In fact, just the part on Satisfiability was previously published (2015, before Volume 4B published 2023) as "Volume 4, Fascicle 6: Satisfiability", and the eve

In fact, just the part on Satisfiability was previously published (2015, before Volume 4B published 2023) as "Volume 4, Fascicle 6: Satisfiability", and the even-earlier draft (pre-fascicle) is available online at https://cs.stanford.edu/~knuth/fasc6a.ps.gz https://cs.stanford.edu/~knuth/fasc6a.ps.gz In typical Knuth style, it is a very clear and solid explanation of the whole area, assuming no additional background than the rest of the book (high-school/undergraduate math), written in a lively style with concrete examples and humour. It also has the typical Knuth problems: everything is passed through Knuth's own notation and ideas (which are often clearer than mainstream, but nevertheless are different); it's all very densely written (every word matters, even in what looks like casual/breezy sentences): not skimmable, you have to read everything.