H. Allen Orr's critique of Sam Harris's most recent book is worth a read. Money quote:
Harris’s view that morality concerns the maximization of well-being of conscious creatures doesn’t follow from science. What experiment or body of scientific theory yielded such a conclusion? Clearly, none. Harris’s view of the good is undeniably appealing but it has nothing whatever to do with science. It is, as he later concedes, a philosophical position. (Near the close of The Moral Landscape, Harris argues that we can’t always draw a sharp line between science and philosophy. But it’s unclear how this is supposed to help his case. If there’s no clear line between science and philosophy, why are we supposed to get so excited about a science of morality? After all, no one ever said there couldn’t be a philosophy of morality.)
Dylan Matthews targets another piece of faulty reasoning. Sam has written a response to me on torture. I'll respond when I catch my breath, but here's the piece in the meantime.
The Dish 