Errata

It [a universal Turing machine] can simulate any abstraction in arbitrarily fine detail […]

– p. 1

This part of the sentence is vague. It should say “It can simulate any computable abstraction in arbitrarily fine detail.” That is because there are infinitely many abstractions it cannot compute.

The same problem reoccurs on p. 62 in the terminology entry for universal computer.

Credit to Oliver Waters.

That is also why when one person tells is to the next, it is transmitted faithfully, even though neither party necessarily cares about its faithful replication.

– p. 10

This sentence should read: “That is also why when one person tells it to the next […]”

Credit to Simon Thomas.

You could put all of [these features] together to make a system that can do all three things, but that does not get you closer to an infinitely big repertoire that universal constructors have.

– p. 160

Two mistakes in one sentence! The whole sentence should read: You could put all of [these features] together to make a system that can do all three things, but that does not get you closer to the infinitely big repertoire that universal explainers have.