Invoking the "slippery slope" metaphor implies that whatever is at the bottom is unequivocally bad. It is not at all clear that is the case here. What I see at the bottom is the unrestricted use of screening to filter out embryos with identifiable risks for traits that would make the life of some future person worse than it might have been. Why would anyone without a religious commitment to the "sanctity" of blobs of human cells think this is a terrible thing?

= identifiable risks for traits that would make the life of
= some future person worse than it might have been

For example, you could screen out people with dark skin, because light-skinned people have more pleasant lives. And you could screen out females with dark hair, because gentlemen prefer blondes and the chemicals in the hair coloring bottles cause cancer. You could screen out anyone with below-average height, because taller people make more money. In fact, you could screen out all kinds of stuff, so that genetic diversity declines to all-time lows.

This is supposed to be an *improvement*?


Maybe there's more to human value than just being healthy and wealthy.

once:

This is supposed to be an *improvement*?

An improvement in what? The human species, or the life of a future person relative to what it might have been?

If the latter, I do think it is a stable and defensible principle that screening is permissible if it be done in the objectively best interests of the future person, whatever those are.

If the former, is biodiversity, or species-health considerations, really a sound ethical principle? Ask yourself if you wouldn't rather be the product of a process that screened our various traits that would make your life worse. I think it is extremely implausible that the genetic diversity of the species would be seriously biologically imperiled by such a practice even if it were ubiquitous, but even it were, it isn't clear to me that this would justify failing to act in someone's best interests when we were otherwise able to.

Axon . .

Which future person's best interests do you think you are looking out for? It's not as though all these embryos which you are screening are one person and you are picking the best possible life for him or her. Each embryo is an individual, when you screen them you choose which ones will live and which will die. The defective embryo will still be worse off because now it will have no life at all, not even a flawed one.

I'm not saying that screening should be banned or that it is wrong, that is for people to decide for themselves. All I'm saying is that it should not be taken lightly and as if it is simply a matter of giving an unborn child the best life possible. It isn't, it’s a matter of picking which unborn child will have any life at all.

thisislissa:

Which future person's best interests do you think you are looking out for? It's not as though all these embryos which you are screening are one person and you are picking the best possible life for him or her. Each embryo is an individual

I am looking out for the interests of persons who will exist. You are correct that I am not looking out for the interests of persons who will not exist. I do not regard that as a callous position; I think it is both reasonable and ethical. Of course every embryo is an individual...an individual embryo. Of course not all these embryos are one person. Nor is any one embryo one person. Embryos are not persons. And no non-person can have an interest in becoming a person (or in anything else).

If the condition you're screening for results in a significantly diminished life expectancy, and, the complications from that condition render that person unable enjoy the benefits of being "alive" would you move forward and implant that embryo? Is chronic pain, invasive procedures, lengthy hospital stays and gradual paralysis a life you would want for your child?

Axon:

Of course every embryo is an individual...an individual embryo. Of course not all these embryos are one person. Nor is any one embryo one person. Embryos are not persons. And no non-person can have an interest in becoming a person (or in anything else).

Axon-

It is disengenuous to say that the embryos do not exist, or do not exist as people. I used to agree with you. I used to think that embryos were not people, unfortunately science does not. Life does begin at conception, believe me I wish it didn’t. I wish I could find some convincing evidence that life begins the moment you exit your mother but I can’t. Whether and under what circumstances we have the right to end that life is a question that some of us are/will be doomed to struggle with. I don't think this is a matter for government intervention, I just think that we should be honest about what screenings, or abortions really entail: killing a future human. You can say that nature kills future humans, and current ones with astounding cruelty, but that does not necessarily give us permission to do so too.

Selauver –

As long as you are talking about me personally, I would never have IVF so any decision I made would involve abortion rather than the decision not to implant. I suppose it would depend on what my future child was diagnosed with. If it was a severe early childhood illness, I would certainly choose to spare them the pain. If the disease would strike later in life, I would find the decision harder. Maybe I’m wrong, but I think that 49 or 20 or even 10 good years are better than none at all.

thisislissa:

It is disengenuous to say that the embryos do not exist, or do not exist as people. I used to agree with you. I used to think that embryos were not people, unfortunately science does not. Life does begin at conception, believe me I wish it didn’t. I wish I could find some convincing evidence that life begins the moment you exit your mother but I can’t.

You are very confused, I'm afraid. I have said nothing about whether embryos are alive or whether they are members of the species Homo sapiens. On reasonable definitions of both these terms, embryos are living members of the species. They're certainly not any other species, and cell division and metabolism are underway, so there's no reason to deny they are alive.

But none of this has anything to do with being a person, or even, more broadly, with being something that can have interests. That, and only that, is what I am denying of embryos. But that makes all the difference. It means not only that it is permissible to disregard their preservation in the interest of future persons, but that it would be unethical not to.

When do they become people with interests? 2 weeks? 6 weeks? 6 months? When they take their first breath of air? If I could figure out where to draw that line I would be all for your theory.

thisislissa:

When do they become people with interests? 2 weeks? 6 weeks? 6 months? When they take their first breath of air? If I could figure out where to draw that line I would be all for your theory.

Do you really believe that, because there is no precise moment when personhood "switches on," embryos must be persons? Just because the transition is vague doesn't mean that there is no transition, that it is a person all along. (I say this assuming that we are not debating the religious doctrine of "ensoulment," although even if we were, there would still be the question of why that should be supposed to occur at conception.)

For what it's worth, I think that your suggestion of 6 months would be the very earliest that is reasonable. The first organized thalamocortical neural activity begins around then, and there is a case to be made that such activity might constitute a minimally sufficient condition for the faintest glimmer of anything you could call experience. I hasten to add that I don't think mere unconsciousness implies lack of personhood (you're still a person when you're asleep), but I do think that nothing that has never had had any experiences at all is a person.

= I am looking out for the interests = of persons who will exist. This doesn't work, as a matter of logic: you've gone circular on us. The "givens" at the top of the proof are all the possible people (all the blastocysts in the IVF dish). The task is to identify which should be allowed to live. There are no limits on the number that should be allowed to live. You've decided that you should look out for the interests of the people that you'll look out for the interests of. Instead, it's much more logical to look out for the interests of all of the possible persons: I promote this healthy person's life, because I think it best for this individual. I reject this unhealthy person's life, because I think it best for this individual. Unless you actually think that healthy people are harmed by the birth of unhealthy people, you can't use the interests of a healthy person to conclude anything about the value of an unhealthy person.