In the very first sentence, with the usage of "Feynman bros", we understand that it is not a text honestly discussing the limits and failures of Feynman (which would not be very interesting anyway), but a politically motivatedl attack against a man seen as too famous and influential.
He was very serious about his physics and wrote that stuff down.
Someone else wrote down his stories. His stories were probably often not entirely accurate, and whomever wrote down his stories also probably had an agenda. So books "by feynman" should be treated with some caution since they're written not by feynman.
His physics and science are obviously not "a sham". It is in fact possible for someone to be great and awful at the same time.
There is just a big market for "X great person of the past was actually awful" and "what you learned in school is actually a conspiracy". That these things get spread like wildfire whenever they are brought up, because some people thinks it make them seem smarter I assume. They also drop all introspection or skepticism about it. I would put "Feynman is actually awful" in the same bucket as the "Mercator project is a racist conspiracy" (No one owns a globe apparently) or the multitude of "actually x woman is responsible for scientific advancement, not the man" stories that get spread around. They all fail at any real analysis.
For epubs, I split the book into chapters and run ebook-convert on each chapter individually, adding an extra page if needed to make the number of pages even. Then I combine all the chapters and do a custom scheme for numbering (because you don't want numbers on blank pages, you want the numbering to start at chapter 1, etc)
For html books from Project Gutenberg for example, I make sure they have text in <p> and chapters in <h2>. Then do a similar logic with ebook-convert.
For pdf books, I just use pdf-lib to draw the pages directly.
I also shift odd pages to the right and even pages to the left so there is a larger inner margin than outer margin.
If you're looking to do custom books, I would just use ebook-convert by itself, it just won't be quite as pretty though because it lacks those improvements.
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