How can homosexuality be immoral or contrary to natural ends if there is a genetic/evolutionary/biological reason for it?

Got this from reddit. "This Ted talk [“Homosexuality- it’s about survival, not sex”] argued that homosexuality exists as an evolutionary means of birth control (by reducing conflict amongst the males for the females) and that the more sons a mother will have the more likely homosexuality chances will increase for the sons.

How can we still argue that homosexuality is immoral/contrary to the procreative faculties if there is an explicit genetic/evolutionary/biological reason for it?"

PS: It seems as though most, if not all of the people who have replied so far are ignorant of Thomistic ethics and philosophy in general. If you do not have any understanding of Thomism then you might as well not reply. Baseless appeals to the will of God are not sound responses.


There may or may not be a genetic/evolutionary purpose for it, but that purpose isn’t creating facsimile marriages that parallel the marriage between a man and a woman. What you wrote doesn’t seem to account for female homosexuality, though the same would apply.


You could use the same argument to support bestiality.

There is no evolutionary necessity of birth control.


Is there any sin in the book (name just one) that doesn’t in some way relate to an evolutionary/biological component?

Society isn’t built on base instincts and desires. It is built on ethics and reason.


That is not the question. The question is whether homosexuality is immoral or not if there is evolutionary cause.

But to respond to your question, explain why evolution justifies marriage then between a man and a woman, but not two women, or two men? Your comment is a red herring. Sure, evolution may not justify homosexual marriage, but it doesn’t justify heterosexual marriage then either.



Life can’t exist without procreation. You don’t need to look very hard to justify relations between members of the opposite sex.

And no, homosexuality is not “immoral”. It’s a state of being.


There is no genetic/evolutionary/biological reason for it. It is a result of original sin and just with all disordered sins, it needs to be rejected. God created man male and female.


This is actually the best reply so far. There really could be some other evolutionary reason that just isn’t shown in homosexuals today.

Still I think it conflicts partially because it shows some biological direction towards homosexuality, which would seem to entail, from a Thomistic point of view, that homosexuality isn’t a perversion but rather a fulfillment of natural ends

And also yes it does deal with females, though to a lesser extent, because female homosexuals would also reduce conflict amongst females.

Maybe not. I haven’t read Thomas Aquinas except for blips and blurps.

You could if 10% of all people fit into that category. But statistically, such sexual deviance do not fit into the same range. You’d also have to demonstrate it in terms a normal sexual relationship (in other words, in a room of 50 men and 50 women, there will still be homosexuals). And we would all agree bestiality is damaging to society.

Think of cancer. You could make the same argument in terms of population control.
Would you claim cancer is therefore OK? The OP is claiming homosexuality is beneficial in terms of evolution - and he/she gave justification. To make the same argument for bestiality or cancer, you’d have to show a benefit.

Of course there is. Menopause and puberty, for one. And the most obvious, you can’t get pregnant while you are pregnant.

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What do percentages have to do with it?
Why is bestiality damaging to society?

Not really. There aren’t as many people practicing bestiality as there are homosexuals, which is why there isn’t as much need of a genetic/biological explanaition for them.

The question was about homosexuality being immoral if there is evolutionary benefit. You basically said it doesn’t matter, gay marriage is still wrong. That is what my “red herring” comment is addressing.

You said marriage, not procreation. To make your argument, you have to show evolution benefit for heterosexual marriage distinct from gay marriage. But as I said, a completely different topic anyway.

Base instincts??? Desires??? I’m not talking about “base instincts” or “desires” but rather on biological functions that tend to point to some end (as Thomists put it). And I’m just pointing it out because it seems as though under Thomistic analysis homosexuality isn’t a perversion of natural ends at all, but rather a fulfillment of them (to an extent of course)

First of all, I’m not merely appealing to evolution to argue for ththe morality of these acts (in fact, I’m not even arguing for them yet, I just want to arrive at the truth) but rather I’m appealing to natural law theory, and how under biological evidence it seems to suggest that homosexuality is natural and not a perversion of natural ends

What? Do you know what ‘red herring’ means?

And yes, that is exactly what I said. I literally answered the question as directly as possible. Just because something has an evolutionary component doesn’t mean that it is moral.

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You probably should read him in depth, along with his defenders like Ed Feser and Oderberg. He’s by far my favorite philosopher and he’s also the favorite philosophy of the Church (Angelic Doctor hehe)

" a red herring is an argument or subject that is introduced to divert attention from the real issue or problem"

OP asked about morality of homosexuality if there is evolutionary benefit. You said it doesn’t matter, gay marriage is still wrong. Please compare the above definition and your comment.

I’m going to stop talking to you now. You aren’t making any sense to me.

@jan10000 You’re pretty smart. Can you give a reply to my reply?

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