It is the exact same argument being made against gay marriage. A man and a woman raising a child is the natural way of things, therefore we should ban gays getting married. Think of how much damage a gay couple could do to a poor little straight kid, right? Sound familiar?
Incest is in another ballpark to consider it because it actually causes GENETIC issues. The only issues you can find is that you believe the kids won't be well adjusted. Personally, I'd rather see a kid with too many parents than not enough.
Let's go find a study that skinny parents raise better kids than fat ones. That should be a good reason to ban fat people getting married. Human history has shown that healthy parents have raised better kids, so we should use the force of the state to prevent them from marrying, right?
I'm glad you know every person on the planet and their reasons for it. You run around talking about liberty and what not, but it's bull****. You only like liberty if it fits what you view is normal.
So to you it's actually not about the kids, because you admit that anyone could marry and divorce any amount of people as often as they like, or have sex with as many people as they like, married or not. The only thing that matters to you is that they can't be officially married to more than one person at a time. That makes it very obvious that it has nothing to do with the kids, you're just against anything that you find abnormal in society. You're simply arguing to preserve the classical definition of marriage, nothing more.
You're positively no different than those who refuse to let gays marry. Every argument you've made has been identical.
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