No, I was not making that confusion. I based my decision on a consideration of just that person's mental state. I find a `good' life valuable, though I don't know the specifics of what a good life is, and ceteris paribus, I prefer its existence to its nonexistence.
As evidence to me clearly differentiating killing and `deleting' someone, I am surprised by how much emphasis Eliezer puts on preserving life, rather than making sure that good life exist. Actually, thinking about that article, I am becoming less surprised that he takes this position because he focuses on the rights of conscious beings rather than on some additional value possessed by already-existing life relative to nonexistent life.
Hmm. Yes, it does appear that an less-happy-than-average person presented with a device that would remove them from existence without externalities would be compelled to use it if they are an average utilitarian with a utility function defined in terms of subjective quality of life, regardless of the value of their experiential utility.
The problem is diminished, though not eliminated, if we use a utility function defined in terms of expected preference satisfaction (people generally prefer to continue existing), and I'm really more of a preference than ...
Some people see never-existed people as moral agents, and claim that we can talk about their preferences. Generally this means their personal preference in existing versus non-existing. Formulations such "it is better for someone to have existed than not" reflect this way of thinking.
But if the preferences of never-existed are relevant, then their non-personal perferences are also relevant. Do they perfer a blue world or a pink one? Would they want us to change our political systems? Would they want us to not bring into existence some never-existent people they don't like?
It seems that those who are advocating bringing never-existent people into being in order to satisfy those people's preferences should be focusing their attention on their non-personal preferences instead. After all, we can only bring into being so many trillions of trillions of trillions; but there is no theoretical limit to the number of never-existent people whose non-personal preferences we can satisfy. Just get some reasonable measure across the preferences of never-existent people, and see if there's anything that sticks out from the mass.