Anti gay-marriage atheist??

[Esquilax]

I'll be brief.

  

1. The primary evolutionary purpose of a man and a woman is to propagate the species and raising children. 

Is/Ought fallacy.

2. Homosexual men are more than twice as likely to spread HIV and other STDs than straight men, which applies to lesbian woman too. 

And one hundred percent of car accidents involve a driver. Therefore, drivers should not be allowed to drive cars.

... Not that I buy the baseless assertion to begin with, but hey.

3. Homosexual men and lesbians are much more likely to have serious substance abuse problems. 

Don't mistake correlation for causation, though of course what I said for the point above also applies here in full.

4. Gays are not the proper role models to raise children. Children need a real female mom and a real male dad, one of each. All recent studies prove that children are best raised by a man and a woman. New Research on Children of Same-Sex Parents Suggests Differences Matter. 

"Therefore, I am announcing my campaign against single parents and widowers, as well as my new bill to petition congress to require that all married couples everywhere have children immediately!"

Some argue that the link between marriage and procreation is not as strong as it once was, and they are correct. Until recently, the primary purpose of marriage, in every society around the world, has been procreation. In the 20th century, Western societies have downplayed the procreative aspect of marriage, much to our detriment.

Appeal to tradition fallacy, yawn.

As a result, the happiness of the parties to the marriage, rather than the good of the children or the social order, has become its primary end, with disastrous consequences. When married persons care more about themselves than their responsibilities to their children and society, they become more willing to abandon these responsibilities, leading to broken homes, a plummeting birthrate, and countless other social pathologies that have become rampant over the last 40 years. 

Wake me when all marriages have children. Until then, the guy is talking about parents, not marriages. "Married couples," is a subset of "parents," not the other way around: you can't address all parents by targeting your argument to marriage.

Homosexual marriage is not the cause for any of these pathologies, but it will exacerbate them, as the granting of marital benefits to a category of sexual relationships that are necessarily sterile can only widen the separation between marriage and procreation. The biggest danger homosexual civil marriage presents is the enshrining into law the notion that sexual love, regardless of its fecundity, is the sole criterion for marriage.

So people do things that this author doesn't approve of, and therefore gay people should be made to suffer so that his opinions become more strongly enforced at a societal level. How breathtakingly selfish.

If the state must recognize a marriage of two men simply because they love one another, upon what basis can it deny marital recognition to a group of two men and three women, for example, or a sterile brother and sister who claim to love each other?

Why indeed? Notably, the author never provides a reason why, aside from an unstated premise that he personally finds it icky, as though his personal opinions are binding to everyone else.

In fact, I tend to think that's the takeaway to this whole thing: this person has a personal opinion that gay sex is icky- and it's gay sex specifically, since he himself brought up sex as the new purpose of marriage, rather than... say, straight up love- and so he's desperately scrabbling for reasons to oppose it because he knows, deep down, that nobody gives a crap about his opinions at a judicial level. As with every argument people try to make by coming to a baseless conclusion first and then going from there, every single point is fallacious at some level.