Permutation City
Permutation City by Greg Eganby Greg Egan
Hacker ApprovedRanked 13 of 179 science fiction novels by recommenders
Thought-provoking science fiction about consciousness and computation that readers find stimulating and unsettling. Common caveat: the premise and settings seem implausible to some.
Thought-provoking science fiction about consciousness and computation that readers find stimulating and unsettling. Common caveat: the premise and settings seem implausible to some.
36 people gave an opinion
- recommend it
- 34
- criticize it
- 2
- approval share
- 94%
Recommended in 12 of 13 months
- November 2025: recommended
- December 2025: recommended
- January 2026: recommended
- February 2026: recommended
- March 2026: recommended
- April 2026: recommended
- May 2026: not recommended
- June 2026: recommended
- July 2026: recommended
- August 2026: recommended
- September 2026: recommended
- October 2026: recommended
- November 2026: recommended (month in progress)
Why it carries the badge
- 34 people recommend itNeeds 10 or more, met.
- 17 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 12 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Thought experiments on consciousness and computation
“Permutation City is also a must read especially because of its thought experiments around consciousness and computation.”
Comment from 31 Jan 2026 in “Project Genie: Experimenting with infinite, interactive worlds” “It's one of the most serious, mathematically grounded attempts in fiction to grapple with”
Comment from 9 Dec 2025 in “Ask HN: What fiction books would you recommend for programmers?” “far more interesting exploration of consciousness”
Comment from 4 Oct 2026 in “Blindsight (Watts Novel)” Mind-bending, thought-provoking, memorable reading
“That book was like a matryoshka doll but instead stacked dolls there were stacked mindfucks”
Comment from 21 Mar 2026 in “Major leap towards reanimation after death as mammal's brain preserved” “one of the most thought provoking (and upsetting) books I've read in a long time”
Comment from 2 Jun 2026 in “Crystal Nights (2008)” “maybe the two most stimulating scifi novels I have ever read”
Comment from 26 Dec 2025 in “Ask HN: What did you read in 2025?” - Comment from 7 Apr 2026 in “Book Review: There Is No Antimemetics Division”
Relevant to AI and LLMs
“Permutation City is my favorite and would be very topical given today's obsession with AGI”
Comment from 5 Sep 2026 in “Steffen's Polyhedron” “An interesting book about discrete intelligence, given recent advancements in LLMs.”
Comment from 6 Feb 2026 in “Permutation City by Greg Egan” Mathematically grounded, well-crafted science fiction
“It's one of the most serious, mathematically grounded attempts in fiction to grapple with”
Comment from 9 Dec 2025 in “Ask HN: What fiction books would you recommend for programmers?” “Greg Egan based a delightful science fiction novel on this premise.”
Comment from 5 Apr 2026 in “Emotion concepts and their function in a large language model” “maybe the two most stimulating scifi novels I have ever read”
Comment from 26 Dec 2025 in “Ask HN: What did you read in 2025?”
What people warn about
Each mark is one comment
Premise and settings seem implausible
“whose settings aren't particularly "plausible" IMHO”
Comment from 11 Dec 2025 in “Gundam is just the same as Jane Austen but happens to include giant mech suits” “Doesn't the novel assume the consequent (it starts from the assumption that you can do this kind of manipulation with consciousness)?”
Comment from 20 May 2026 in “There Is No 'Hard Problem of Consciousness'”
Other science fiction novels people recommend
The four most recommended other science fiction novels, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| Project Hail Maryby Andy Weir | 117 | 24 | 83% | 12 | — | Approved |
| There Is No Antimemetics Divisionby qntm | 98 | 34 | 74% | 9 | 1.5 yrs6 owners | Approved |
| Blindsightby Peter Watts | 96 | 27 | 78% | 12 | — | Approved |
| Duneby Frank Herbert | 82 | 25 | 77% | 12 | — | Approved |
| Permutation Cityby Greg EganThis page | 34 | 2 | 94% | 12 | — | Approved |
What people said
26 of the 37 comments that mention it, newest first. Each links to the original comment.
“That guy is so ahead of his time, him and Ted Chiang are my fav authors.”
“it also spooked me in a weird way”
“far more interesting exploration of consciousness”
“It's second only to Permutation City in my Egan tier list.”
“Permutation City is my favorite and would be very topical given today's obsession with AGI”
“the fact that you clicked on this discussion means you'll get get a lot out of it”
“might be a nice read for you”
“If this interests you, you may enjoy the book Permutation City by Egan.”
“There are several books from Greg Egan with this idea in mind: Permutation City and Distress.”
“Greg Egan wrote an entire (fabulous) book about exactly that”
“one of the most thought provoking (and upsetting) books I've read in a long time”
“Doesn't the novel assume the consequent (it starts from the assumption that you can do this kind of manipulation with consciousness)?”
“That was a good mindbender indeed.”
“Greg Egan based a delightful science fiction novel on this premise.”
“That book was like a matryoshka doll but instead stacked dolls there were stacked mindfucks”
“You don't even need the computer once instantiated!”
“It's pretty decent and holds up well today despite being written in 1994.”
“Both having slightly different takes on uploading.”
“An interesting book about discrete intelligence, given recent advancements in LLMs.”
“Permutation City is also a must read especially because of its thought experiments around consciousness and computation.”
“The core concept is so well established in the book.”
“maybe the two most stimulating scifi novels I have ever read”
“whose settings aren't particularly "plausible" IMHO”
“It's one of the most serious, mathematically grounded attempts in fiction to grapple with”
“Greg Egan has a book called Permutation City which is pretty interesting”
“I've read Permutation City and Axiomatic both pretty great.”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.