It is of note that even if utilitarianism has proved to be superior to deontology and the libertarian moral rights theory in the area of killing, we are not allowed to say that it has been finally vindicated; it has to face other challenges in other areas, in particular in situations of distributive justice.

My conjecture is that most people will refuse to let go, even when their lives have become boring (at least in comparisons with possible lives lived by new generations). If this happens, there will eventually be no room for new generations. A kind of collective irrationality will lead to a bleak life for the last generation that decides to stay around. Unless we put and end to the human race (through global warming, for example), before this happens, individual egoism will block the path to a better world.

Once we realise that utilitarianism comes with the idea of blameworthy rightdoing (such as when you push a big man onto the tracks in order to save five lives) and blameless wrongdoing (such as when you don't push a big man onto the tracks in order to save five lives), then utilitarianism all of a sudden appears to give the right answers.

It is true (independently of our conceptualisation) that it is wrong to inflict pain on a sentient creature for no reason (she doesn't deserve it, I haven't promised to do it, it is not helpful to this creature or to anyone else if I do it, and so forth). But if this is a truth, existing independently of our conceptualisation, then at least one moral fact (this one) exists and moral realism is true. We have to accept this, I submit, unless we can find strong reasons to think otherwise.

We can be certain that, if there are conflicting views in different cultures, some of these views must be false. This may help us to transcend our own narrow cultural horizon.

What we need is legislation, not negotiation, for the entire globe.

Utilitarianism condones killing of innocent human beings, even murder, if it makes the world a better place.