Among the most striking data coming out from analyses of the vote on California's Proposition 8, which amended the state constitution to recognise only opposite-sex marriages is that while the initiative passed with a relatively narrow margin of 52-48 percent; among African-American voters, 70 percent of them voted for the anti-gay measure.

This is all the more perplexing since African-Americans, within living memory, were also victimised by marriage laws. Up till 1967 when the US Supreme Court ruled on Loving vs Virginia, one in three US states had laws making it illegal for a Black person to marry a White, however much they were in love.

William Saletan, writing for Slate.com, offered an interesting explanation for this phenomenon in his Nov 13 column, Original skin - Blacks, gays and immutability. He pointed out that African-Americans, by and large, have yet to see any analogy between race and sexual orientation. To many of them, the colour of one's skin is something one is born with, but homosexuality is something one chooses.

He cited a 2003 Pew Survey which found that among Whites, 39 percent felt that sexual orientation could be changed (45 percent said it could not, 16 percent didn't know). Among Blacks, 58 percent felt that it could be changed (30 percent said it could not, 12 percent didn't know).

There was a 19 percentage-point gap between Whites and Blacks on the belief that one could choose one's sexual orientation.

Saletan wrote: "The mutability question is hardly academic. It has been driving public opinion toward gay rights for decades. In 1977, 56 percent of Americans polled by Gallup said homosexuality was a product of upbringing and environment; only 13 percent said it was inborn. Today, a plurality says it's inborn. That 20-point shift has coincided with a 20-point shift toward the stated acceptability of homosexuality and a 30-point shift toward support for equality in job opportunities."

And it's not just a matter of one belief competing with another belief. Immutability is well supported by science. As Saletan commented, "the most potent force in politics [isn't] spin but science, which transforms reality and our understanding of it."

This shows us what we need to do all across Asia: We need to keep educating our publics about the science. We don't have to do all that much by way of reiterating the message of rights. Once people absorb the fact that sexual orientation is inborn, they can work it out for themselves.

That said, my own experience has been that lesbians and gays are themselves rather conflicted about science. A large number of them resist the message, which hardly makes them convincing messengers to the wider public.

Very broadly, I see two groups: The first would be those gay people who have the intelligence to see that things are more complicated than that and who resist reducing the message into a simple one. Either they do not have a good grounding in science themselves, and are therefore suspicious of a subject they are not familiar with, or they are all too familiar with science, and couch everything they say with ifs and buts.

Of the first subgroup, some of them prefer to speak in terms of social construction, built upon a base of "everybody is bisexual anyway". The argument they are more at ease with is that people should have a right to choose, and there is nothing wrong with choosing to be gay.

That is a valid point, but unfortunately, people will buy the first part of the argument - your sexuality is constructed - but still refuse to buy the second - that one choice is much the same as the other, value-wise.

Of the second subgroup - those who are only familiar with the science - there is a tendency to resist speaking in definitive terms. They are all too aware that science is a process, not a set of answers, and every scientific conclusion is contingent upon a zillion assumptions and methodological particularities.

Yet, changing the public's mind is not really an exercise in educating the public about the intricacies of science, psychology or sociology. Like it or not, it is politics, and politics is, in a big way, a battle of soundbites. It is far more effective to keep repeating four words, "sexual orientation is inborn" - which anyway is well-supported by the general thrust of scientific findings - than to go into a convoluted philosophical discussion about the human will, the construction of reality, and the tiny ambiguities of experimental findings.

Good politicians know that the world is messy, complicated and multi-layered, but they also know that selling a message succinctly is critical to success. It wouldn't hurt for us to imbibe that lesson too.

The second broad group of gay people who resist that four-word sound bite, are by my observation, the bisexuals, who are more often female than male. They feel excluded by the way the message has been so distilled. It is unfortunate because that resistance springs from a misunderstanding (and a miscommunication by the exclusively homosexual persons) of what "sexual orientation is inborn" means.

Too often it is interpreted to denote that sexual orientation is a dyad - one is either gay or straight - when truly it means nothing of the sort. Bisexuality is a sexual orientation in itself, within which one's love and erotic relationships operate.

Bisexual persons sometimes find themselves falling for a guy, other times for a gal, and it gives the appearance of choice. If one doesn't spend a little time thinking about it, one might think that the example of bisexual persons refute the thesis that sexual orientation is immutable. But just because bisexual Karen has to choose between going steady with Christina or John, while gay Benny chooses between Patrick and Steve, does not make Karen's sexual orientation a choice, while Benny's is inborn. They are both operating within boundaries that they did not choose. Just like heterosexual Sophie, who is agonising between Derrick and Jim.

There is no conceptual conflict between the evidence of bisexuality and saying that sexual orientation is immutable.

The proven route for gay activism lies in spreading the idea that sexual orientation is inborn. Sure, it glosses over many details in both the biological and social sciences. But gay activism is politics first and foremost, and in politics, effectiveness counts. Keep your message short and simple. Keep it one that millions of gay and bisexual people can embrace, through their own personal experience, so that they can confidently go out to change minds.

Alex Au has been a gay activist and social commentator for over 10 years and is the co-founder of People Like Us, Singapore. Alex is the author of the well-known Yawning Bread web site.