Dialogue On the Causes of Homosexuality

I recently posted a critique of a skit on the Daily Show.  I said this:

I am in favor of gay marriage as policy, and I think the evidence is good that male homosexuality, at least, is the result of a genetic predisposition.  But unlike Stewart, I don't think that anyone who disagrees with me is an ignoramus. Consider the second proposition: we certainly do not know what causes homosexuality.  It is very difficult to establish a genetic cause for any complex human behavior, and it is entirely possible that homosexuality is partly or even wholly due to environmental factors.  It might have to do with physical influences in the womb, or more likely with psychological and social influences. These are the sorts of things about which reasonable people may disagree.  The homosexual community is deeply committed to the biological view.  But enforcing a political orthodoxy is not the best use of satire.

I got a comment from a reader, Z-Tek, on my Keloland blog.  I responded, and he responded in turn.  You can read the exchanges at the above link. I am grateful for the comments, and here respond in detail to the last one.  I said this in a comment to my own post:

Dear Z-Tek: I agree with you that the "latest scientific research" supports the biological view, but the latest research is often wrong; hence the need for subsequent research and testing.

Z-Tek replies:

Your argument concerning the latest research being wrong is lame. The biological evidence has been there for years and has recently been bolstered.

I reply that scientific claims are always subject to critique, no matter how long or how well they have been accepted.  And important scientific ideas like relativity continue to be challenged by dissenters.  This makes science and the challenged ideas stronger, and so one should not brand as heretics someone who challenges a scientific idea, no matter how dear it is. Bear in  mind that I agree with Z-Tek on the matter at hand. Z-Tek goes on:

The alternative to the biological model is that it is not nature but nurture. This reduces homosexuality to a choice (and why would anyone choose it--especially in this society).

Z-Tek is confused here.  Nature and nurture are both influences on us; choice is what happens when we respond to and from those influences.  It is conceivable that homosexuality is caused by environmental influences: perhaps chemical agents present in the womb, or more likely, social and psychological influences operative in childhood.  The great playwright Tennessee Williams obviously thought that his homosexuality had something to do with an overbearing mother.   That would hardly make homosexuality a choice: we don't choose when we are born or how our parents will treat us.

I think it very unlikely that homosexuality is a choice, but even if that were what the evidence showed, it is not clear to me that it would matter.  Religion is obviously a choice, but I think it is a choice that should be respected.  Z-Tek thinks that anything but the biological view plays into the hands of religious bigots.

[The view that homosexuality is not biological] allows for institutionalized bigotry on religious/moral grounds. The argument being that God opposes homosexuality therefore he would not make anyone a homosexual. Therefore it is a choice and consciously sinful.

This is an ad hominem fallacy: because Jerry Falwell believed it, it must be false.  It won't do.  Darwinism is not false because it offends some believers; alternatives to the biological explanation for homosexuality are not false because they gratify some believers.  Z-Tek finishes this way:

The fact remains that the pervasiveness of the behavior is due to biological factors. Calling it "political orthodoxy" is obnoxious and bigoted.

Here Z-Tek confuses the issue.  I have made it clear on the question of causation: I am strongly inclined to believe that homosexuality has biological causes.  To say that is not political orthodoxy, it is merely taking sides on a scientific question.  To say that anyone who questions that view is an ignoramus, that it is "obnoxious and bigoted" even to acknowledge the validity of an opposition, that is political orthodoxy.  Z-Tek and I agree on the scientific question.  But he wants to close off any honest debate.  That is where we part company.