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And yet the capability is there within the technologies on display in various books. In Use of Weapons a Mind replaces one character with a machine duplicate that exactly replicates her personality and physiology, complete with memory dumps before and after so that when she gets back she will remember having been in both places. In the same book, the main character is a non-Culture mercenary who got the Culture to make him immortal as his first payment. He can be killed, but he’ll never age. Everyone in the Culture thinks that he’s really weird for doing so. Everyone in the Culture uses their drug glands to consciously tweak their mood and mental capabilities, and when they sleep many of them spend subjective weeks playing adventure–fantasy computer games. With all of that ready to hand, you would think that at least a few Culture citizens would have themselves scanned and uploaded into a computer where they can spend eternity doing whatever they way, including learning how to expand their mind into a Mind. Instead most of them choose to die after 400 years. I think Banks just wanted to write a particular type of story, and so he just air–brushed that possibility out so that people would stay people. Also, don't lose sight of the fact that this utopia is really only possible because energy is literally free, in that any quantity of energy can simply be summoned into existence at any time, for no cost. And they never seem to have to plan for how to dissipate the waste heat, ei