Before continuing with a discussion of what types of change might be acceptable – or accepted – it will be useful to set down some of the technological possibilities.
It is fairly obvious that human bodies will never travel to the stars – to other planets outside the solar system. There will just be no point, when all that is necessary is to pack a series of electronic genomes suited to different planetary environments (or just a program to construct a genome in response to any particular environment which might be encountered). If people like us are still around, we will travel with the templates as electronic versions of ourselves, and download into a constructed local life form when it has been grown. Or more likely we will stay on board our mother ship in its brain and watch (control) events on the ground through appropriate robotic agents.
People will probably never want to give up their individuality; it's on a level with expecting nation states to give up their armies. But individuality doesn't have to travel with bestiality – there are acceptable ways of competing with other people short of killing them; and 'suffering enobles' – great art and philosophy has come out of hardship. People will want to retain the ability to suffer as well as enjoy; without personal growth there is just collective stasis.
One of the easiest predictions is that people as individuals will continue to want to have fun, meaning that on-line gaming and social Virtual Internet Communities (VICs) will continue to test the boundaries of what is permissible. Once it is possible for an individual to be a tiger in a virtual jungle, to inflict and suffer injury, to hunt and kill (usually virtual) prey, and even to be (virtually) killed, is there any doubt that sites will provide such experiences? It is already there, in fact, at today's primitive level of technology. What is currently missing is the direct sensory link between the avatar (Remote Cognitive Representation, in our terminology) doing the experiencing and the owner's mind; and of course the fully-understood wiring diagram for a tiger's mind, or at least the parts of it that are needed for a hunt in the jungle.
People will also presumably be highly reluctant to give up the mating process, although it may come to be rationed in terms of population growth, if economics doesn't get there first, as seems more likely. Collective mating is not a very attractive thought; so we can expect to see the wooing and mating process become (in fact, remain) a prominent feature of VICs. The difference, evidently, will be that physical meeting will not be necessary in order to experience the various stages of a relationship; in fact, it would be possible to explore alternative personalities, not necessarily human, either, before finally adopting a particular personality (or physical form) for a permanent relationship.
It's hard to believe that marriage will survive as an institution. Of course there will always need to be a body of property rights law, matrimonial and other family law, but it will come to look very different from today's law. Polygamy is presumably inoffensive if all parties are willing and if coition is virtual. It feels the same, remember, between Remote Cognitive Representations (RCRs) – but you can't catch AIDS. Perhaps though you could catch something electronic and nasty instead?
While utilization of new cognitive techniques seems a certainty at the level of the individual brain, the energy of the globalization process will equally not be denied. It is not perhaps quite right to call it a collectivization process, but that is not far from the truth. Book One tried to show that while the energy of the nation state denies individuality and human-ness, the globalization process, at first sight paradoxically, does the opposite: it enhances individual rights, individual choice and individual achievement, but within a carefully supervized, rule-based framework, which can only be called collective. The nation state makes rules, by all means, but they are rules for suppression of individuality, made in the single interest of the State itself. Its support for individuals is grudging at best.
Thus the globalization process will encourage and facilitate the creation of Remote Cognitive Collectives. They won't look like that at first: they will be 'dispute resolution forums', or 'joint trading rule supervisory bodies' and the like. But of course they will use technology to achieve their aims – the formation of a consensus solution – and little by little, the RCCs will take shape.
So there is a case to be made for each of the possibilities listed above, and absent an ethical or cultural barrier, they will all probably come to be available to people, who will be able to participate in any or all of them. People? Wait a moment! People will not be people, they will be something – lots of somethings – different. That is the most difficult part of the future to predict. It is reasonably easy to see how the technological possibilities will unfurl; but not at all easy to see how our society will change its rules to accommodate them. When it becomes possible to create a child with any desired set of physical and mental attributes, who is to make the choice?
1 Kurzweil, R The Ray Kurzweil Reader, http://www.kurzweilai.net/meme/frame.html?main=/articles/art0588.html?