In the second chapter of The Moral Landscape, Sam Harris begins with evolutionary evidence regarding cooperation. I want to inject a little Nietzsche into all this. Nietzsche was afraid that evolution, rather than leading to the "survival of the fittest", would lead to the survival of nervous, rapidly reproducing little tribbles -- he didn't put it just that way, but you get the idea. He was also concerned that Utilitarianism, maximizing happiness etc... is the royal road to the universal couch potato. That is, when society gets all this worked out, what we will end up with is a bunch of overly-entertained, and thoroughly reprehensible, bourgeois slugs whose idea of excitement is playing virtual parchisi on their wii.
The question is, can Harris's viewpoint satisfy the existential view that, in fact, we don't want happiness, we want freedom? Well maybe, maybe not. Can we take this all into account when we are looking at the brain and create a society that turns us all into a bunch of ubermensches? Consult Brave New World by Aldous Huxley before deciding whether this is a good idea: a speech by one of the world controllers suggests a world full of ubermensches is not good for collective happiness.
But then, maybe all this talk is a bunch of romantic, 19th century, goolash which we should just forget about and get back to the business of "inventing happiness" as Nietzsche's Last Man says. I mean, what would you have an organized society do, NOT try to make people happy? NOT try to maximize well-being?
Furthermore, Harris does take on the problem of free will and determines(haha) that it is an illusion, I agree. Now, if free will is an illusion, then is there anything to the Nietzchean point of view? Yes, because Nietzsche didn't believe in free will; even though he makes much of creating our lives as a work of art, he does not believe in free will metaphysically. The question is, what is our experience of life? Do we have the sense of creative "fulfillment" -- illusion or not? How do we conceive of ourselves? As admirable? As pathetic? Nietzsche is more concerned about our will to be creative than about whether metaphysically there is anything like "free" will. Can we change society to create one where people feel more "powerful" and creative in this sense? Can science do this for us? a priori I don't see why not.