If you are really interested in the actual issue of genetics at population levels, you can read my reply to uke over. It is an actual case on this issue. If you just want to quarrel, then don't and just read this post instead.

First of all, note that I don't disagree with you on human freedoms, mandated eugenics is fascism and it can be objected to on that ground. But to make objections to eugenics merely normative, like you do in number 1 and 3 that rests on normative assumptions, is dangerous. You don't only make eugenics a political issue, you make it only a political issue. Human freedom no more decides the soundness of eugenics anymore than it impacts how rocks fall (which is to say that at best we might have a minor impact, but the falling nature of rocks isn't going to change much).

Number 2 relies on forecasting the future, and I'm not really into psychic practices. "Curing" genetic disorders seems somewhat hopeful, do you intend to swap out every gene in people's bodies and remove any resulting traits to boot? But of course, I agree that we don't know what the future brings.

The history of evolution has been brutal "eugenic" practices, done by both nature and man.

The slaughtering and sexual selection away from IQs below 50 created the brains we have today.
The entire northern European continent has white skin because black skin was brutally selected against
Humans are terrifically weak because brute strength was selected against
Humans are naked and thus vulnerable because hair/fur was selected against.
Humans are immune to many terrible diseases because poor immunity was brutally selected against (just look at what happened to native tribes)
Human children are helpless, hopeless creatures for many years (far longer than other animals) because slow development was selected for.
Entire branches of humans (neanderthals, others which we'll likely find yet) have been genocided by our ancestors, making the resources available for our particular clan that now rules the world.

The point is twofold:
1. We've developed a huge number of weaknesses, far worse than anything you're suggesting eugenics might do, that have made us what we are today.
2. The brutal selection in favor of individual and even race-based traits (to the point of killing off all members of even other human species) has been hugely positive.

The idea that we couldn't, theoretically with our knowledge today, greatly positively influence the makeup of the human race and maximize its quality is ridiculous. There are ways to preserve complete diversity while greatly reducing the incidence of unwanted traits.

These days, public policy is even creating large-scale negative eugenics. Income redistribution to losers and early breeders is creating huge breeding imbalances, where the intelligent and forward thinking have far fewer kids. See what that looks like in a few generations. You warn about the danger of eugenics, but why not that? That seems far more likely to do lasting damage to the human race; intellectually and practically worthless people, a part of which is likely genetic, are outbreeding everyone else, both in volume and time between generations.

I have no problems with any of these, and number 4 is very important. But a person calling a mother who elects to bring a child with Down's into the world for "immoral"... well the person doing that name-calling is dangerously close to what I would call "evil", and that is not a word I use lightly.

Your moral weightings are pretty disproportionate, imo. Let's go through it.

Mother who kills unborn baby because she doesn't want stretch marks: fine
Mother who kills unborn baby because she doesn't want a ******: fine

Mother who enables massive suffering by poisoning her unborn child to give it down-syndrome like symptoms: evil
Mother who enables massive suffering by choosing to bring a down syndrome child into the world: fine, even though the result and life experience and burden is absolutely identical to the above.
Person who thinks that the mother above is acting immorally in causing the suffering by having the child: "dangerously close to what I would call "evil"" according to tame_deuces.

Put together, you don't think your belief set is a tad unbalanced?

You know some with down have jobs and can talk and stuff.

Okay? I'm granting you there are known interactions like the one you mentioned and unknown interactions that we can't yet see because we don't have the lights we need. But is the conclusion from this that we can do absolutely nothing? As far as I know, there is no known way that the major cystic fibrosis genes have a similar benefit. From what we can tell it is a) devastating b) has no known benefits and c) could be significantly reduced in terms of herd prevalence. Is it acceptable to say "no, no, we can't do a single thing about that because maybe there is some benefit we don't know of"?

Also note that the types of proposals I would consider supporting are things like government provided free genetic testing, free abortions, counseling services, information campaigns, etc. As in a body of voluntary proposals that encouraged people to abort a selection of clearly identified and as far as we can tell unambiguously bad genetic diseases. This isn't eliminating cystic fibrosis genes from all 7 billion people. If in the future we turn those metaphorical lights on and discover a massive hidden benefit of herd prevalence of these genes, we can stop this program.

that argument is absurd

having as many children as possible would cause a lot of misery

but utilitarianism is pretty stupid anyway

The pro-choice position does not imply that it is morally fine to have an abortion because you don't want stretch marks. This has been pointed out to you numerous times already in this thread. It is intellectually dishonest to keep repeating your claim here without at least acknowledging and attempting to show how it does.

You have continually asserted without evidence that living with a Down's family member entails "massive suffering." Even though several people have pushed back on this point, you have not bothered to defend it.

A 2011 survey by physicians at Boston Children's Hospital published in The American Journal of Medical Genetics asked families with Down's children questions on this topic. Here are some results:

Now, I think there are good reasons to think that these results are exaggerated. However, this is not describing a picture of "massive suffering" as you've claimed.

Yes, but would it cause more misery than happiness?

I'm taking the liberty of numbering your claims so it's clear which I'm referring to.

Your presentation is a tad unbalanced.

3) Is presented in a way that does not reflect the actual experience of many people with Down Syndrome. Many have happy lives, however their potential for happiness will rate lower than a child born without Down Syndrome. Hence the mother causes the child to have less happiness on average and so acts wrongly.

4) Here though the choice is not between having a healthy child and having a child with Down Syndrome, it is between having a child with Down Syndrome and no child*. If we accept a premise that you seem to disregard, that a child born with Down Syndrome can in fact lead a happy life and enrich the lives of the parents beyond any extra burden incurred, then it is not morally wrong to continue with the pregnancy.

*Some utilitarians will claim that they advocate aborting the child if the parents can try again for a healthy child but this ignores that the many parents will still carry an increased risk of having a child with Down Syndrome and the time and emotion invested already in the pregnancy. I also think it ignores some pretty important considerations in summing net happiness.

The Repugnant Conclusion is a real challenge to utilitarianism and it is clear that many children with down syndrome meet a minimum standard of happiness. I would also argue that if a child's condition is such that the child is bound to suffer then there should be post natal options to either manage or eliminate that suffering.

Is your position that abortion is morally equivalent to killing sentient beings?

I'm sure it's been argued that having children you can't afford to support is immoral.

other civilizations arising on other planets would come to many of the same conclusions we have in mathematics

I don't see why they would necessarily come to the same conclusions on morality

also, humans don't generally get their morals from philosophy or reason

we judge a situation based on emotional, instinctive reactions and only use reason to justify our views after the fact

sometimes people do change their mind on an issue based on reasoning alone but that's the exception, not the rule

I think so

So how do all the arguments change if you don't discover the disease until the baby is three days old and killing it is not illegal?

My position at this moment is irrelevant. In context, I was addressing a specific argument.

All sorts of things have been argued. Whether they've been argued successfully is a different matter.

You may not see *why* they would generally reach similar moral conclusions, but an analysis shows that they do, at least in broad terms. In the first sentence, you don't have a reason why you think civilizations on other planets would agree with our math. It's really just an assertion. So why couldn't one

You're free to make assertions, but unless you have something to back it up, I have no reason to believe you. I certainly agree that emotions play a role in moral judgment, but that's not enough to say that they are "based on" those things, or that reason only supports our emotional reactions.

http://ethics-etc.com/wp-content/upl..._Reasoning.pdf

show me this analysis on the ethics of extraterrestrial civilizations you're referring to

the two arguments are very similar, but I wonder if there would have been the same fuss if dawkins had said it's immoral to have children you can't afford to support

the main difference here is that mathematics comes from rules of logic and from the physical universe, whereas a lot of morality comes from biology

alien civilizations would necessarily come up with much of the same math and physics as us

they would have the same value for pi, the pythagorean theorem, the laws for vector addition and multiplication, complex numbers

some principles of morality are based on basic cooperation so any society would have rules against uncontrolled killing and if they have personal property, they'd have rules against stealing, etc.

but beings with a much different biology than us would not necessarily have the same sexual taboos, etc. and if they were very different from us, their concepts of morality might be different in ways we can't imagine

consider how different bonobo society is to chimpanzee society and how closely related they are to each other (and us)

consider how much difference there is between conservatives and liberals in terms of different moral considerations such as care/harm, fairness, loyalty, sanctity, authority and freedom

now consider what morality might be like for a hive-like social species or for something completely strange

math and physics have to be the same because they have to work

morality has to have some features to prevent wanton destructiveness but beyond that and even within those limits, it doesn't have to be like ours at all

Did you even read the abstract of this paper?

I mean... Thanks for undermining your argument. By providing arguments against your position, you've made it possible for me to sit on my rear end and do nothing at all to strengthen my position.

It's not enough simply to claim that there is a model out there that suggests that reasoning is always biased. There are economic models of behavior which assert that people always do thing according to some sort of internal utility calculation. But that model doesn't do anything to imply that people actually behave that way.

Show me that the mathematics of extraterrestrial civilizations match ours, first.

I like how the second half of your statement has nothing to do with the discussion at hand. That you seem to think that by use of non sequitur that you are somehow making a meaningful statement that advances an argument in some way.

When you're free to make whatever assertions you want, you can make anything true. Why would they come to the same "rules of logic" and what does the "physical universe" have to do with mathematics?

Now prove that morality's basis is solely in biology and not things like "rules of logic" and the "physical universe."

Until you can do that, I'll just ignore the rest of your post, as it seems to be premised on these two assertions.