UPDATE: Closing comments for a while, so folks can cool down. As a point on etiquitte, if you find yourself dominating the thread, along with one other person, over a side point, consider and exchange of e-mail.

UPDATE#2: Comments back open. Respect the other people in this thread guys. Don't dominate the conversation with minutiae that primarily interest you and your antagonist. It makes for a depressing, unenlightening read.

I hate to draw Megan back into this, as I sense she's tired of debating abortion. But, I want to address a side-point in that debate which Megan and I have sparred over before, and in the process refine my own thinking over personhood, slavery and abortion. Here's Megan:

But in this case, I think the analogy to slavery is important, for two reasons.  First of all, it was the last time we had an extended, society-wide debate about personhood.  And second of all, as now, there were structural political reasons that it was much harder--nearly impossible--to change slavery through the existing political process...

Listening to the debates about abortion, it seems to me that really broad swathes of the pro-choice movement seem to genuinely not understand that this is a debate about personhood, which is why you get moronic statements like "If you think abortions are wrong, don't have one!"  If you think a fetus is a person, it is not useful to be told that you, personally, are not required to commit murder, as long as you leave the neighbors alone while they do it.

Conversely, if Africans are not people, then slavery is not wrong.  Or at least it's arguably not wrong--if Africans occupy some intermediate status between persons and animals**, then there is at least a legitimate argument for treating them like animals, rather than people.

The difference between our reaction to the two is that now we know Africans are people.  It seems ridiculous to think that anyone ever thought they might not be people.  They meet all the relevant criteria for personhood in twenty-first century America.

But of course, those criteria are socially constructed.  The definition of personhood (and, related, of citizenship) changes over time...

I think the thinking and motives of slaveholders, was more complicated than this. In some cases, they may well have not believed that blacks were "people," but more often they argued that "people" weren't equal.  Here's Alexander Stephens, Vice-President of The Confederacy, for instance, in his famous Cornerstone speech:

The prevailing ideas entertained by him and most of the leading statesmen at the time of the formation of the old constitution, were that the enslavement of the African was in violation of the laws of nature; that it was wrong in principle, socially, morally, and politically....Those ideas, however, were fundamentally wrong. They rested upon the assumption of the equality of races. This was an error. It was a sandy foundation, and the government built upon it fell when the "storm came and the wind blew."

Our new government is founded upon exactly the opposite idea; its foundations are laid, its corner- stone rests, upon the great truth that the negro is not equal to the white man; that slavery subordination to the superior race is his natural and normal condition. This, our new government, is the first, in the history of the world, based upon this great physical, philosophical, and moral truth.

Stephens doesn't so much reject that blacks are persons, as much as he rejects the idea that all persons are are equal. Moreover, slavery was much more complicated than, say, animal domestication. Slave-masters often allowed--indeed encouraged--slaves to engage in acts common among people. Slaves married. Slaves were baptized. Slaves were converted to attend Christianity--and even attended white churches, at times. Slaves and masters exchanged gifts on Christmas. Slaves were allowed to hire themselves out and buy their own freedom. Slaves were manumitted by masters. The point is that what you see in all of that is something more complicated than "Are Africans people?" The better question seems to be "Are black people equal to whites?"

But more than that, core reason an abortion/slavery comparison falls down lay in the actions of the enslaved, versus the inability of action amongst embryos. Abortion is a debate between two groups over the ultimate fate of embryos.  The Anti-Slavery fight was a violent struggle between two groups over the fate of the enslaved, but with the enslaved as indispensable actors. Unlike embryos, black people were very capable of expressing their thoughts about their own personhood, and never held it in much doubt. Whereas the fight against abortion begins with pro-lifers asserting the rights of embryos, the fight against slavery doesn't begin with the abolitionists, but with the Africans themselves who resisted.

I think people who equate the fight miss that crucial distinction. I think that's why they're more likely to invoke John Brown than, say, Nat Turner--it clouds the analogy. That said even in accepting  John Brown as a stand-in for to pro-life vigilantes, you must also say that  pro-life vigilantes generally don't have armed embryos raiding with them. There is no embryo equivalent to  Mackandal in Haiti, the Maroons in Jamaica, the multi-racial Seminoles of Florida, Harriet Tubman, Frederick Douglass, David Walker etc.

The anti-abortion fight relies on people with voices speaking for the presumably voiceless. The anti-slavery fight relies, first and foremost, on the enslaved asserting their own freedom. The works and arguments of abolition don't mean much if the blacks, themselves, don't believe in their personhood. Indeed one of the great arguments for slavery was that the blacks actually liked it, that they wanted to be enslaved. As a pro-choicer, I don't think I'd argue that any child would "want" to have been aborted.

I haven't yet worked this out, but if you're looking for a moral corollary, it seems to me that the ethics of veganism are actually much closer, in that it involves two parties debating the rights of something that can barely conceive of the terms.

I need to think on that some more, though.