Monday 31 October 2011

Question Begging on a Grand Scale

The Fallacious Case for Homosexual "Rights"

In the debate over homosexuality and homosexual "rights", the pro-homosexual camp makes a gratuitous assumption: homosexuality is a genetic, physical orientation.  It must, therefore, be regarded in the same category as the colour of one's hair.  Just as you would not discriminate, argue against, nor condemn someone for skin colour or having red hair, neither would you argue against homosexuality. 

We say the assumption is gratuitous because there is no foundation for it, despite assiduous research and many false alleys along the way.
  It turns out there is too much slam dunk contrary evidence--and as Popper reminds us, logically you need just one piece of verifiable contrary evidence to reject a scientific hypothesis as false. 

The first kind of evidence is behavioural.  People professing to be homosexual have changed to practise bi-sexuality and heterosexuality.  A recent longitudinal, seven year study 
. . . followed 61 subjects for a period of six or seven years, finding that 23 percent of them were, as they reported, successful in converting to heterosexual orientation. An additional 30 percent reported what the Christian Examiner calls “stable behavioral chastity with significate dis-identification with gay orientation.”  Study co-author Stanton L. Jones (Jones conducted it along with Mark A. Yarhouse), a psychologist at Wheaton College, explains:
“The results that we report in our study suggest that change is definitely not impossible, and it’s probably not uncommon, either. That doesn’t mean that change is easy. We think that these results need to be taken into account as a way of respecting the religious freedom of individuals.”
These results, whether valid or not, will likely create angst and debate between those individuals who believe conversion is possible and those who adhere to the notion that people are born gay and cannot change.
Such things, of course, would not happen if there were a homosexual gene.  One cannot change oneself to be a natural red head.  One cannot will oneself to be non-diabetic.

A second kind of contrary evidence is  research done with identical twins.  One study claimed  to have found evidence of a homosexual gene, only to have it shot down by reviewers:

Michael Bailey and Richard Pillard, researchers at Northwestern University and the Boston University School of Medicine, carried out a similar experiment, examining 56 pairs of identical twins, 54 pairs of fraternal twins, 142 non-twin brothers of twins, and 57 pairs of adoptive brothers (1991, 48:1089-1096).  Bailey and Pillard were looking to see if homosexuality was passed on through familial lines, or if one could point to environmental factors as the cause.  Their hypothesis: if homosexuality is an inherited trait, then more twin brothers would be expected to have the same orientation than non-twin or non-biological brothers.

Their Reported Findings

  • 52% of identical (monozygotic) twins of homosexual men were homosexual
  • 22% of fraternal (dizygotic) twins were likewise homosexual
  • 11% of adoptive brothers of homosexual men were homosexual
  • 9.2% of non-twin biological siblings reported homosexual orientations (Bailey and Pillard, 1991, “A Genetic Study of Male Sexual Orientation”)
  • 48% of identical twins of homosexual women were likewise homosexual
  • 16% of fraternal (dizygotic) twins were likewise homosexual
  • 6% of adoptive sisters of homosexual women were likewise homosexual (Bailey and Benishay, 1993, “Familial Aggregation of Female Sexual Orientation”)

Problems with Bailey and Pillard’s Study

While the authors acknowledged some of the flaws with their research, they still were quoted in Science News as saying: “Our research shows that male sexual orientation is substantially genetic” (as quoted in Bower, 1992, 141:6).  However, the most glaring observation is that clearly not 100% of the identical twins “inherited” homosexuality.  If there was, in fact, a “gay gene,” then all of the identical twins should have reported a homosexual orientation.  And yet, in nearly half of the twins studied, one brother was not homosexual.  In a technical-comment letter in Science, Neil Risch and colleagues pointed out: “The biological brothers and adoptive brothers showed approximately the same rates.  This latter observation suggests that there is no genetic component, but rather an environmental component shared in families” (1993, 262:2063).  In fact, more adoptive brothers shared homosexuality than non-twin biological brothers.  If there was a genetic factor, this result would be counter to the expected trend.  Byne and Parsons noted:
However, the concordance rate for homosexuality in nontwin biologic brothers was only 9.2—significantly lower than that required by simple genetic hypothesis, which, on the basis of shared genetic material, would predict similar concordance rates for DZ [dizygotic] twins and nontwin biologic brothers.  Furthermore, the fact that the concordance rates were similar for nontwin biologic brothers (9.2%) and genetically unrelated adoptive brothers (11.0%) is at odds with a simple genetic hypothesis, which would predict a higher concordance rate for biological siblings (1993, 50:229).
A more recently published twin study failed to find similar concordance rates.  King and McDonald studied 46 homosexual men and women who were twins.  The concordance rates that they reported were 10%, or 25% with monozygotic twins—depending on whether or not the bisexuals were included along with the homosexuals.  The rates for dizygotic twins were 8% or 12%, again, depending on whether bisexuals were included (King and McDonald, 1992).  Byne and Parsons commented: “These rates are significantly lower than those reported by Bailey and Pillard; in comparison of the MZ [monozygotic] concordance rate, including bisexuals (25%), with the comparable figure from Bailey and Pillard (52%)” (p. 230).  They went on to observe: “Furthermore, if the concordance rate is similar for MZ and DZ twins, the importance of genetic factors would be considerably less than that suggested by Bailey and Pillard” (p. 230, emp. added).
The debate over homosexual "rights" changes considerably as soon as the assumption on homosexuality being an inherited condition one is born with is exploded.  

12 comments:

David Winter said...

(a) What does the debate about homosexual rights have to do with genetic determination
(b) I think you should perhaps learn a little bit about genetics before you make pronouncements about what is and isn't inherited.

John Tertullian said...

(a) Nature, not nurture.
(b) We await the discovery of the "homosexual gene". Have you found it? Please tell. And while you are at it, we are eagerly waiting the discovery of the "larceny gene" and the "racist gene" and the "domestic violence" gene. Once we have got this down, we can all work on a bit of genetic modification--aka eugenics--to rid the world of all intolerable behaviours, non?
JT

David Winter said...

No, sorry, I would like an answer to (a).

And, although I think it is irrelevant to gay rights, I still encourage you to learn a little about genetics.

John Tertullian said...

What about our answer to (a) was unclear to you? You would be aware that the case for homosexual rights is conventionally predicated upon there being a natural homosexual orientation. Homosexuals, in the popular mind and in contemporary views of civil rights, are presumed to be born that way. Ergo, it is immoral and unjust and anti-human and discriminatory etc. etc. to reject their sexual behaviour and desires as unethical and immoral, or so runs the argument.
If the gene does not exist, that argument falls. The grand edifice of "homosexual rights" would have been built upon fallacious question-begging.
Now, it may be that you would want to argue a case for licit homosexuality upon grounds other than genetic conditioning. Fair enough. It's a free country. But your arguments will doubtless face lots of internecine strife from the rest of the homosexual-rights legionnaires.
JT

David Winter said...

Why is something only natural if it is purely genetic?

John Tertullian said...

Define "natural" as you are using it in the above comment--both as to its denotation and connotation.
JT

David Winter said...

I copied it from you


sexual rights is conventionally predicated upon there being a
natural homosexual orientation. Homosexuals, in the popular mind and in contemporary views of civil rights, are presumed to be born that way. Ergo, it is immoral and unjust and anti-human and discriminatory etc. etc. to reject their sexual behaviour and desires as unethical and immoral, or so runs the argument.
If the gene does not exist, that argument falls


You may want to consider the fact their is no gene for left-handedness...

John Tertullian said...

As we have (presumably) agreed, you don't buy into the prevailing argument to justify "natural" homosexualness. Fine. Neither do we. You would, however, one presumes, acknowledge the febrile search for a homosexual gene. What then would be your argument for homosexuality to be declared and regarded as a "human right"?

On the matter of left handedness, the claim, of course, has been made that a left-handed gene has been discovered.
JT

David Winter said...

Well, I don't think naturalness has much to do with anything. But homosexuality is obviously a natural part of human sexual variation, and there is obviously a genetic competent to sexuality ( a fact even the cherry picked paper you cited points to if you bother to understand heritability). But many traits have no genetic component and are still perfectly natural and innate.

As far as the case for gay rights, I've never heard an argument as why we should discriminate against people based only on who they happened to fall in love with.

John Tertullian said...

So, to understand your argument aright, viz: "one should never discriminate against people based only on who they happen to fall in love with" we need firstly to define "love" in this context as erotic desire. We presume that you would be comfortable with that definition, since we are talking about homoerotic love in our discussion on the ethics or unethical nature of homosexuality.
Your argument would imply that one must regard as perfectly acceptable and right such sexual activities as bestiality, paedophilia, and necrophilia provided that the participant(s) assures us that he or she has "fallen in love" with the object of their carnal desires? As you say, one could not possibly discriminate against people based on who they happen to fall in love with.
Great ethic there--and equally to the point--why? On what sky hook are you going to hang your grand ethical principle, "Any sexual activity is OK if you have fallen in love with the object of your desire and the object of your desire does not object". The next question to your grand pronouncement would be, "Why?" On what basis or argument would you ground your particular sexual ethic? Clearly not "nature" since you have already excluded that as an adequate ground for ethical decisions and actions.
JT

David Winter said...

I said I hadn't heard a good argument. There are good arguments against bestiality, paedophilia, and necrophilia. I've yet to hear to hear one against homosexuality.

John Tertullian said...

One would have thought you have made an excellent argument for bestiality, paedophilia and necrophilia, by your own lights. Maybe it is just too uncomfortable to be consistent, but as they say, what's sauce for the goose is sauce for the gander.
If your argument for homosexual rights and homosexuality is to be grounded on "true love", then it becomes inconsistent special pleading to exclude the others.
And, we notice that you carefully elide the challenge to declare your "sky hooks". Not surprising.