A young man living in Georgia in 1859 believes slavery is wrong because the slaves, though differing from white people in obvious physical ways, are the same in morally important ways. His friend is not a slave owner but is intellectually committed to the position that slaves are not people under the law and that the Dredd Scott decision settled this matter appropriately by clarifying that point. He gets aggravated and presents his abolitionist friend with the following:
"Say your barn is on fire. And further say that in that barn there is a little white girl with blond ringlets trapped in one area of the barn and five slaves, adult men all, trapped in another area of the barn. The fire is getting wildly out of control. You can save the girl or you can save the slaves, but you cannot save both. What do you do?"
The young abolitioninst thinks for a moment and then begrudgingly acknowledges that he would save the young girl.
"A ha! So you acknowledge that you don't really believe that the slaves are human in the same way that we are. So if you are not convinced why should I be?"
Does anyone today read that scenario and believe for a moment that the friend demonstrated that the abolitionist movement was built upon false premises or lacked sufficient argument in favor of the ending of the evil of slavery? Does the fact that a young man grew up in a culture that imbedded in him certain prejudices and predispositions that manifest themselves in crisis situations somehow settle the argument whether or not slaves were human beings and ought to be considered people under the law? I can't see how anyone can reach that conclusion.
Now replace barn with lab and slaves with embryos and tell me if that somehow takes a bad argument and makes it good. The burning research lab is flawed on multiple levels, but the most egregious and obvious flaw is that it fails to address the core arguments of the pro-life position in any meaningful way. It is ad hominem to quoque, the intellectual equivalent of yelling, "You did it too!"
As the above example worked only to expose hypocrisy in the arguer and not to substantively address the arguments in favor of abolition, so the burning research lab seeks to expose hypocrisy in the pro-lifer that argues the humanity of embryonic humans. It attacks the arguer and not the argument. It is fallacious to its core.
And that is only one of the many weaknesses of the thought experiment. (May address others later when my schedule lightens up) It is simply not a good argument.
See old posts here and here.