? I believe that Lisp does not become obsolete due to its high content of Mathematics. As you probably noticed, Mathematics does not change either. When I was a student at Cornell, my professor of Mathematics used a book written by Gauss, and except for being written in Latin, the book was by no means obsolete. Mathematics is optimized, it has a minimum of entities. Optimization is minimizing or maximizing a utility function. Lisp grammar is the smallest possible, therefore you cannot change it. Any change would make it larger, which is against the principles that govern Lisp evolution. I hope that Nim finds a guiding principle that keeps it backward compatible with the work of the generations of programmers that will keep science moving.
