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Dubious Math in Infinite Jest (2009)

by rafaepta on 6/10/25, 3:04 PM with 118 comments

• by npilk on 6/10/25, 3:27 PM

  I've seen a theory that the mistakes Pemulis makes are intentional, and signal that he isn't as smart as he thinks and that he doesn't really have everything in control.

  I'm not sure; clearly DFW had some math aptitude but these also could have been honest mistakes. Presumably it would have been harder for editors to check these things in the 90s.

  The probability error seems harder to explain and likely just a mistake.

  Edit - While searching a bit more about this, I found an interesting perspective on a message board:

  > The main thing that I think argues for Pemulis not being as smart as he thinks he is, is that he is the analogue of Polonious from Hamlet. In Hamlet, the court jester (the "fool") is actually really wise and always speaks the truth (=Mario), while the King's supposedly "wise" counselor, Polonious, actually gets everything wrong.

  I find that pretty compelling. I hadn't really thought about deeper correspondences with Hamlet beyond Hal and his parents.

  https://infinitesummer.org/forums/viewtopic.php?f=12&t=471

• by A_D_E_P_T on 6/10/25, 4:28 PM

  DFW also wrote Everything and More: A Compact History of Infinity -- an uncritical review of Cantor's work, which was absolutely loaded with errors.

  Rudy Rucker wrote a scathing review here: https://www.rudyrucker.com/oldhomepage/wallace_review.pdf

  I actually read Everything and More and it's probably even worse than that. Though I'll admit that I'm a little bit biased; I'm a sort of Aristotelian Realist or even a Finitist when it comes to mathematics, and I view Cantor's hierarchy of infinities as... well... schizo at best.

• by arh68 on 6/10/25, 3:52 PM

  Maybe he "just" got it wrong. Maybe they're typos, and the manuscript was correct. Or...

  Maybe Pemulis gave Hal an obviously wrong derivative, and when uncorrected, drove Pemulis to abruptly end the tutoring. Maybe Pemulis said it right but Hal heard it wrong. Or...

  Maybe it's "just" another sign they're in an alternate universe where even the math is different. That's pretty much how I feel about it

• by lou1306 on 6/10/25, 3:15 PM

  > the Mean Value Theorem for integrals is a theoretical tool for proving the existence of this particular x'. It does not, however, offer any method of finding the value of x'. Therefore, it is difficult to imagine how the Mean Value Theorem for integrals could be employed in Pemulis' Eschaton calculations.

  Knowing the character, at least this one could be explained as yet another parlour trick from Michael Pemulis. God knows how he actually calculated those values.

• by andy_xor_andrew on 6/10/25, 3:32 PM

  > Again, Mike Pemulis is lecturing Hal, but this time he is helping Hal prepare for the college board exams. Pemulis states that for the function x^n, the derivative is nx + x^(n-1). In fact, the correct expression is nx^(n-1). This, too, may be a typographical error.

  Another possibility is that Pemulis is simply bad at math :D

• by FL33TW00D on 6/10/25, 3:27 PM

  I look forward to the day another book makes me feel like IJ - even with the mathematical flaws :)

• by nneonneo on 6/11/25, 6:53 AM

  Mathematically, the odds of getting exactly N heads after flipping a fair coin 2N times is surprisingly high - it asymptotically approaches 1/sqrt(pi * N) as N becomes large. For the problem in IJ, this comes out to 1/(3.14 * 54) which is 0.076776 - not far from the exact value of 0.076599. As another example, if you flip a fair coin 1000 times, you’ll get exactly 500 heads about 2.5% of the time.

  The proof is also similarly easy: it’s a straightforward application of Stirling’s approximation to the formula (2N!)/(N!*N!)/2^(2N).

• by neuroelectron on 6/10/25, 9:03 PM

  Has anyone actually read Infinite Jest in its entirety? I got about 50 pages in and I'm pretty sure I got the jist of it from that. The constant slog into minutia and clunky grammar made it very slow reading for me. There were some funny parts but overall the effort didn't feel worth it.

  I tore through Gravity's Rainbow (mentioned in another thread).

• by trefoiled on 6/10/25, 4:21 PM

  This isn't the only example of a debate over intentionality in mistakes in Infinite Jest. The book's french is also littered with errors so egregious that most think they could only have been intentional [1].

  [1] https://ask.metafilter.com/116066/French-language-in-Infinit...

• by NewsaHackO on 6/10/25, 4:13 PM

  I haven’t read IJ in a while, but I don’t think I agree with the first one. Unless he specifically said that each player has an equal chance of winning, I would not assume that to be the case.

• by thaumasiotes on 6/10/25, 3:19 PM

  > Intentional math errors in David Foster Wallace's work

  The actual title of this piece is "Dubious Math in Infinite Jest". There is no suggestion, in the title or the contents, that the errors are intentional. In the author's words:

  > As I have said, I have no theories to explain the existence of these errors.

• by ProllyInfamous on 6/10/25, 11:07 PM

  David Foster Wallace & David Sedaris are both "consummable media" in that they're pleasurable to read... but you walk away from their material and just feel empty (except for esoteric connections you might've woven into your own storyline). With any expert technical knowledge, you'll quickly know that Wallace wasn't any expert.

  I've only read Infinite Jest once, and would have edited it differently myself — but the scenes on addiction are powerful, stressful, and accurate (as somebody over a decade california clean). Pale King is better prose, but in both cases DFW isn't a "complete" author — he expects too much from his readers.

  At least in Sedaris' case, he keeps his prose brief =D