I read "Life's Work" and found it an entertaining biography and inspirational. I admire anyone who can overcome their fundamentalist religious upbringing and come into the 21st Century, where women are no longer under the boots of clergy or men.This comment illustrates why all pro-life people need to be aware of the difference between a scientific claim and a philosophical claim, because random commenters and even scientists will confuses these two types of claims, such as what is going on here.
Re: "embryologists are, and they consistently agree, without significant controversy, that human life begins at fertilization.": You must not have had a graduate level biology class. Your statement is totally false. For example, the most world renowned embryologist, Dr. Lewis Wolpert, is pro-choice:
“What I’m concerned with is how you develop. I know that you all think about it perpetually that you come from one single cell of a fertilized egg. I don’t want to get involved in religion but that is not a human being. I’ve spoken to these eggs many times and they make it quite clear … they are not a human being.”--Dr. Lewis Wolpert, developmental and evolutionary biologist, author of "Principles of Development" and “Triumph of the Embryo”
“I’m also confident that the freshly fertilized zygote is not human, either. There’s more to being human than bearing a cell with the right collection of genes.”--Dr. Paul Myers, developmental biologist
Developmental biologists view reproduction as a cycle, not a starting point with fertilization:
“The idea that "life begins at conception" is not a scientific one. Since the disproof of 'spontaneous generation' (1668-1859), we have known that life only derives from life. Life arose billions of years ago and has continued since as a cycle. Assigning a beginning to a cycle (like the year) is arbitrary.”--Dr. Robert Wyman, neurobiologist
Of course, it's difficult to give a short definition of what a scientific claim is. But we can understand a scientific claim to mean something akin to an observation about the physical world. Science can only investigate physical reality. So any claim that tries to explain or investigate a non-physical aspect of reality is not a scientific claim. The scientific method is a physical method that allows us to investigate certain aspects of the universe. As it is a physical method, it can only investigate physical things. Any claims made about ethics or metaphysics is stepping outside the bounds of science. A claim that cutting a tree down will kill it is a scientific claim -- a claim that it is wrong to cut down a tree is an ethical claim, not a scientific one, even if it is a scientist who is making that claim. So saying that the field of embryology, as embryologists are the relevant experts, has a consensus that human life begins at fertilization is significant. Pointing out that there are pro-choice embryologists is not, because being pro-choice is about making an ethical claim. So an embryologist who tries to claim that abortion is wrong or right is stepping outside his field of expertise to make this claim. He may or may not be right, but he is not a relevant authority any longer.
Now let's look at Anna's comment. Her first paragraph implies the oft-repeated claim that being pro-life is a religious position held by neanderthals who never made it into the 21st century. This is, of course, complete hogwash that isn't worth time responding to. This is Cathy Newman-level bad engagement with your interlocutors' position.
Her second paragraph is interesting, in that she calls Lewis Wolpert an embryologist, and yet after quoting him refers to him as a developmental and evolutionary biologist. The latter is, of course, correct. Doctor Wolpert is a developmental biologist, not an embryologist. This means that he's not an expert on embryology and is not a counterexample to the claim that embryologists are in agreement that human life begins at fertilization.
But this quote doesn't say anything interesting. I would imagine Dr. Wolpert makes a more intelligent case elsewhere (Anna doesn't even source the claim, just alludes to two books that he's written, so I can't check the quote for accuracy). Doctor Wolpert makes the same mistake as Anna does, assuming the idea that life begins at fertilization is a religious claim as opposed to a scientific one. Then he says something bizarre in which, having never read the quote in context, I can only assume he's being condescending toward pro-life people. I doubt he's making a serious argument with his flippancy, which makes it all the more bizarre that Anna would quote it. It certainly doesn't make her case.
The quote from Paul Meyers (also a developmental biologist) more adequately expresses what I'm trying to relay here. Doctor Meyers is making a philosophical claim, that there is more to being human than bearing a cell with a right collection of genes. But that's exactly what you need if we're speaking biologically. If you can't tell what species something belongs to just by looking at it, you can take a blood sample and determine its species by its unique DNA. Of course, philosophically speaking, there's a lot more to being a human than simply having human DNA. Humans are also the kinds of things that can engage in rational thought, have relationships, hold religious and philosophical views, etc. Humans are more than the sum of their parts. But their parts are important in determining what, exactly, they are.
The final quote from Robert Wyman (a neurobiologist) makes the most bizarre claim I've ever seen a pro-choice person make. Life doesn't begin at fertilization, they claim, it began billions of years ago. And that is somehow supposed to show that we can't know when an individual human life begins. Not only in this argument simply wrong (I did not exist in the Jurassic period; there was a definite beginning to my existence), but it proves way too much. If we can't tell when human life begins because human life began billions of years ago, then Dr. Wyman can't prove that he is a human. Perhaps life doesn't begin until you're 80 years old. If we're to take Dr. Wyman's argument seriously, then you can't tell when anyone's life begins. This is clearly absurd, as is this argument.
These are just a few examples of people who not only make bad arguments, but confuse philosophical claims with scientific ones. It's true that embryologists are in constant agreement with this, but in case you encounter the occasional person who tries to refute this claim, knowing this basic distinction will be helpful as you attempt to show the person where he has gone wrong.
[Today's guest post by Clinton Wilcox is part of our paid blogging program.]