What I'd first like to talk about is what I spontaneously want to call Banks's sense of scale, though there are probably quite a few better ways to put it. Perspective might also be a way to approach it. What I mean really has something to do with his ability to combine the absolutely monumental with the entirely subjective, the intimate, the personal.
There's a cliché saying that sci-fi writers tend to have a terrible sense of scale. This usually has to do with raw numbers that become either patently absurd or absolutely ridiculous when you think about them just a little; the prime example is probably the one million clone troopers from the Star Wars prequels, an army outnumbered thirty times over by Soviet conscripts during World War II alone, tasked with fighting a galactic war.
Banks, of course, consistently avoids this; nowhere does this seem more deliberate than in the statistics section of Consider Phlebas's appendix:
Statistics
Length of war: forty-eight years, one month. Total casualties, including machines (reckoned on logarithmic sentience scale), medjel and non-combatants: 851.4 billion (± <.3%). Losses: ships (all classes above interplanetary) - 91,215,660 (± 200); Orbitals - 14,334; planets and major moons - 53; Rings - 1; Spheres - 3; stars (undergoing significant induced mass-loss or sequence-position alteration) - 6.
Historical perspective
A small, short war that rarely extended throughout more than .02% of the galaxy by volume and .01% by stellar population. Rumours persist of far more impressive conflicts, stretching through vastly greater amounts of time and space... Nevertheless, the chronicles of the galaxy's elder civilisations rate the Idiran-Culture war as the most significant conflict of the past fifty thousand years, and one of those singularly interesting Events they see so rarely these days.
(Consider Phlebas, p. 462)
Avoiding falling into the trap of grossly underestimating just how huge things become on a galactic scale isn't, by itself, that impressive. Anyone can just make up huge numbers. If anything, Banks went in the other direction, which created some peculiar storytelling challenges; at a casual glance, your average sci-fi reader might indeed become wary of the sheer limitlessness of it all. Not necessarily in terms of raw sizes and numbers, but certainly in terms of technological capabilities and societal challenges.
As Banks himself has pointed out in interviews here and there, there's a very good reason most of the Culture stories don't actually linger on the day-to-day life of your average Culture citizen in your average Culture habitat. This is obviously not unique, by any means; all kinds of stories in all kinds of genres tend to focus on one fringe or another of society, fringes being more conducive to juicy, storytelling-enabling conflicts and drama.
The Culture presents a larger challenge to conflict-driven stories than most universes, though. It's a material utopia governed by benevolent (if, sometimes, scheming and mischievous) Minds "close to gods, and on the far side", as Hub itself puts it in Look to Windward. They've perfected their genetics and medicine; they're comfortably living and travelling in space to the point where living on a planet is a weird idea for most, and terraforming would present no issues other than it being an ecologically unsound destruction of wilderness and anyway a waste of matter considering the acquired living space. No galactic civilisation presents a serious military threat, and the ones that might come close have been on friendly terms, often for millennia.
This is not the kind of sci-fi series where dramatic tension arises from the exploration of technology's limitations, possibilities and implications; those things all take a back seat to the characters. This is why the Idiran war is only shown directly in its very periphery, in Consider Phlebas. There are space battles (skirmishes, really) throughout the series, but none of the massive climactic major battles you'd expect from the statistics quoted above. The Idiran war, like the main, stable society of the Culture as a whole, functions rather as a backdrop for the characters to relate to. Nowhere is this more clear, or fantastically executed, than in my favourite exchange from the series:
'A terrible waste, three Orbitals. A responsibility.'
The avatar shrugged. 'An Orbital is just unconscious matter, even if it does represent a lot of effort and expended energy. Their Minds were already safe, long gone. The human deaths were what I found affecting.'
'Did many people die?'
'Three thousand four hundred and ninety-two.'
'Out of how many?'
'Three hundred and ten million.'
'A small proportion.'
'It's always one hundred per cent for the individual concerned.'
'Still.'
'No, no Still,' the avatar said, shaking its head. Light slid across its silver skin.
(Look to Windward, p. 313)
I don't mean to say that Banks is somehow "above" using sheer scale for dramatic effect. On the contrary, sci-fi is a huge potential playground for the imagination and especially in its literary form (with the associated infinite/non-existent special effects budget) he would be mad not to take advantage of it. There're the shellworlds in Matter: ancient, mysterious, huge, and utterly mundane to the people inhabiting them. There's the suicidal skirmish (taking up several pages of text) that turned out to have been measured in microseconds in Excession. There's the airsphere in Look to Windward. No, the reader won't be bored by lack of impressive spectacle.
I just really admire the way he uses that shock and awe to direct his characters, to drive the story forward, to conjure up the emotional connections which make the universe seem so alive.
