The Art of Computer Programming by Donald E. Knuth
www-cs-faculty.stanford.edu
www-cs-faculty.stanford.edu
From a previous preprint titled "Claude’s Cycle", dated 2026-02-28 [2]:
It seems that I’ll have to revise my opinions about “generative AI” one of these days. What a joy it is to learn not only that my conjecture has a nice solution but also to celebrate this dramatic advance in automatic deduction and creative problem solving. I’ll try to tell the story briefly in this note.
[2] https://www-cs-faculty.stanford.edu/~knuth/papers/claude-cyc...
Very interesting that he seems to be in the camp of “It’s ok if the machines prove it as long as we can understand and formally verify it after.”
Also: "Please do not tell me about errors that you find in an eBook, whether it's PDF or not, unless the same errors are present in a printed copy; such mistakes should be reported directly to the publisher."
Glad he thought to mention this, but I suspect his inbox will still be inundated.
https://www-cs-faculty.stanford.edu/~knuth/boss.html
(usually, I do find errors in books, esp. e-books, which reminds me, I need to pick up the corrected 3rd printing of _The Fall of Arthur_ by J.R.R. Tolkien before I read it again, since that should have the error I found corrected).
In any case, someone beyond the publisher will still get inundated with corrections about the PDFs and likely will demand their reward for it.
Amusingly in my first job in the 90s they still assigned each desk a labeled inbox and an outbox (two trays on the desk), but by then it was all email already so nobody ever used those on my desk. But they sat there for a few years as a memento to the 80s!
> And after Volumes 1--5 are done, God willing, I plan to publish Volume 6 (the theory of context-free languages) and Volume 7 (Compiler techniques), but only if the things I want to say about those topics are still relevant and still haven't been said. Volumes 1--5 represent the central core of computer programming for sequential machines; the subjects of Volumes 6 and 7 are important but more specialized.
> Syntactic Algorithms, in preparation.
9. Lexical scanning (includes also string search and data compression)
10. Parsing techniques
Now, half a century later, he is chickening out...
[0]: https://www.americanscientist.org/article/100-or-so-books-th...
given the timespan and the focus on complete analysis of running times and not just asymptotics, in the end maybe it wasn't so terrible a choice.
And unfortunately, for a lot of modern algorithms, you're going to have dive into SIMD-like algorithms, something MMIX doesn't have. Also, a lot of modern processors have a decent suite of bitwise operations (e.g., count leading/trailing zeros/ones, popcount) that is also missing from MMIX.
The programming languages that are in favor may change from decade to decade, but so to does most of the assembly language techniques.
They were all the rage for a while, because they make procedure calls fast but turn out to have subtle issues in highly-multithreaded scenarios.
Don's first computer was the IBM 650 https://en.wikipedia.org/wiki/IBM_650?useskin=vector see also http://ed-thelen.org/comp-hist/KnuthIBM650Appreciation.pdf so MIX was a simplified version of the 650 because, well, it's well-defined and simple -- and Don knew a popular IBM machine very well. And there's this, in Vol 1:
This series of books is affectionately dedicated to the Type 650 computer once installed at Case Institute of Technology, in remembrance of many pleasant evenings.
MMIX is for all you youngsters who think RISC is all the rage ;-) and I think he does an admirable job creating a fully-defined machine that does use more modern hardware techniques. The fact that he fully defines his underlying machine is exactly correct, because it lays the foundation for precisely expressing the algorithms, and for giving Time and Space (runtime) estimates.
I believe it's fundamentally incorrect to think of these abstract machines as 'assembly language' but rather, I think, they define a stable foundation onto which accurately described algorithms can be expressed. You're supposed to 'play computer' and follow along -- step by step -- to understand the deep details of the algorithms.
(There's another criticism to level at pseudo-assembly language, which is that modern high-performance processors are superscalar with cache hierarchies, which makes the analysis of execution time itself difficult from the kind of first principles that Knuth is working at. I can appreciate why Knuth is working differently from the more traditional big-O notation of typical algorithms classes, but it does need to be acknowledged that it does sap the treatise of its supposedly timeless quality.)
I think, tho, the fundamental reason is: he specs the machine. It does exactly what he says it does. No edge cases, no surprising behavior that LLVM IR or WASM might have; also, I'm sure he spec'd it to make the algorithms he implements elegant or at least more understandable.
I suspect part our views comes from the purity of Mathematics (Knuth) and the actuality of Computer Science. I'm even sympathetic to your view, because then we could verbatim copy Knuth's algos to WASM etc and run them, and we get a twofer: a deeper understanding of the algo AND a deeper understanding of the underlying V-ISA (PTX, BEAM, WASM, LLVM IR, etc).
I think the learning / understanding of the algos Knuth presents partially comes from us Playing Computer, and manually going through the code. It's that pedagogy comes first, I think.
Next time I run into Don, I'll ask him about this. 'cause you're also correct about L1...Ln caches affecting performance drastically.
(And, yes, I had wondered why Don did MMIX he didn't create a "RISC-V" before there was a RISC-V; that is, why didn't he create the Next Great RISC Machine? He said he talked with John Hennessy and Richard Sites. This was in 1990.)
Here's HN on RISC-V vs MMIX: https://news.ycombinator.com/item?id=14635361
Pascal is simple and clear, and can be translated easily to anything from LISP, Fortran, Python to C or C++ (in fact, subsets of Pascal are often used as sample language in books about compilers, including in Pascal inventor N. Wirth's own compiler book (which, unlike Knuth's, was completed timely):
Wirth, Niklaus, Compilers (1996), 101pp., 2rd revision, 2017, online: https://people.inf.ethz.ch/wirth/CompilerConstruction/Compil..., last accessed 2026-07-07).
It does not matter that Pascal is not much in use anymore, because due to its readability, it's timeless. It nearly reads like English prose, yet is automatically executable. It has also been standardized, and there is a book-sized language description available, as are several -- commercial and open source -- implementations.
In contrast, his pseudo-assembler is arcane. Whenever I wanted to implement an algorithm following Knuth TACOP, I had to work off his English pseudo-code description rather than the associated pseudo-assembler code.
So no, it’s not a blunder by DEK to avoid abstracting the complexity into higher-level languages, nor to have not written it as a handbook. TAoCP is not a handbook-like book, it is well beyond that. There are plenty of books for that. For that purposes, you might consider consulting CLRS or Skiena instead.
Obviously I know I can probably find them on the high seas.
> The authorized PDF versions can be purchased at www.informit.com/taocp
Educational books are an investment in the future, and some (like Euclid's Elements) don't ever lose their relevance.
- i could buy a laptop at the price of the books being sold here. it is just tooo much.
- the author needs to take PPP into account and price accordingly similar to how steam does it
- i could get a really good meal for 500 rs at a good restaurant here
- the cost of the book is close to 80 such meals
- if we price it in your currency assuming 100$ for a really decent meal, the author is charging 8000$ for the books