The Science of Discworld Iv : Judgement Day, Hardback
3.5 out of 5 (2 ratings)


The fourth book in the Science of Discworld series, and this time around dealing with The Really Big Questions, Terry Pratchett's brilliant new Discworld story.

Judgement Day is annotated with very big footnotes (the interleaving chapters) by mathematician Ian Stewart and biologist Jack Cohen, to bring you a mind-mangling combination of fiction, cutting-edge science and philosophy.

Marjorie Daw is a librarian, and takes her job - and indeed the truth of words - very seriously.

She doesn't know it, but her world and ours - Roundworld - is in big trouble.

On Discworld, a colossal row is brewing. The Wizards of Unseen University feel responsible for Roundworld (as one would for a pet gerbil).

After all, they brought it into existence by bungling an experiment in Quantum ThaumoDynamics. But legal action is being brought against them by Omnians, who say that the Wizards' god-like actions make a mockery of their noble religion. As the finest legal brains in Discworld (a zombie and a priest) gird their loins to do battle - and when the Great Big Thing in the High Energy Magic Laboratory is switched on - Marjorie Daw finds herself thrown across the multiverse and right in the middle of the whole explosive affair.

As God, the Universe and, frankly, Everything Else is investigated by the trio, you can expect world-bearing elephants, quantum gravity in the Escher-verse, evolutionary design, eternal inflation, dark matter, disbelief systems - and an in-depth study of how to invent a better mousetrap.


  • Format: Hardback
  • Pages: 352 pages
  • Publisher: Ebury Publishing
  • Publication Date:
  • Category: Popular science
  • ISBN: 9780091949792



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Showing 1 - 2 of 2 reviews.

Review by

Great! Always nice to see someone mentioning complexity science, and the cosmology and cosmogony parts were really interesting. Also, I love the idea of space bolas!Some quotes: "It's clear that the chicken is only the egg's way of making another egg.""... a proof that the largest whole number is 1. Consider the largest whole number. Its square is at least as big, so it must equal its square. The only whole numbers like that are 0 and 1, of which 1 is larger. QED.""Assigning all puzzling phenomena to the same causes is a standard philosophical error, the equation of unknowns. Asimov put it this way: if you don't understand UFOs, telepathy or ghosts, then UFOs must be piloted by telepathic ghosts."

Review by

Confused. Unsure of it's target audience, with many rambling asides, and some vain attempts not to insult moderate religious belief it never really expresses anything clearly. The interspersed Discowrld segments do actually work better than the previous editions of this series, but it is a non-fiction science book first and foremost, with a bit of Discworld thrown in for marketing and the to emphasize one or two points.The basic premise is a Dawkins style missive against the concept of any gods existing. The authors go through some speculations as to why we might believe in them to start with, and how science has allowed us to progress from those initial concepts to a evidence based culture. They go through with a few references some of the steps in how science works, jumping about from topic to topic as it suits them. Their basic claim is that we can see the universe through a human self-centered viewpoint, or through a wider more dispassionate universe-centric viewpoint. They argue at times convincingly, but frequently less so, that the human centric version is susceptible to bias and wishful thinking. They are less successful at describing a universe-centric view as not succumbing to those problems. Although they mention the issue of attempting to divide any problem into only two pieces, they do not take any steps to look at other alternatives.The main problem - apart from the rambling asides, where they mention all the areas they researched in order to discuss a subject rather than sticking to the point - is the audience. Few if any of the readers will be genuinely agnostic with this book tipping them firmly into one camp. The rest of the readers will already agree with the message, which has been written many times before, more coherently; or they will be firmly religious themselves and no amount of 'evidence' or discussion will sway them, because that isn't the nature of belief, I suspect these readers will mostly dislike the book. If the authors are lucky then it is possible the fundamentalists will call for it's banning or burning, but I suspect the book is too niche, and too rambling to generate that amount of publicity. There is little of added interest for those who are already scientifically inclined. Too few of the arguments are laid out well enough to be worth coping or quoting in the sort of online debates you can feel triggered this book. There are frequent references to the more extreme elements of religion in a 'straw man fallacy' approach that attempts to tar the rest of their (any) religion with the same brush. This is equally true with the Discworld segment, that probably also has a 'no true Scotsman' error in it too. However there is a bonus for LT readers in that an extremely practical and organised Librarian appears in it, who will appeal to many.Not as good as the others in this series, adding little to the explanations of how our world works, and not as well written as many other titles that combat the lack of thinking in many religious positions.