I have to admit, that while I find Saletan slightly disorganized at times, he manages to make quite a few people disagree with him, and does it so well.
You need to read the actual Saletan piece, as well as the comments on the two blogs.
For what it’s worth, here’s part of my contribution to the conversation at the “Denialism Blog,” where Mark Hoofnagle, an MD/Ph.D student, proves that we shouldn’t “mistake denialism for debate:”
You obviously feel very strongly that there’s some quality in humanity that can be diminished, but you continue to mix “defining life” with a request to define the characteristics that you personally believe constitute “humanity” or a “person.”
Let’s begin from the assumption that whatever it is that you feel can be diminished in humanity or that can cause you moral repugnance doesn’t come from a religious belief. Perhaps it’s empathy, imagination or simple learning from the history of humanity.
There’s a distinction between the cell produced by fertilization (a more accurate term than “conception”), parthenogenesis, or the various ways to reprogram somatic cells and other cells or groups of cells. It’s the same organization and integrated functioning that is lost at whole brain death with current technology. That’s why you work with embryos rather than gametes, and why Lee Silver’s comment about teratomas is incorrect.
History tells us – this thread reinforces – that when we begin with one point of discrimination allowing intentional acts that disrupt the life span of an individual or groups of individuals, the lines of demarcation are “fuzzy.”
By the way, is that “William” who posted a comment, the William, Saletan himself?