Diaspora.

1) "The conceptory was non sentient software, as ancient a Konishi polis itself. Its main purpose was to enable the citizens of the polis to create offspring: a child of one parent, or two, or twenty—formed partly in their own image, partly according to their wishes, and partly by chance. Sporadically, though, every teratau or so, the conceptory created a citizen with no parents at all. In Konishi, every home-born citizen was grown from a mind seed, a string of instruction codes like a digital genome. The first mind seeds had been translated from DNA nine centuries before, when the polis founders had invented the Shaper programming language to re-create the essential processes of neuroembryology in software. But any such translation was necessarily imperfect, glossing over the biochemical details in favor of broad, functional equivalence, and the full diversity of the flesher genome could not be brought through intact. Starting from a diminished trait pool, with the old DNA-based maps rendered obsolete, it was crucial for the conceptory to chart the consequences of new variations to the mind seed. To eschew all change would be to risk stagnation; to embrace it recklessly would be to endanger the sanity of every child."

2) "Yatima's clone started up in the gleisner body and spent a moment reflecting on vis situation. The experience of 'awakening' felt no different from arriving in a new scape; there was nothing to betray the fact that vis whole mind had just been created anew. Between subjective instants, ve'd been cross-translated from Konishi's dialect of Shaper, which ran on the virtual machine of a womb or an exoself, into the gleisner version which this robot's highly un-polis-like hardware implemented directly. In a sense, ve had no past of vis own, just forged memories and a secondhand personality... but it still felt as if ve'd merely jumped from savanna to jungle, one and the same person before and after. All invariants intact. The original Yatima had been suspended by vis exoself prior to translation, and if everything went according to plan that frozen snapshot would never need to be re-started. The Yatima-clone in the gleisner would be re-cloned back into Konishi polis (and re-translated back into Konishi Shaper) then both the Konishi original and the gleisner-bound clone would be erased. Philosophically, it wasn't all that different from being shifted within the polis from one section of physical memory to another—an undetectable act which the operating system performed on every citizen from time to time, to reclaim fragmented memory space. And subjectively, the whole excursion would probably be much the same as if they'd puppeted the gleisners remotely, instead of literally inhabiting them. If everything went according to plan."

3) "Twelve dimensions? Ve'd felt so besieged by the realist backlash that ve'd never even considered doing more than defending Kozuch's six against the charge of 'abstractionism.' Twice as extravagant? It certainly would have been in the twenty-first century, when no one knew how long wormholes really were. But now? Blanca shut down the avatar and began a fresh set of calculations. Kozuch herself had never said anything so explicit about higher-dimensional alternatives, but the avatar's educated guess turned out to be perfectly correct. Just as a 2-torus was the result of expanding every point in a circle into another circle perpendicular to the first, turning every point in a 6-sphere into a 6-sphere in its own right created a 12-torus—and a 12-torus as the standard fiber solved everything. The symmetries of the particles, and the Planck-Wheeler size of their wormhole mouths, could arise from one set of six dimensions; the freedom of the wormholes to take on astronomical lengths could then arise from the remaining six."

4) "'I keep asking myself, though: where do we go from here? History can't guide us. Evolution can't guide us. The C-Z charter says understand and respect the universe... but in what form? On what scale? With what kind of senses, what kind of minds? We can become anything at all—and that space of possible futures dwarfs the galaxy. Can we explore it with out losing our way? Fleshers used to spin fantasies about aliens arriving to 'conquer' Earth, to steal their 'precious' physical resources, to wipe them out for fear of 'competition'... as if a species capable of making the journey wouldn't have had the power, or the wit, or the imagination, to rid itself of obsolete biological imperatives. Conquering the galaxy is what bacteria with spaceships would do—knowing no better, having no choice. 'Our condition is the opposite of that: we have no end of choices. That's why we need to find another space-faring civilization. Understanding Lacerta is important, the astrophysics of survival is important, but we also need to speak to others who've faced the same decisions, and discovered how to live, what to become. We need to understand what it means to inhabit the universe.'"

If I had read this book 10 years ago (or even 5), it might have felt like a revelation. Reading it today feels like entering a cul-de-sac.

Looking around it helps me understand a couple of things, though: How hard sci-fi works (or why it doesn’t), for one; what makes transhumanism so repulsive (and profoundly boring), for another.

Hard sci-fi is more science than fiction – or at least it tries to be. Equipped with enough knowledge about math, physics or whatever science of choice to go above the reader’s head, but not enough to enter scientific discourse itself, hard sci-fi is, I think, best understood as playing with potential scientific theories without ever having to spell them out. As such it’s not so much an exploration of a few wild ideas but the exploitation of some narrow ones.

This can be very interesting (in Egan’s case, the idea of biological, i.e. physical computers “running” completely alien and hermetic forms of life existing in non-physical dimensions is really fascinating) or extremely boring (again in Egan’s case, using an imaginary fundamental physics based on wormholes just to stack trillions of universes on top of each other becomes really tedious really quickly).

But without a strong fiction component, the whole thing gets boring either way – whether we race through universes (Egan) or centuries (Vinge), whether there’s a mystery to understand or a puzzle to solve, the plots tend to be extraordinarily simple, the stories (and characters) extraordinarily flat.

And this connects to the problem(s) with transhumanism: Instead of embracing our socio-biological nature in all its random gore and glory as the source of meaning and purpose (and ideally exploring the contradiction inherent in this), it denounces everything biological as accidental and limited, just to get stuck with the abstract, ungrounded and thus limitless quest for some form of disembodied knowledge which we, limited creatures that we are, can’t ever reach.

The only way to justify this quest is to ignore the nature of complexity, and the only way to implement it is to remove the limits of time – hence the “rushing” (Egan) through eons and universes, enabled by consciousness uploads, nanomachinery and negentropic plot devices like fractal universes.

At the end of this race there’s primarily one thing: limitless boredom – not the readers’, in this case, but the protagonists’. And the few moments of happiness or fulfilment we glimpse are, oh wonder, when they give in to their “ancestral” nature and sacrifice themselves for others, fall in love, or just have some plain old fun. (All of which a true, fully implemented transhumanism would destroy.)

(That the nature of consciousness is the one question left open after the eons Diaspora’s protagonists spent rushing and researching is rather ironic: The best and easiest explanation, not only IRL, but also in the context of the story, would be that consciousness is part of the simulation the protagonists are running to make sense of the world – that it isn’t real, that there isn’t even a question to begin with. This is made more ironic by the fact that Dan Dennett, one of the most prominent proponents of such an “illusionist” account of consciousness, is one of the two sources on the topic named in the references.)

So I’ll rather stick with stories that explore ideas instead of exploiting them, expand my mind instead of enclosing it, let me empathise and be angry, laugh and weep, wonder and wander – and generally enjoy and suffer our limited and accidental existence, the source of and obstacle to all meaning.

As to Diaspora specifically: Egan was surely groundbreaking in establishing the by now well-known tropes of transhumanist fiction (uploads, nanomachinery, contempt for biology and fear of existential threats to humanity). But this not only comes at the cost outlined above, but also bypasses the opportunities for deeper ontological reflection (e.g. taking life existing in non-physical dimensions as a starting, not an end point) in favour of semi-weird physics and semi-abstract math.

Recommended as a historical document; as as work of art, not so much.

A good but demanding read with great concepts for science fiction, but at times it does feel like the author tied several great short stories into one trench coat novel. Mind you, that's not a bad thing, just something to consider.

The first chapter can be seen as its own small and can be read on the authors blog, which i highly recommend! It sets the tone of the story pretty well by introducing a level of "techno-babble" that will be present at other parts of the book. You have the choice to read it and attempt to fully comprehend it or skim through it with the necessary understanding to catch the intent. If you want to understand the techno-babble or broaden your understanding, the author even supplies visual guides and very short explanations on his website, easily findable from the link for the first chapter. www.gregegan.net/DIASPORA/01/Orphanogenesis.html

Pour une fois, je vais commencer par abuser des spoilers pour décrire l'intrigue de ce livre dans le détail.

Que raconte ce livre ?

L'histoire commence à peu près en l'an 3.000. Dans ce futur plutôt lointain, l'humanité s'est divisée en trois factions : les enchairés, qui continuent à vivre dans un corps biologique mais avec des modifications génétiques parfois exubérantes, les gleisners, qui sont passés à un corps robotique bien plus durable et résistant, et enfin les citoyens de polis, qui vivent une existence entièrement virtuelle. Ces trois factions ont apparemment connues une guerre, créant des frontières entre ces factions, qu'il est normalement impossible de traverser.
L'histoire commence avec la création de Yatima par une Polis, afin de renouveler la diversité des citoyens. Celui-ci grandit vite, et s'intéresse aux mathématiques avant de se lancer dans une randonnée chez les enchairés (en mettant en place différents moyens astucieux pour passer la frontière avec un ami). Il s'y fait alors des amis, parce que le temps de la guerre est passé depuis longtemps, et que les enchairés ont appris à accepter la diversité.
Dans le même temps, on découvre qu'une étoile binaire assez lointaine va bientôt s'effondrer, projetant une vague de rayons gammas qui détruirait les enchairés. Yatima décide alors de retourner aider les enchairés à se protéger contre ce drame.
Cette protection ne sera pas efficace, et il emmènera son ami enchairé dans sa Polis (autrement dit il créera un clone numérique de celui-ci qu'il fera vivre dans sa ville simulée).
Ca créera chez les gleisners et les citoyens des polis la motivation pour explorer l'espace Cette exploration les emmènera vers des systèmes spatiaux divers, contenant des traces de vie variées mais toujours surprenante, et dans un cas sur les traces d'une espèce qui utilise les trous de vers pour changer d'univers. Et là, le livre changera de direction (à nouveau) pour m'emmener dans des espaces différents.
Le tout pour amener à une conclusion vertigineuse et solipsiste à la fois.

Ce que j'en ai pensé

J'ai rarement été aussi stupéfait par la puissance de l'imagination d'un auteur. Greg Egan est rigoureux dans ses concepts (et chaque chapitre est en un sens une dissertation sur un aspect de pointe de la science). Mais cette rigueur est le support à une imagination folle. Pour le dire autrement, je n'avais jamais envisagé la topologie mathématique comme un bon support à l'imagination. Pas plus d'ailleurs que l'utilisation des micro-dimensions des théories quantiques ...
Rien que ça est fou.
Mais la manière dont ces chapitres s'enchaînent, avec des concepts différents, des idées renouvelées, rend les choses incroyables. Pour le dire autrement, un auteur classique prendrait une idée et en ferait un roman Ici Greg Egan prend dix, vingt idées fortes de la science moderne pour en faire ce que je ne peux que qualifier de chef-d'oeuvre éblouissant.
Et ce chef d'oeuvre tient aussi parce qu'Egan a su, je trouve, progresser sur les aspects traditionnellement faibles de son écriture : les personnages sont reconnaissables, ils ont des traits de caractères identifiables et des motivations claires. De la même manière, même si la plupart des décors sont virtuels, ils sont aussi parfaitement lisibles. Et ces éléments, qui péchaient habituellement, deviennent cette fois-ci des soutiens pour nous emmener toujours plus loin dans un vertige hyperspatial.
Et l'un des trucs que je trouve le plus incroyable, c'est que ce livre réussit à éviter totalement l'écueil des détails aberrants temporellement. Parce que le livre commence par parler de réalité virtuelle, quelque chose qui prend de la réalité "assez rapidement", parce que c'est une technique, plus qu'une science. Et se tromper dans le choix d'une technique peut arriver facilement. C'est à mon sens pour ça que l'implémentation des polis n'est qu'assez peu décrite. Et c'est tant mieux.
Donc une bonne histoire, dans un futur aussi lointain que Greg Egan pouvait l'imaginer, avec une imagination forcenée. J'ai en fait énormément aimé ce roman, et je ne peux que vous le recommander si vous avez une bonne culture scientifique et considérez que ça peut être le bon support à l'imagination.

I've seen it described as "diamond-hard SciFi", it might even be an understatement. It starts off being confusingly abstract. After ~15% it gets more coherent, slightly more corporeal, though never entirely so.

Even through its abstract and detached universe, it revolves around modern issues of reality, subjectivity of perception and even memetic reality bubbles.

There's a lot to get from this, provided you can keep your mind clear enough to absorb the weirdness of it all.