These are friendly criticisms of issues I found while translating David Deutsch’s book The Beginning of Infinity and afterwards, since 2019. The issues range from tiny to notable. It's my favorite book.

All comments about language should be taken with a grain of salt as I’m not a native speaker of English.

Familiarity with the book will definitely help but is not necessary.

Here are my main referenced works:

• Deutsch, David. 2012. The Beginning of Infinity: Explanations That Transform the World. New York: Penguin Press. (‘BoI’; I also frequently quote from the ebook based on the same edition, so I can’t always give page numbers.)
• Popper, Karl. 1983. Objective Knowledge: An Evolutionary Approach. Oxford: Oxford Clarendon Press. (‘OK’)
• Popper, Karl. 2002. Conjectures and Refutations. London, New York: Routledge. (‘C&R’)

Potential errors

In no particular order:

• Chapter 3:

  (See, for instance, the historian Jenny Uglow’s book Lunar Men.)

  Jenny Uglow’s book is called The Lunar Men, not “Lunar Men”. The bibliography has the correct title:

  Jenny Uglow, The Lunar Men (Faber, 2002)

  I was originally acknowledged for finding this error on the BoI errata page but that erratum was lost when the website was replaced and it hasn’t been re-added since.

• Chapter 17:

  In his book Guns, Germs and Steel, the biogeographer Jared Diamond […].

  and

  Diamond says that his main reason for writing Guns, Germs and Steel was […].

  Diamond’s book is called Guns, Germs, and Steel, not “Guns, Germs and Steel” (there’s a comma missing after “Germs”). It's not listed in the bibliography (even though Deutsch comments on it more than on Uglow's book).

• Chapter 1:

  So much for inductivism. And since inductivism is false, empiricism must be as well. For if one cannot derive predictions from experience, one certainly cannot derive explanations.

  The symmetry between the last two sentences suggests that inductivism is about deriving predictions from experience. But in the glossary for ch. 1, it says, in the entry on inductivism:

  The misconception that scientific theories are obtained by generalizing or extrapolating repeated experiences, […]. [Emphasis added]

  So which is it? Is inductivism about deriving new predictions or new scientific theories?

• Ch. 16 first speaks of one extraterrestrial observer of an early human civilization:

  In prehistoric times it would not have been obvious to a casual observer (say, an explorer from an extraterrestrial civilization) that humans were capable of creative thought at all.

  Later on in the same chapter, it’s multiple extraterrestrials, even though it’s a reference to the single observer from above:

  From the perspective of those hypothetical extraterrestrials observing our ancestors, […].

  May be better to make it consistently one or multiple observers.

• Chapter 9:

  In 1798, Malthus had argued, in his influential essay On Population, […].

  That essay may be called An Essay on the Principle of Population: https://www.google.com/books/edition/An_Essay_on_the_Principle_of_Population/38JJAQAAMAAJ A search online doesn’t turn up any essay called just “On Population”. For example, none of the works listed on Malthus’ Wikipedia article is called that. The Wikipedia article on the book itself says “Essay on Population” one time, which seems to be shorthand, but that’s after the full title is mentioned. People use different shorthands for it, e.g. Darwin is quoted in that same article as saying “I happened to read for amusement Malthus on Population” (the given source is “Barlow, Nora 1958. The autobiography of Charles Darwin. p. 128”) and Alfred Russel Wallace as saying “perhaps the most important book I read was Malthus’s Principles of Population […]” (source “Wallace, Alfred Russel 1908. My life: a record of events and opinions”). Shorthand works but then the bibliography should have an entry mapping the shorthand to the full title. The bibliography in BoI does not list Malthus’ book.

• Chapter 11:

  [P]erhaps the story could propose some novel analogue of communication which, like quantum inference, did not involve sending messages.

  That says “quantum inference” but I suspect it should say ‘quantum interference’. Quantum interference is a concept mentioned several times in that chapter and also listed in that chapter’s glossary. The word ‘inference’, on the other hand, is only mentioned that one time (in that chapter), so I’m fairly confident it’s a typo.

• Chapter 11:

  Hence it is not the case that all the atoms on the surface of the planet are changed by the arrival of the radio message.

  The message is transmitted by laser, not radio (this resulted in an acknowledgment: https://www.thebeginningofinfinity.com/book/errata/#274)

• The diagram in chapter 8 on p. 173 displaying Infinity Hotel’s waste-disposal system says “Step 1” three times, whereas (presumably) it should say ‘Step 1’, ‘Step 2’, ‘Step 3’.

• Same diagram, our copy editor Malte Heidemann noticed that it should speak of minutes instead of seconds (since the surrounding text is about minutes)

• Chapter 3:

  [A]n unproblematic state is a state without creative thought. Its other name is death.

  Plants do not have creative thought, yet they are alive. Also, consider other states without creative thought – deep sleep, for instance, or a coma – which are problematic because you're defenseless, others may not know whether or when you'll wake up, and so on. To be sure, the quote leaves room for that – it doesn't say every state without creative thought is death – but the reader can easily miss that.

  While the sentiment of the sentence is true – if we stop solving problems, we eventually die; utopia is neither desirable nor achievable – it seems to be factually false.

  In addition, the phrase "unproblematic state" is a bit ambiguous. It can either mean 'there's nothing wrong with that state' or 'a state in which you have no problems'. Deutsch intends the latter meaning to refute the former (i.e., there'd be something very wrong with not having any problems) while (implicitly) using the same word for both, which can be confusing. Perhaps it would be better to say 'A state without problems...' – that makes it clear that the intended meaning is the latter one. Incidentally, it makes the sentence more symmetric, so it ends up sounding better: 'A state without problems is a state without creative thought.'

• Chapter 1 says conflicting things about the explanatory nature (or lack thereof) of rules of thumb:

  It also makes sense to speak of the reach of non-explanatory forms of knowledge – rules of thumb, […].

  This quote states that rules of thumb are non-explanatory, meaning they have no explanatory content. Then, in the glossary of the same chapter:

  Rule of thumb[:] ‘Purely predictive theory’ (theory whose explanatory content is all background knowledge).

  This quote, on the other hand, states that rules of thumb do have explanatory content.

• Chapter 11, paragraph starting with: “In principle, a phenomenon could appear unpredictable to observers for one or more of three reasons.” Does the halting problem fall under one of the three mentioned reasons? If not, it may be worth adding a fourth.

• Chapter 3 summary says

  Apart from the thoughts of people, the only process known to be capable of creating knowledge is biological evolution.

  Not sure that’s true. I think meme evolution creates knowledge too, even among some animals. For example, there are the ape memes in ch. 16. Deutsch later agreed, but he disagreed about it being a future erratum because he would not have considered this a mistake at the time of writing. (But how? The discussion of memes in chapters 4, 15, and 16 rests on meme evolution creating knowledge.)

• Related issue: chapter 4 says

  In this case, the upshot is that what science – and creative thought in general – achieves is unpredictable creation ex nihilo. So does biological evolution. No other process does.

  But meme evolution does, too, and meme evolution is not only scientific and can occur between non-creative beings.

• Ch. 4 says:

  [T]here is no relevant difference between (1) ‘the same’ laws of physics with different constants and (2) different laws of physics.

  Why not? IIUC that the laws of physics can be expressed as functions in the sense of the lambda calculus, there seems to be a big difference between (1) ‘the same’ functions with different constants and (2) different functions. For example, consider:

  a) Calculating the radius of a circle using the circumference and pi = 3.14…
  b) Calculating the radius of a circle using the exact same function but with pi = 6, say.

  vs

  a) Calculating the radius of a circle using the circumference and pi = 3.14…
  d) Calculating the sum of two numbers

  The former two have the same structure and purpose, whereas the latter two have a completely different structure and purpose – so there is a "relevant difference" between them. (I know laws of physics aren’t about circles or addition but I don’t know how to write laws of physics as functions so I had to use something else to illustrate my point.)

• Chapter 15:

  But our society (the West) is not a static society. It is the only known instance of a long-lived dynamic (rapidly changing) society.

  In short: the West is a dynamic society. This claim seems to contradict what Deutsch later says about the West being in a transition period toward a dynamic society. Ch. 15 summary:

  Western civilization is in an unstable transitional period between stable, static societies consisting of anti-rational memes and a stable dynamic society consisting of rational memes.

  Granted, there’s no comma between “stable” and “dynamic”, leaving room for Western society being an unstable dynamic one. It would take more research.

• Chapter 10 (Socrates speaking, explaining a thought experiment to Hermes):

  If the Spartan Socrates is right that Athens is trapped in falsehoods but Sparta is not, then Sparta, being unchanging, must already be perfect, and hence right about everything else too. Yet in fact they know almost nothing.

  Sparta is used as an example of a static society, and how static societies are not, in fact, perfect. It's the perfection that Socrates deems controversial, not whether Sparta is unchanging (he says he thinks it really is unchanging: "Sparta, being unchanging"). But later, in the chapter on static societies (ch. 15), Deutsch writes that static societies are not unchanging:

  Static societies, by this definition, are not perfectly unchanging. They are static on the timescale that humans can notice; but memes cannot prevent changes that are slower than that. So meme evolution still occurs in static societies, but too slowly for most members of the society to notice, most of the time.

  Therefore, the argument about how Sparta would need to be perfect already (yet obviously isn't) can’t be true – I agree with the conclusion (Sparta was not perfect), just not with how Socrates gets there. And while the passage containing the thought experiment gives the reader the impression that Sparta cannot be perfect (true), it suggests that it is unchanging nonetheless (false, and conflicting with ch. 15).

  Could it be a misunderstanding between Hermes and Socrates? Hermes first says:

  [S]ince one of [the Spartans'] ‘ways’ is to preserve all their ways unchanged, [...] –

  He suggests that Spartans try to avoid change. That in itself doesn't mean they manage that – so far so good; it's still compatible with ch. 15. Then Socrates says:

  Then the Spartans must also have been right ever since they embarked on their present way of life. The gods must have revealed the perfect way of life to them at the outset.

  It's logically possible for Sparta to be wrong at the outset (about something other than not wanting to change), then change (in that one regard in which they are wrong, unwillingly, and maybe without noticing), and only then be perfect. (It's not epistemologically possible, but that's a different argument.)

  What Deutsch wants to do here is persuade the reader that static societies are bad; that the pursuit of stasis is not worthwhile. He has Socrates and Hermes present that argument for him. The reader will agree that it's ridiculous to think Sparta was perfect from the outset – thereby invoking its unchanging character as something that isn't controversial, but needed for the argument. Also, Deutsch doesn't have Hermes correct Socrates on this point – even though Hermes does correct Socrates on something else, so it does matter to Deutsch to have Hermes correct Socrates' errors. Therefore, I don't think it's a misunderstanding between Socrates and Hermes, it's actually just a mistake.

• Chapter 1 glossary says explanations are “[s]tatement[s] about what is there, what it does, and how and why”. But I believe explanations are more than that – e.g. we can explain fiction, counterfactuals, and history. I wrote a blog post on this topic.

• Two potential errors in chapter 10, where it says:

  Sprinting eagerly ahead of the rest is the teenage poet Aristocles, whom his friends call PLATO (‘the Broad’) because of his wrestler’s build.

  There seem to be some debates around whether Plato was really called Plato for his wrestler’s build, and even whether his given name was really Aristocles. See this article (in English) and this article (in German). It would take more research though.¹

Missing sources and misquotes

• Throughout: some quotes are missing sources altogether (e.g. the Edison quote about inspiration vs perspiration, the Feynman quote about learning not to fool oneself), the rest have only partial source information. Every quote should have complete source information, including page number, year of publication, and place of publication. (I realize it’s ironic I’m not giving page numbers for many BoI quotes in this article – again it’s because I’m mostly using the ebook which makes searching, and also checking for misquotes, a lot easier.)

• Throughout: misquotes. I noticed them when our copy editor recommended adding more sources. As I looked for and found some of the sources, I also noticed some misquotes when comparing quotes to the originals. Around the same time, Elliot Temple also discovered misquotes independently – when I did a literal search for one of the misquotes online, a post by Temple came up. Regarding that and a related post:

  1. Someone claims Deutsch “doesn’t give credit to Quine for his reality of abstractions idea”: Deutsch told me he hasn’t read Quine

  2. Regarding the term ‘Machiavellian hypothesis’: it’s not meant to be a literal quote. The English BoI uses single quotation marks for literal quotes, imaginary quotes, scare quotes, and to denote terms, so that can lead to confusion. Deutsch told me that it’s the publisher’s house style. (Though arguably the confusion would be cleared up if every literal quote were accompanied by a source. In the translation, we made a point of using double quotation marks only for literal quotes and single quotation marks for everything else, plus I added a bunch of sources.) And Deutsch wrote to me re ‘Machiavellian hypothesis’:

     Single quotes is correct. Blackmore didn’t invent the theory that this is why intelligence evolved:

     https://books.google.com/ngrams/graph?content=Machiavellian+hypothesis&year_start=1800&year_end=2019&corpus=26&smoothing=3&direct_url=t1%3B%2CMachiavellian%20hypothesis%3B%2Cc0#t1%3B%2CMachiavellian%20hypothesis%3B%2Cc0

     https://dictionary.apa.org/machiavellian-hypothesis

     And he followed up:

     That is to say, 'Machiavellian hypothesis' is the correct term, and single quotes is correct for it.

• I’ve noticed a misquote of Pericles. In BoI ch. 9, it says:

  Instead of looking upon discussion as a stumbling-block in the way of action, we think it an indispensable preliminary to any wise action at all.

  Italics mine. No source is given, but in the one Deutsch gave me and said he had used (https://www.gutenberg.org/cache/epub/7142/pg7142.txt), it says:

  [I]nstead of looking on discussion […].

  Italics again mine. Note also that the brackets at the beginning around the letter ‘I’ are necessary because the quote starts in the middle of a much longer sentence and hence that letter is originally lowercase. The entire sentence from the source reads (I am preserving the line breaks from the source):

  Our public men have, besides
  politics, their private affairs to attend to, and our ordinary
  citizens, though occupied with the pursuits of industry, are still fair
  judges of public matters; for, unlike any other nation, regarding him
  who takes no part in these duties not as unambitious but as useless, we
  Athenians are able to judge at all events if we cannot originate, and,
  instead of looking on discussion as a stumbling-block in the way of
  action, we think it an indispensable preliminary to any wise action at
  all.

  So the quote in BoI is only the last three lines of that long passage.

• There’s also a misquote of Dawkins in ch. 3 of BoI:

  I believe that an orderly universe, one indifferent to human preoccupations, in which everything has an explanation even if we still have a long way to go before we find it, is a more beautiful, more wonderful place than a universe tricked out with capricious ad hoc magic.

  I first noticed that something was off about this quote when I saw that there was no hyphen between the words "ad" and "hoc" at the end. They both describe the noun “magic”, so there should normally be a hyphen. I decided to check the original, which you can find in the Amazon preview here towards the bottom of p. xi. Amazon lists the year 2000 on the product page but inside the book it says 1998, which is the year given in BoI, so I think it's the same edition Deutsch used. The passage says:

  I believe that an orderly universe, one indifferent to human preoccupations, in which everything has an explanation even if we still have a long way to go before we find it, is a more beautiful, more wonderful place than a universe tricked out with capricious, ad hoc magic.

  There, you can see that those two words are italicized (signifying a foreign language, Latin) – “ad hoc” – and as such it’s a grouping which is arguably separate enough from the word “magic” that no hyphen is necessary or even proper. Also note that the original has a comma after “capricious”. The misquote is repeated two paragraphs further down. Once those two mistakes are fixed, the quotes are the same – one way to check that is to check programmatically, e.g. using JavaScript:

  'I believe that an orderly universe, one indifferent to human preoccupations, in which everything has an explanation even if we still have a long way to go before we find it, is a more beautiful, more wonderful place than a universe tricked out with capricious, *ad hoc* magic.' === 'I believe that an orderly universe, one indifferent to human preoccupations, in which everything has an explanation even if we still have a long way to go before we find it, is a more beautiful, more wonderful place than a universe tricked out with capricious, *ad hoc* magic.'
  // => true
  

  Programmatic checks are basically ~100% reliable (if you use them right) because computers are really good at comparing strings. Another easy programmatic check is just copying a text and then pasting it into an ebook's or browser's word search. For example, if you paste the full Pericles quote above (the one spanning multiple lines) into a word search (cmd + f on mac) while on the source page, the browser will highlight the corresponding passage. That means every single character is the exact same. (Caution when using italics and ellipses, you may not notice missing or superfluous italics, and the quote may not match due to ellipses but still be correct!)

Missing credit

The following are instances of what I believe to be accidentally missing credit, not any malicious plagiarism.

• The concept of background knowledge (ch. 1):

  Knowledge that is both familiar and uncontroversial is background knowledge. A predictive theory whose explanatory content consists only of background knowledge is a rule of thumb.

  Popper uses this same term (‘background knowledge’) with the same meaning many times, for example in C&R p. 334:

  This need is a result of the growth of knowledge—of the incorporation of what was new and problematic knowledge into background knowledge, with a consequent loss of explanatory power to our theories.

  The loss of explanatory content when going to what Deutsch calls a ‘rule of thumb’ is captured by this quote, too.

  From C&R p. 524:

  Let […] b [be] the ‘background knowledge’, that is to say, all those things which we accept (tentatively) as unproblematic while we are testing the theory.

  Again from C&R (I don’t have a page number handy for this quote but both https://www2.gwu.edu/~clade/bisc%20207/farris_2008.pdf and https://static.hlt.bme.hu/semantics/external/pages/naturalista_hiba/en.wikipedia.org/wiki/Falsifiability.html (same ISBN as my source) attribute it to page 238) – I take the italics from the first source as canon (the second source lacks them):

  While discussing a problem we always accept (if only temporarily) all kinds of things as unproblematic: they constitute for the time being, and for the discussion of this particular problem, what I call our background knowledge.

  In this last quote, Popper says he came up with the term 'background knowledge' (“I call”).

• Chapter 1:

  Before there was science there were rules of thumb, and explanatory assumptions, and myths. So there was plenty of raw material for criticism, conjecture and experiment to work with. Before that, there were our inborn assumptions and expectations: we are born with ideas, and with the ability to make progress by changing them.

  That’s Popper.
  First, Popper on myths in C&R p. 169:

  The peculiar thing which we call scientific tradition has often been discussed. People have often wondered about this queer thing that happened somehow somewhere in Greece in the sixth and fifth centuries before Christ—the invention of a rational philosophy. [...]
  The early Greek philosophers did indeed try to understand what happened in nature. But so did the more primitive myth-makers before them. […] To put it crudely, the pre-scientific myth-makers said, when they saw a thunderstorm approaching: ‘Oh yes, Zeus is angry.’

  On the next page:

  [I]nstead of merely handing on a tradition, [the early Greeks] challenged it, and sometimes even invented a new myth in place of the old one.

  And, a bit further down:

  [T]he Greek philosophers invented a new tradition—the tradition of adopting a critical attitude towards the myths, the tradition of discussing them; the tradition of not only telling a myth, but also of being challenged by the man to whom it is told.

  These quotes also show that Deutsch got the idea of a tradition of criticism, which he uses many times in BoI, from Popper (Deutsch has read C&R). The first instance is in BoI ch. 1:

  What was needed for the sustained, rapid growth of knowledge was a tradition of criticism. Before the Enlightenment, that was a very rare sort of tradition: usually the whole point of a tradition was to keep things the same.

  Compare this once more to what Popper wrote above: "[...] Greek philosophers invented a new tradition—the tradition of adopting a critical attitude towards the myths, [...]." In other words, they invented a tradition of criticism.

  Popper also wrote, C&R p. 174:

  [Y]ou need two beginnings for science: new myths, and a new tradition of changing them critically.

  Second, Popper on inborn knowledge, in C&R p. 36:

  [B]y far the most important source of our knowledge—apart from inborn knowledge—is tradition.

  And, in a parenthetical on the next page:

  […] ([A]ll men, like all other animals, and even all plants, possess inborn knowledge).

  Interestingly, Popper disagrees with Deutsch about inborn ideas in particular. C&R p. 62:

  The theory of inborn ideas is absurd, I think; but every organism has inborn reactions or responses; and among them, responses adapted to impending events. These responses we may describe as ‘expectations’ […].

  And, shortly thereafter:

  In view of the close relation between expectation and knowledge we may even speak in quite a reasonable sense of ‘inborn knowledge’.

  Recall that Deutsch instead writes "there were our inborn assumptions and expectations: we are born with ideas", essentially suggesting inborn assumptions and expectations are both a kind of inborn idea. So compared to Popper it's a bit of a fudge – Deutsch doesn't distinguish between expectations and ideas in the same way Popper does (though I disagree with Popper that speaking of inborn ideas is "absurd").

• Chapter 1: the role of observation being not that of producing theories but of eliminating them:

  Experience is indeed essential to science, but its role is different from that supposed by empiricism. It is not the source from which theories are derived. Its main use is to choose between theories that have already been guessed. […]
  However, that was not properly understood until the mid twentieth century with the work of the philosopher Karl Popper.

  Credit is given to Popper this time, but no source. One source could have been C&R p. 172:

  Scientific theories are not just the results of observation. They are, in the main, the products of myth-making and of tests. Tests proceed partly by way of observation, and observation is thus very important; but its function is not that of producing theories. It plays its role in rejecting, eliminating, and criticizing theories; and it challenges us to produce new myths, new theories which may stand up to these observational tests.

  (Arguably, when Popper says "[s]cientific theories are not just the results of observation" (emphasis added), he seems to grant that they can be – or else he would have said 'just not' or 'never'. This more permissive stance seems to contradict some of his other writings, where, I'm paraphrasing from memory, he said observation can never produce theories.)

• Chapter 2:

  Scientific truth consists of such correspondence between theories and physical reality.

  That sounds like a rewording of Alfred Tarski’s correspondence theory about the truth being correspondence to the facts, as referenced often by Popper, e.g. in C&R p. 36:

  (That we may operate, without getting involved in antinomies, with the idea of objective truth in the sense of correspondence to the facts, has been shown by the work of Alfred Tarski.)

  And (C&R p. 303):

  All this was changed by Tarski’s theory of truth and of the correspondence of a statement with the facts. Tarski’s greatest achievement, and the real significance of his theory for the philosophy of the empirical sciences lies, I believe, in the fact that he re-established a correspondence theory of absolute or objective truth which showed that we are free to use the intuitive idea of truth as correspondence with the facts.

  There are more passages in C&R about Tarski's correspondence theory. Tarski's name is not mentioned in BoI.

• Chapter 4:

  The fundamental error being made by Lamarck has the same logic as inductivism.

  That’s a notable discovery by Popper. I noticed this when I first read Popper's books (after reading BoI), and have since found at least one other person remarking on the missing credit online. The German translation now credits Popper and gives a German source (Popper’s translated autobiography): “Ausgangspunkte, 5. Auflage 2018, Piper, München, Übersetzer Friedrich Griese, S. 119” If someone has a quote handy from an English source, please leave a comment.

• Chapter 6 contains several paragraphs about something called the RNA-world hypothesis. It's a theory about earth's evolutionary history and the origin of life. It's not widely known among the general populace and reads as if Deutsch came up with it. It should be phrased in such a way that the reader knows it’s not his idea, and instead one which is known among biologists. (He suggested I mention the RNA-world hypothesis by name in my book because, IIRC, I accidentally attributed the theory to him in the second edition and he asked not to be credited.)

  Shortly before he presents the RNA-world hypothesis, he talks about how genes replicate. This passage is not problematic:

  Genes in present-day organisms replicate themselves by a complicated and very indirect chemical route. In most species they act as templates for forming stretches of a similar molecule, RNA. Those then act as programs which direct the synthesis of the body’s constituent chemicals, especially enzymes, which are catalysts. [...] Those catalysts in turn control all the chemical production and regulatory functions of an organism, and hence define the organism itself, crucially including a process that makes a copy of the DNA.

  This is more or less common knowledge – ~every middle schooler will know this from biology class. Even those don't know all the details generally know that genes replicate, and that this is roughly how they do it. So no credit is necessary. But then he ends the paragraph with:

  How that intricate mechanism evolved is not essential here, but for definiteness let me sketch one possibility.

  That last part – "let me sketch one possibility" – can (need not, but can) read as a cue that what follows is Deutsch's idea. Either way, it shows that Deutsch knows the reader probably isn't familiar with the RNA-world hypothesis. The passages that follow are too numerous to quote here, but RNA world is not mentioned by name (which would establish that it's something known). It's also less well known than genes' replication mechanism while being more controversial – not all biologists agree on RNA world, while most (AFAIK) agree on how genes replicate, at least broadly. Gene replication is a well-understood process, while the origin of life is still a mystery, making it even more of a possibility that this is Deutsch's own conjecture. The paragraphs 'sketching out' the RNA-world hypothesis never say 'some biologists think' or anything like that.

  A simple addition can avoid confusion here: 'Let me sketch one possibility known as the RNA-world hypothesis' – like Deutsch does with the Spaceship Earth metaphor in ch. 3 (see below). And then sprinkling in a few 'some biologists think' and 'it is said that' throughout those paragraphs can help remind the reader that this idea isn't Deutsch's.

• Chapter 6:

  The process of copying a genome is called a living organism.

  I'm not a biologist, but this doesn't sound right. Copying a genome has to be finished early in an organism's life or else it can't mature.

  Even if we consider the copying process not to be over until the next copy is made, many organisms usually live on after their genome is copied – i.e., after they've produced offspring. And when a single organism has multiple offspring, it's still just a single organism. So, whatever living organisms are, they are more than just the process of copying a genome.

• Chapter 10:

  And in future, by the same means – namely by refusing to hold any of our ideas immune from criticism – we may learn some matters not so light.

  The concept of immunity from criticism is Hans Albert’s. See, for example, the Wikipedia entry on Albert: “[…] Albert coined the phrase ‘immunity against criticism’”. See also the German Wikipedia’s dedicated entry on the concept, which entry credits Albert with introducing the concept into the philosophy of science. He has been credited in a footnote in the German translation so as not to disrupt the dialog in that chapter. The part “some matters not so light” is a Wilhelm Busch quote as translated from German into English by Popper, but if it’s meant as an easter egg it only works without a source and without quotation marks. Popper’s translation can be found in OK p. 55. The original source given there is “Wilhelm Busch, Schein und Sein, 1909”.

• ‘Spaceship Earth’ – when it’s first introduced in ch. 3, it’s phrased in such a way that it’s clear it’s not Deutsch’s idea:

  Another influential idea about the human condition is sometimes given the dramatic name Spaceship Earth.

  Still, it may be worth attributing it to Henry George (first known use of the term according to Wikipedia, https://en.wikipedia.org/wiki/Spaceship_Earth) and also Buckminster Fuller, who popularized the term (again Wikipedia), or one of the other people who popularized it.

• Two instances that would take more research:

  • Problems being conflicts between ideas (ch. 1) – isn’t that Popper?

  • The purpose of science being explanations of the world – an underlying theme of BoI – isn’t that Popper, too? In OK p. 191 he writes:

    I suggest that it is the aim of science to find satisfactory explanations, of whatever strikes us as being in need of explanation.

    Can’t recall credit being given to him for this.

Glitches (typos and other stuff)

The following are miscellaneous and smaller issues. I wrote them down over the years whenever I noticed them. I did some light editing and checking but there are so many that you should expect some inconsistencies and/or mistakes on my part (same for the next section about the index).

• BoI at beginning says Deutsch is a professor at Oxford, but he’s a visiting professor there. He made a point of that for the German edition so it seems relevant
• The entry “Fundamental or significant phenomenon” in the terminology section of ch. 3 is followed by a colon, whereas no other entry is
• Ch. 3: “[N]one of the endless stream of problems […]” should be 'streams' plural.
• Does the entry in the terminology section for fine-tuning in chapter 4 need to be surrounded by quotes?
• Bibliography: the third-to-last bibliography entry has the month in parentheses, but the last one says “winter” without parentheses. Should be consistent.
• If the quote is accurate, this is a glitch in FoR: in the quote from FoR in chapter 5, in the part that says “[…] the copper atom’s being there, you would still not be able to say ‘Ah yes, now I understand why they are there’”. It needs to be either plural genitive 'copper atoms’' or 'now I understand why it is there' not “they”.
• In chapter 5, “it denied the spheres’ existence” should be singular genitive 'sphere’s' as I believe the celestial-sphere theory is about only one sphere not several.
• "10^6.4×1017" in ebook chapter six (after the part “thus imposing an arbitrary limit somewhere in excess of”) - the "1017" should be a nested 10 to the power of 17. It's correct in print.
• In the ebook, but not the print version, there is a closing bracket missing in the footnote in chapter 8. The whole equation should read “[(N + M)2 + N – M]/2”
• Is there a period needed after "‘why a puppy?’"? (ch. 8)
• Some captions under diagrams have periods after whole sentences, some don’t.
• “A situation in which something physical becomes unboundedly large, while remaining everywhere finite.” (ch. 8) - ‘finite everywhere’?
• “‘You can’t fool me,’ replies the heckler [...]” (ch. 8) - the comma needs to be after the closing single quote to be consistent with British quoting rules.
• Sometimes it’s “error-correction” (even when the words are used standalone, not as a description of some other noun, like on p. 146 in the 'meanings' section), sometimes it’s “error correction” (without a hyphen, which strikes me as correct when not used as a description of some other noun)
• “p, mf, f” in chapter six should be bold in addition to being italic, per Deutsch's email on 2020-06-27
• “But first we shall have to survive the next ice age; and, before that, other dangerous climate change […]” (ch. 9). Not sure if “climate change” needs to be plural, or, if there is no plural, if the sentence needs to be restructured somehow
• Chapter 9: “Optimism is, in the first instance, a way of explaining […].” I don’t think that paragraph needs to be indented on the first line, as it was not preceded by a paragraph
• Chapter 10, “Socratic problem”: the use of single quotes around this phrase is inconsistent; sometimes they’re there, sometimes they’re not
• In the ebook, in the directions that are contained in brackets in chapter 10, sometimes there’s a space missing between the colon and the opening bracket, looking like 'CHARACTER:[direction…]' instead of 'CHARACTER: [direction…]'
• “science fiction enthusiasts” at the beginning of chapter 11 should be “science-fiction enthusiasts” (with a hyphen)
• Chapter 11: “wingèd Appaloosa” — is the accent on the 'e' needed? (If it is, I’m guessing it’s to signify that the letter ‘e’ is not silent)
• Chapter 11: “And in that case we no longer have an explanation of why they outwardly resemble their originals: the ‘accidental-copying’ idea will no longer do: where did the transporter […]” two colons in a row
• Chapter 11: “We accept much larger unpredictable jolts during others forms of travel […]” should be 'other forms' not “others forms” (note the superfluous 's' in “others”)
• Chapter 11: The phrases “have married sonak” and “already regretting it” are not capitalized in the ebook like they are in print. Also, even though both are at the end of their corresponding sentence, "have married sonak" has the period within the quotation marks whereas "already regretting it" has it outside.
• Chapter 11: “Previously only the two instances of the starship were different, bur soon […]” Needs to be 'but', not “bur”.
• Chapter 11: “When two or more values […]” is indented even though it’s the beginning of a new block.
• Chapter 11: “Quantum optics laboratories” – presumably there’s a hyphen missing between “quantum” and “optics”.
• Chapter 11: “Just as the starship crew members […]” is indented even though it’s the beginning of a new block.
• In the ebook, there is a gap in chapter 9 between “we may learn some matters not so light” and the next sentence. That gap isn’t there in the print version (and it doesn’t seem necessary).
• The diagram for empiricism in chapter 1 spells “generalization” with a 'z' although the rest of the book has British spelling.
• Ebook: the section about the meaning of the beginning of infinity at the end of chapter 12 is malformed; it contains two bullets in addition to a hyphen, and it only has one entry despite having two bullets.
• Chapter 11: “differentiation of history into two or more histories” — should it say 'differentiation of a history'?
• “It is inevitable […]” and “That progress is both […]” in chapter 3 (both right underneath each stone plate) are indented even though they start a new block.
• Chapter 13 sometimes puts periods inside (at the end of) quotes (which is the American convention) rather than after the closing quotation mark (which I believe is the British convention, and is usually done throughout the book and even in places in chapter 13), so there’s an inconsistency there.
• Chapter 14: “Now, why is a flower the shape that it is?” is indented even though it’s the start of a new block.
• Chapter 15: “[I]t has to compete for the recipients’ attention and acceptance with all sorts of behaviours by other people, and with the recipient’s own ideas […]” First it’s multiple recipients, then just one. Should it be consistent?
• Chapter 16 terminology section in the ebook contains an empty and differently designed bullet point
• Several newly begun blocks in chapter 17 are indented on the first line
• P. 444: after Feynman’s block quote, the next paragraph is indented but shouldn’t be
• Chapter 18: “But if spacetime is affected by the gravitation of the cloud, then it would acquire discrete attributes.” Either: 'if spacetime were affected' or 'it will acquire'.
• Chapter 7: inconsistent spacing before and after dialog (at least in ebook)
• In the ebook, footnote to chapter 8, the formula “N (N +1)/2” contains a space between the first N and the opening parenthesis, but in print there is no space. Should be consistent
• “‘Neither,’ was the reply.” (ch. 2) The comma is inside the quote, which is an American convention, whereas most of the rest of the book has such commas outside the quotes.
• Chapter 3, “If it depends on having more memory capacity, or speed, than a human brain, then the outcome would depend on whether we could build computers to do the job.” -> 'If it depended' or 'then the outcome will depend on whether we can'
• Chapter 4, “If it is possible to live indefinitely in a spaceship in space, then it would be much more possible […]“ -> 'If it were' or 'then it is'
• Chapter 4, “Hence it increases the organism’s chances of having offspring in the future, and those offspring would inherit, and spread, copies of the gene.” -> 'will inherit' instead of "would inherit"?
• Chapter 4, “If the truth is that the constants of nature are not fine-tuned […], then this would be an unexplained regularity in nature and hence a problem for science to address.” -> 'then this is'?
• Chapter 4, “In the former case, we must expect there to be an explanation of why the laws are as they are. It would either refer to the existence of life or not. If it did, that would take us back to Paley’s problem: it would mean that the laws had the ‘appearance of design’ for creating life, but had not evolved. Or the explanation would not refer to the existence of life, in which case it would leave unexplained why, if the laws are as they are for non-life-related reasons, they are fine-tuned to create life.” Why “would” and “if it did” etc instead of 'will' and 'does' and so on?
• Chapter 7, “Recall Edison’s idea that progress requires alternating ‘inspiration’ and ‘perspiration’ phases, and that, because of computers and other technology, it is increasingly becoming possible to automate the perspiration phase.” It sounds a bit like Edison said that about computers, but no computers had been built then. Might be clearer to say 'and the fact that…' instead of “and that”
• Chapter 10, paragraph breaks within the same person’s speech are not indented in ebook
• Chapter 12, “and that visitors are never created, destroyed, split or merge” – either 'split or merged' (with a 'd' at the end) or 'never split or merge' (adding 'never' once more to enable switch to active mode)
• Throughout the ebook, there are usually several blank pages (and sometimes inconsistent amounts of them), more than seem necessary, between chapters. That also seems to lead to a bug where clicking on the table of contents provided by Apple Books just gives you a blank page (for some chapters). And sometimes it shows you the last page of the previous chapter (though that may be a different bug).
• Chapter 13, two subsequent paragraphs start with the sentence “As with the apportionment problem […].” A bit repetitive, perhaps?
• Chapter 15 glossary, ebook: entry on inexplicit should be on a separate line underneath the one on explicit
• Chapter 16: blank bullet in terminology section in ebook
• Chapter 17: “If none are found, what would we do then?” I think it needs to be either 'If none were found, what would we do then?' or 'If none are found, what will we do then?' Given the context, the latter seems to fit better.

• Chapter 17, from an email I sent to Deutsch on 2021-06-29:

  The last couple of sentences in chapter 17 read:

  Strategies to prevent foreseeable disasters are bound to fail eventually, and cannot even address the unforeseeable. To prepare for those, we need rapid progress in science and technology and as much wealth as possible.

  I’m guessing instead of “those” you mean “that” (the unforeseeable) since the second sentence seems to be in opposition to the first one and “those” can only refer to “foreseeable disasters”. If I understand correctly, while it is true that we need rapid progress etc for both kinds of disaster, we need it more so for unforeseeable disasters, and that’s what you’d like to stress here. That’s how I’ll change it in the translation, too, if I’m not mistaken.

• Chapter 3: “elementary particle physics” -> 'elementary-particle physics' (added hyphen)

• Chapter 14: “One unusual aspect of the flower–insect co-evolution” – Between “flower” and “insect” there’s an en-dash, but shouldn’t it just be a hyphen, like between “co” and “evolution”?

• Chapter 6: “Pierre Simon Laplace” needs a hyphen between “Pierre” and “Simon” (see https://en.wikipedia.org/wiki/Pierre-Simon_Laplace)

• Chapter 6: “input–output” uses an en-dash between those two words when it probably should be a mere hyphen

• Chapter 5: “mind–body problem” ditto

• The bibliography isn’t really a bibliography. It’s more like a list of recommended works, not of referenced works. The referenced works it does contain often don’t have comprehensive source information (all of them lack the place of publication, for example). And the in-text sources, when given, don’t reference the bibliography entries, nor do they give page numbers or other detailed information so the readers could check the accuracy of quotes etc.

• Several entries in the bibliography are missing subtitles

• Leibniz’s birth and death year are listed in chapter 9 like it’s his first mention, but he’s first mentioned in chapter 6. His birth and death year should be added to his first mention in chapter 6 and removed from chapter 9.

Glitches in index

• says “animal minds” are mentioned on p. 268, but they’re not
• on p. 476 says “creativity and in meme replication” under “memes”; presumably there’s a word missing between “and” and “in”, or the “and” just doesn’t belong there
• misses principal entry for 'background knowledge' (with credit to Popper) in glossary of chapter 1
• misses entry on 'blind spot' in chapter 15
• misses second entry on “Book of Nature” in chapter 1
• misses second entry for Nick Bostrom in bibliography
• misspells Niels Bohr’s name (“Neils”) and is missing entry on Bohr in glossary of chapter 12
• misses several entries on “asteroids” in chapters 3 and 18
• entry for "Balinski & Young Theorem" for page 334 should probably be bold
• misses several entries on climate change that aren’t in chapter 17
• misses entry for Jenny Uglow’s book in bibliography
• has an empty entry for “variation and selection”
• misses entry for Vernor Vinge’s book in bibliography
• “John von Neumann” is currently under letter 'v' but should probably be under letter 'n'
• page numbers aren’t sorted correctly under “neutron stars” (though I suspect that p. 38 simply doesn’t belong in that list)
• entry on “nesting birds” is missing p. 145 (the entry on 'birds:nesting' has it)
• where it says “nature, laws of vii (cont.)” the “vii” should probably be removed
• may want to add '(Tipler)' to entry on omega-point universes
• comma missing between page numbers for “RNA” entry
• “social-choice theory see under choice” is nested under the entry for “Smolin, Lee” but presumably shouldn’t be
• entry for William Gibson lists The Difference Engine but entry for Bruce Sterling does not even though they both co-authored it
• entry on Frederick Soddy has an 'i' missing in 'Frederick' (“Soddy, Frederck”)
• there’s an entry “scientific instruments see measuring instruments” nested under “science fiction” but it shouldn’t be nested
• attributes “what is it like to be a dollar” to Nagel (p. 487) but it should only attribute the bat
• The entry on utilitarianism is missing a page in chapter 14 (about utilitarian theories of art)
• missing entry on volcanoes in chapter 17
• missing entry on gold in chapter 9
• missing several entries on Hades
• missing at least one entry on Johannes Kepler
• page numbers for entry “pulsars” are out of order and may not all belong there
• entry for “significance” has a period after one of the page numbers instead of a comma: “significance vii-viii, 43. 75–6, […]”
• entry on freedom lists p. 51 but I don’t think that page is about freedom
• entry on Fermi’s problem missing at least one page
• entry on book Fatherland missing a page
• entry on ex-nihilo creation has a “see also” for infinite regress; that’s a bit confusing, since (I believe) David says that ex-nihilo creation is possible and valid, whereas an infinite regress is invalid
• the entry on astrophysics says “see also cosmology” with only the word “also” italicized, not “see”, and to be consistent with the rest of the index the word “see” should likewise be italicized
• entry on apes/aping lists page 60 but I don’t think there’s anything related on that page
• entry on apportionment paradoxes missing several entries past page 333
• missing entry for Euclid (just himself, not Euclidian space or geometry) in chapter 18
• entry on “mirrors, semi-silvered” missing at least one entry (potentially 2) in chapter 11 and one in chapter 12
• missing entry for “impulses, electrical” in chapter 1 (for the sentence that contains the string “responding to electrical impulses from our eyes”)
• entry on “magic” missing subentry on 'ad hoc magic' (though the corresponding misquote should be fixed first)
• may be worth adding an entry for “optical nerve” in chapter 4 under entry for “neurons”
• in the entry on “optics”, where it says “see also telescopes; microscopes, eyes”, shouldn’t that be a semicolon between “microscopes” and “eyes” instead of a comma? There is no entry called 'microscopes, eyes' and no entry for 'eyes' under “microscopes”
• may be worth adding an entry on “quantum optics” in ch. 11 under entry for “optics”
• entry on “optics” missing an instance in ch. 15
• there is an entry right after “numbers” on “real” that’s on the top level but should be nested under “numbers”
• “introspection” missing entry in ch. 16
• might be worth adding an entry under “epistemology” on 'laws of epistemology'
• under “energy” it says “needed for knowledge creation” whereas under “evidence” it says “as an essential requirement for knowledge creation”; both refer to the same passage on p. 61 so they should probably have the same wording
• may want to add a subentry for “matter” saying “needed for knowledge creation” at same passage
• pages 114 and 210 under “Popper, Karl” are separated by two commas instead of one
• “data” missing an entry for page 273
• may be worth adding a subentry on 'sensory data' under “data” in chapter 9
• there’s an entry on “Deutsch, David, The Fabric of Reality”. In other book entries there’s a colon between the author name and the title, not a comma
• "inspiration" points to page 440 but it’s 441 (The Ascent of Man is listed as an inspiration in the meanings section of ch. 17)
• may be worth adding an entry on 'justified, true belief'
• entry on justification has a “see also” that should have a colon before “and”: 'see also authority: and knowledge' since “and knowledge” is a subentry on “authority”. Same for entry under “knowledge”
• may be worth putting “(Horgan)” in entry on “‘ironic science’”. And maybe it shouldn’t just be called “science” but 'fields' or something since Horgan also classifies art and philosophy as ironic
• under the “see also” for “information flow” it says “sequences of events in a multiverse”. May be better to say 'in the multiverse'? Otherwise it could easily be misinterpreted to mean there are multiple multiverses. Same under the “see also” for 'splitting:of histories'
• Entry on spontaneous generation missing occurrences in ch. 11, 13, 14
• entry on “reach”, subentry “universal” missing page 87 (where it says Paley’s argument "has universal reach")
• entry on “reach”, subentry “universal” lists p. 388 but I don’t think that page is about universal reach. It does mention reach, just not universal reach
• entry on “quantum suicide argument”: hyphen between “quantum” and “suicide”?
• entry on "strata" missing two pages
• may be worth crediting Herbert Spencer for the phrase "survival of the fittest"
• entry on “truth” has its subentry on “mathematical” nested under “and beauty” but that shouldn’t be nested
• may be worth adding subentries for 'moral', 'universal', 'factual', 'random', and 'scientific' under “truth”
• entry on “consciousness” missing an occurrence in ch. 12
• under “error correction” there’s a reference “see also fooling ourselves” but the referenced entry is called “fooling ourselves, keeping from”, not just 'fooling ourselves'
• may be worth adding a sub entry about the moral imperative of not destroying the means of error correction in ch. 10 to the entry on “error correction”
• not sure “psychology” is supposed to be nested under “proxies”
• entry on “radio waves” lists p. 274 but that’s part of an erratum (it’s a laser message, not a radio message): https://www.thebeginningofinfinity.com/book/errata/#274; luckily, p. 274 is already listed under “lasers”
• “celestial sphere theory” needs hyphen between “celestial” and “sphere”
• entry “chemistry”, subentry “humans as chemical scum” may want to mention Hawking in parentheses here. Same in entry “scum, humans as chemical”
• may be worth adding a subentry 'slavery to' to the entry “genes” (the same subentry exists for “memes”)
• under “correspondence”, the subentry “one-to-one” has a bold page number 193, and that boldness extends through the semicolon up to the next letter 't' in “tallying”; presumably only the page number should be bold
• entry “education” subentry “because I say so” should probably be in quotes like in other places in the index
• entry on “economic forecasts” lists page 439 but it should be 438 (it’s at the very bottom so maybe things got moved around slightly after the index was compiled)
• several of the pages listed under the subentry “creationism and designers” under “design” seem to have nothing to do with creationism but human designers instead
• “design” lists p. 201 but not p. 202
• several entries/pages on “astronomy” missing
• may be worth adding an entry on 'artificial general intelligence (AGI)'
• entry on “potentialities” has square quotes around it, but the subentry “potentialities” under “quantum theory” doesn’t
• entry on “quantum gravity” missing references to ch. 11 and 17; same for subentry “quantum” under entry “gravity”
• lots of entries for “gravity” missing, and it may be worth adding subentries for 'force of', 'rays', and 'fields'
• the subentry “energy” for “gravity” only lists p. 3, but the subentry “gravitational” for “energy” lists both p. 3. and p. 450
• shouldn’t credit Nagel for 'what is it like to be a:dollar' (last page of the index)
• Zeno’s mistake missing entry for p. 190
• missing entry on thermodynamics (but not the second law thereof) in ch. 12
• may be worth adding Balinski & Young’s theorem under “no-go theorems”
• there’s an entry called “real” that should be nested under “numbers”
• “sun” lists p. 47 but that’s not light from the sun that that page talks about, but from another star. As such, it fits better under “stars and solar systems” (where it is listed already)
• lots of entries missing for “stars and solar systems”
• entry on splitting of scientific theories missing summary of ch. 12 and another occurrence in ch. 18
• entry 'the supernatural:and inexplicability' lists pages 423–424 but it’s only 423
• entry on “significance” lists page viii but there’s nothing on significance on that page; the entry also misses occurrences at the end of ch. 1
• entry on simplicity missing Wheeler quote on p. 1; the entry lists p. 5 but there’s nothing about simplicity on that page (the word “simply” surely doesn’t count?)
• entry on “representative government” lists p. 316, but that’s the wrong page. The representative stuff comes in ch. 13, p. 316 is still ch. 12
• entry on 'religions:memes and' is missing a comma between pages 218 and 369
• entry on “geometry” has a “see also” on “space, curvature of spacetime” but the curvature of spacetime isn’t listed under “space” but under “spacetime”
• pages missing for Hilbert, David (not the hotel, the person)
• two pages missing for Hilbert’s hotel in ch. 18
• entry for 'light:sunlight' references page 8 but there’s nothing about sunlight on that page
• entry for “mathematical truth” says “see truth” but should say “see under truth”
• entry for “measure theory for infinite sets” lists p. 458 but there’s nothing about that measure theory on that page, only occurrences of the word “measure” in other contexts
• entry for “measurement” lists p. 299 but that page only mentions measures (in the sense of “measure theory for infinite sets”)
• entry for “measurement” missing p. 458
• entry for “constants of nature see physics, constants of” the “see” part should say 'physics: constants of' (with a colon, not a comma) since it references an entry nested under “physics”
• the entry “correspondence” lists p. 39. That page should be listed under its subentry “of theories with objective truth”. So should p. 241
• entry “conjuring tricks” has a subentry “and measurement” listing p. 229 – that page shouldn’t be listed as it is not about measurements
• entry 'computers/computation:supercomputer simulation predictions' should list not only p. 439 but 438–439
• entry on “conjectures” lists p. 2 but I think it should be p. 4 instead
• entry on “conjuring tricks” lists p. 41 but there’s nothing about conjuring tricks on that page. (There is on the previous page, 40, but that one is already listed under the subentry “and measurement”.)
• entry on “decoherence” missing occurrence in ch. 12
• entry on “causation” lists p. 428 but should probably extend from 428 to at least 429
• under “utopias” it says “see also Golden Age myths” but it should be formatted 'golden age: myths' to be consistent with the referenced entry
• entry “universality”, subentry “universal explainers” is strangely at the top despite otherwise alphabetic sorting. It seems it should be at the very bottom of all the other subentries, underneath “universal constructors”
• entry on “trade” lists p. 427 but it already starts at p. 426 bottom. Since it extends to p. 428 (which is listed), might as well say '426–428'
• entry on “atoms” has a “see also”—only the word “also” is italicized, “see” should also be italicized
• entry on “atoms” misses pages
• entry 'authority:the Enlightenment's rebellion against' lists pages 22-3 but it should only be 22
• entry 'civilization:Athenian' already lists 241–251 so there’s no need to list 246 separately
• entry 'evolution:of creativity' says “see creativity: evolution of” but that target entry is not nested under creativity; instead it is mentioned behind another subentry on creativity, namely “as an evolutionary process in the brain”, separated inline by a semicolon, so it’s easy to miss.
• same problem as in the “see also” for “information flow”, entry 'differentiation:of histories in a multiverse' -> there’s only one multiverse, “a” makes it sound like there are or can be many
• several diseases are listed under “disease” despite already having top-level entries, except for cancer. May be worth adding cancer under “disease” as well.
• at least two pages missing under top-level entry for “DNA”
• the entry “electoral systems” has a “see also” for “proportional representation” but that corresponding entry actually says “proportional allocation/representation”
• the items listed under “see also” for “unknowability” are not sorted alphabetically
• entry 'theories:letting them die in our place' cross-references “Popper”, but the target entry is called “Popper, Karl”
• entry 'theories:mistake of separating prediction from explanation' lists p. 326 but it should be 325
• subentry on omega-point universes under entry "universe" may benefit from mentioning Tipler.
• entry “unknowability” has a “see also” that says “undecidable”. But there is no entry called “undecidable”. Also the “see also” entries may benefit from being sorted alphabetically (throughout)
• entry “unknowability” lists p. 221–2 but it’s only on 221
• universal constructors ("constructors, universal") get their own top-level entry in addition to being listed under universality, but “universal explainers” don’t?
• subentry for “universal constructors” under “universality” contains more information than the top-level entry for “constructors, universal”, which strikes me as another consistency
• several entries for “universal explainer” missing
• entry 'universality:universal constructors:DNA as' lists pp. 162–3 but there’s nothing about constructors on those pages. Same for p. 458. Entry “constructors, universal” may contain the same mistakes, I didn’t check
• entry 'universality:of reason' missing a page
• entry 'universality:of the laws of nature' includes occurrences of the laws of physics. Those are not the same: in an email from Oct 19, 2019, Deutsch writes: “I intended ‘laws of physics’ to mean things like quantum theory, and laws of nature to include things like the laws of evolution, epistemology and computation.”
• entry “original sources of theories” says pp. 255–6 but should go through 257
• entry “natural selection”: arguably the listed occurrences on pp. 160 and 210 are not about natural selection but non-natural selection

There were more issues in the index but at some point I stopped writing them down. IIRC, they’re all fixed in the German translation (those that applied).