# Permutation City by Greg Egan

34 Hacker News commenters recommended Permutation City by Greg Egan and 2 criticized it, November 2025 to November 2026. It was recommended in 12 of 13 months. It meets the Hacker Approved badge rule.

**Verdict:** Thought-provoking science fiction about consciousness and computation that readers find stimulating and unsettling. Common caveat: the premise and settings seem implausible to some.

## Why people recommend it

- Thought experiments on consciousness and computation (3 comments): "Permutation City is also a must read especially because of its thought experiments around consciousness and computation." ([source](https://news.ycombinator.com/item?id=46832701)) "It's one of the most serious, mathematically grounded attempts in fiction to grapple with" ([source](https://news.ycombinator.com/item?id=46206202)) "far more interesting exploration of consciousness" ([source](https://news.ycombinator.com/item?id=49956407))
- Mind-bending, thought-provoking, memorable reading (4 comments): "That book was like a matryoshka doll but instead stacked dolls there were stacked mindfucks" ([source](https://news.ycombinator.com/item?id=47471794)) "one of the most thought provoking (and upsetting) books I've read in a long time" ([source](https://news.ycombinator.com/item?id=48366131)) "maybe the two most stimulating scifi novels I have ever read" ([source](https://news.ycombinator.com/item?id=46397345))
- Relevant to AI and LLMs (2 comments): "Permutation City is my favorite and would be very topical given today's obsession with AGI" ([source](https://news.ycombinator.com/item?id=49581750)) "An interesting book about discrete intelligence, given recent advancements in LLMs." ([source](https://news.ycombinator.com/item?id=46917845))
- Mathematically grounded, well-crafted science fiction (3 comments): "It's one of the most serious, mathematically grounded attempts in fiction to grapple with" ([source](https://news.ycombinator.com/item?id=46206202)) "Greg Egan based a delightful science fiction novel on this premise." ([source](https://news.ycombinator.com/item?id=47649106)) "maybe the two most stimulating scifi novels I have ever read" ([source](https://news.ycombinator.com/item?id=46397345))

## What people warn about

- Premise and settings seem implausible (2 comments): "whose settings aren't particularly "plausible" IMHO" ([source](https://news.ycombinator.com/item?id=46226890)) "Doesn't the novel assume the consequent (it starts from the assumption that you can do this kind of manipulation with consciousness)?" ([source](https://news.ycombinator.com/item?id=48204294))

## Alternatives hackers recommend

- [Project Hail Mary by Andy Weir](https://hackerapproved.com/p/project-hail-mary.md): 117 recommend
- [There Is No Antimemetics Division by qntm](https://hackerapproved.com/p/there-is-no-antimemetics-division.md): 98 recommend
- [Blindsight by Peter Watts](https://hackerapproved.com/p/blindsight.md): 96 recommend
- [Dune by Frank Herbert](https://hackerapproved.com/p/dune.md): 82 recommend
- [Accelerando by Charles Stross](https://hackerapproved.com/p/accelerando.md): 71 recommend

## Where to get it

- [See price on Amazon](https://www.amazon.com/dp/0575082070?tag=hackerapprove-20) (affiliate link)
- [Bookshop.org](https://bookshop.org/a/130825/9780575082076) (affiliate link)

## Cite as

Hacker Approved, "Permutation City by Greg Egan", https://hackerapproved.com/p/permutation-city/ (counts from 1,795,640 Hacker News comments, November 2025 to November 2026).