Wes has posted about this previously, but I wanted to give this more thought after seeing Sam Harris (introduced at the top of the show not as a philosopher but as a "professional atheist") on the Daily Show a couple of days back. You can see the interview here.
As is typical for a short interview like this, not enough gets conveyed about Harris's point for the viewer to really evaluate it, and I have not read his book, but I wanted to say a little about the project of using science to bolster morality.
Yes, if we take human morality to be self-evidently about human well-being (i.e. health, lack of suffering, "fulfillment:" these are where the "ought" comes out of "is"), as Mill, Spinoza, Hobbes, Nietzsche, Aristotle and others have done, then it seems like we could use science to analyze what actually constitutes well-being and what doesn't. Though we can't measure misery, sociologists have plenty of experience coming up with other measures, such as the suicide rate, economic indicators, the results of surveys, etc.
So, the project is reasonable on the face of it, but faces some evident problems, some of which I think are surmountable, some of which are not.
There are methodological challenges, like the problem of "false consciousness" in Marx's sense. What if people in apparently (to us) miserable conditions say that they're satisfied? ...that they LIKE totalitarianism? Mill dealt with this with his "competent judges" response: if they knew what they were missing (e.g. democracy), they would want it. While I think this problem is surmountable, doing so requires deviating from purely quantifiable measures: we would have to, for example, speak to the escapees from totalitarian regimes and ask them whether their current situation is better than their previous, and account for the bias of their being people who had to or wanted to escape. We'd be relying on anecdotal evidence, which frankly should be sufficient to establish that totalitarianism is bad without having to bring in the name of "science."
I am also not overly worried about Freudian questions here like "can people be ultimately satisfied?" Certainly (as Freud admitted) there's a lot we can do to evidently improve people's lot despite any kind of hierarchy of needs that will keep us ever wanting more.
More fundamentally, the moral divergence of the philosophers I listed as buying the basic principle should make it clear that acknowledging a basic connection between concrete well-being and morality does not give you a whole moral system that can be wielded as a political weapon in the way Harris desires. How should general utility and individual rights best be balanced? How should different goods for an individual (e.g. health vs. Nietzschean fulfillment) be balanced? Must each person (and what exactly constitutes a person?) always count as "one" in the utility calculus under all circumstances (including murderers)? The history of philosophy would have been much simpler if science was able to hand us answers to these questions, but each of them involves a normative component that goes beyond a basic recognition of human flourishing as good.
I've said elsewhere that "new atheists" like Harris are less philosophical than political, and I certainly am in favor of grounding morality on human well-being rather than following the dictates of scriptures, but the smart political move seems to me not to try to get whole cultures to reject scripture (which just isn't going to happen) but to encourage moderate elements within these societies who interpret their scriptures according to modern values, i.e. who read them as advocating human well-being rather than jihad or intolerance.
Yes, we have to find shared values to further the goals of world peace and removal of mass suffering, and these values will have to be values that stem from our humanity, which is the only thing that all the far-flung cultures have in common, but of course religions need not be enemies of this endeavor, and can in fact keep at their traditional task of promoting whatever values are already in place in a society. Yes, this mechanism can be destructive, both through excessive conservatism (e.g. resistance to acknowledging the full personhood of women or minorities, irrational evaluation of sexual mores, etc.) and radicalism ("killing a fetus/animal is tantamount to murder and so the killer must be killed!"), and in some situations science can help here (e.g. showing that masturbation is not harmful or that people will be psychologically messed up if they are forced into roles according to caste), but I can't see that on the whole this appeal to moral scientism has the potential to accomplish political goals: the people who would be swayed by Harris's arguments will be ones that would likely agree with his conclusions even prior to his appeals to science.
That said, there's certainly a rationale for harping on political positions without hope of directly changing our current laws in the foreseeable future (see Nader, Ralph), and I, too, share John Lennon's dream of no jingoism of any sort, but Harris's approach involves a denial of the social reality that religion holds a deep-seated place in most societies, and this denial strikes me as something other than Lennon's idealism.
(Note that I hope it goes without saying that I would not parrot Harris's silly statements here about the Pope and other matters.)