Bad foundations: code in Maxima (2026)

The preprint is called "Bad Foundations and Manipulable objects". You can read it here. This page is about its code in Maxima.

1. Change of variables

One of the things that I showed in my presentation at the World Logic Day 2026 - starting at 29:21, on slide 25 - was that Integration by substitution is a formula that is many levels of abstraction above its particular cases that we can visualize... and the best way to understand it is to start at at lower left part of the figure below and go to the upper right.

That figure looks like it was LaTeXed by someone lazy, incompetent, or without taste - like: why not `\begin{array}{rcl}'? Why did they omit the extra spacing between certain lines? - but then there's this:

Its LaTeX code was generated by Maxima!!! And its displayed version is readable! It uses many tricks from Edrxbox:

• it uses underbraces,
• it uses antideriv,
• some of the underbraced parts include the `dx's and `du's of the integrals,
• it displays the functions fp and gp as f' and g' - see here.