My general argument against the creation of Unbreakable was simply that no consent is involved in the matter - consent is actually an impossible thing to give in this instance.* The problem with doing things against someone's consent but that harm them to no degree is that from simple intuition, it doesn't really compute (I think this is because NOTHING in the pre-society humans could really have been a non-consensual happiness injection - while now, this is quite possible, in those messed up mental hospitals in films, for example). Is it intuitively right to do no harm? Not really, some of us want revenge. Is it non-contradictory and somewhat intuitive, then? Yes, definitely. Is it intuitively right to respect consent? Yes - even when you do something out of the ordinary. Like force-feeding a birthday cake to someone who doesn't want one, despite having no digestive problems or palette problems with cake.
But the problem here is that though consent seems intuitive, perhaps even more intuitive that not causing suffering, it SEEMS to break down when we state that NO, you heard me, NO, suffering is to take place at all. And if someone does not want something and does not consent to it, then to some extent, I'd argue at least, this counts as suffering. The very thought of not wanting is a form of suffering, and hence consent in the case of the Lovely Birthday Cake Shoved Down Oesophagus, if this causes no suffering at all (AND MOREOVER ACTUALLY CAUSES POSITIVE UTLITY), is a shaky one. Causing positive utility is good (though remember that it is probably wrong to say we have a duty to cause it - you don't know how far is far enough (never-ending task) and suffering, which can do irreparable harm, is probably higher on your to-do list anyway), to some extent. Violating consent is a no-no. So how does it work out? If we still hold to holding consent as one of the building blocks of morality, we say that since one has no duty to cause pleasure (you have a duty, again, to stop harm that you are about to cause, but no similar duty to cause pleasure in others at any point in time), and consent is king, the Lovely Birthday Cake Shoved Down Oesophagus is most definitely wrong, despite tasting so, so good.
But I suppose the problem of "But where do you derive consent from?" is related to the key problem of morality, anyway. Morality is something human as a result of the evolution of reciprocal altruism. How do we do what most people want (humanity's best interests) without violating the wants of others? First we do not cause suffering as most people do not want more suffering, and despite people who want revenge or punishment, the older humanity as a species gets, the less we can get away from NOT putting ourselves in another person's shoes and feeling the pain of their punishment etc. Secondly do not break consent. Except this one, I think is a little bit contentious. You see the thing is, consent is ALWAYS bundled up with suffering. The Lovely Birthday Cake Shoved Down Oesophagus is a special case simply because it MUST by definition involve no suffering at all - and weirdly therefore is a paradox in that it cannot really involve proper breaking of consent, simply because the act of thinking "this is not what I want" is bound to involve some suffering, and if it doesn't, is an utterly meaningless thing to say. So consent IS important, but it has to be tied up with suffering in some way.
BUT THEN, you ask, WHAT DOES THIS MEAN FOR EFILISM? If no one is hurt at all by a doomsday button, again, they must have had consented to the act. Because the act of saying "I don't want this" is suffering. Therefore unless this doomsday button also changes the minds of everyone before they die, they will suffer, and harm will be done. What if they don't know about it before they die? Well the thing is, you have still violated their rights. This is another pillar of human morality. They possessed multiple things, and possibly had positive utility. You deprived them of that. You monster.
But the Sterilisation Doomsday Button is absolutely fine, as I and others before me have said.
In summary: Non-consent without suffering is a paradoxical situation, and any non-consent in such a situation is essentially empty, like I robot saying 'I don't want this'. Consent is important to the human race because we all believe it is, just like non-suffering - and it doesn't cause contradictions like positive utilitarianism. Nuking the world is wrong, but sterilising it is fine.
As a further note, I don't know about Unbreakable. Is consent specifically broken? Unbreakable isn't asked whether she would like to be born or not, BUT, if she did not wish to be born then this would cause suffering in her life, contrary to the definition of Unbreakable. But the fact still remains that she was not consulted, even if she were consulted she would probably say yes. This still SEEMS wrong, but I don't think you'll hear the last from me about it. If you still read this blog, JasonSL, care to lend a hand and help me out here? Much appreciated for the previous insight you gave me, by the way.
*Well not really my original general argument, if I'm implying that. Originally I stated that if Unbreakable came to hate her life (the thought experiment takes her as female I think?) and wanted to die despite being so happy (which is possible since no amount of happiness can eradicate the effort associated with living - I think), one would come to think that the act was wrong. JasonSL responded: "[T]here are probably lots of humans whose opinion is that their life is worth continuing but are mistaken -- they actually are experiencing net negative utility. We don't consider their mistaken ex post ratification of their life to make it right to have created them, so why should we consider Unbreakable's mistaken ex post condemnation of her life to make it wrong to have created her?". I could not respond to this. Still, now, I think to some extent the 'mistaken' part might be a little misleading, as Unbreakable's hatred of life isn't necessarily mistaken - unless you count any dislike of life as suffering and hence rule out this in the first place. She can't suffer, but by hating her life in all likelihood things are going to become a little more uncomfortable. So to be honest, I think JasonSL is right here, but the argument needs a little explaining (for me, at least).