He has since sort of apologized:
I do not pretend to know how every individual came to their sexual orientation. I regret that my words to express that concept were hurtful and divisive. For that I apologize unreservedly to all that were offended....
Some of our brightest minds have looked at this debate, and up until this point there have been no definitive studies that people are born into a specific sexuality.Note that apologizing for offending people is not the same as acknowledging that he asserted a politically and morally laden claim without providing evidence. What purported to be evidence was simply a second unsupported claim. (Strictly speaking, his follow-up statement merely says he "pretends to know" only how some, not all, individuals came to their sexual orientation. I admire his modesty.)
I won't go into Carson's claim about the alleged connection between prison and the sexual orientation of ex-inmates. (See Mark Joseph Stern's article on the biological basis of homosexuality in men.) I will just ask what difference it would it make if Carson actually knew what he was talking about. Religion is a choice; people convert or embrace a new religion every day. That obviously has no bearing on their status under law. The source of homosexuality therefore tells us precisely nothing about the assertion of gay rights, such as same-sex marriage. Anti-discrimination laws covering gays are legitimate or illegitimate independent of whether one chooses or is born into homosexuality.
So, then, why is a potential Republican candidate talking about this? It is no mere academic interest. Conservatives (or many of them) are invested in this issue because to accept that sexual orientation is not chosen would be to concede that their god creates homosexuals -- and that they cannot do. If homosexuality is rooted in biology, not in choice, the case for its being a sin takes a big hit in their eyes. Carson may not think the issue bears on the rights of gay people (at least that's what he says), but not all conservatives would agree.
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