I found this opinion piece on bi­sex­u­al­i­ty by Matthew Parris in The Times of London:

In my Notebook column in The Times I have been recording, in an occasional way, candidates for inclusion in a spec­u­la­tive list of truths or nonsenses staring us in the face that we somehow cannot see: things future ages may dismiss with a snort — just as we look with in­creduli­ty at our forebears’ faith in the theory of the four bodily humours or possession by demons. Here is another modern candidate: the idea that there is a set of males called ho­mo­sex­u­als, and another called het­ero­sex­u­als, plus a handful in the middle called bisexuals who can’t decide. This, we shall one day realise, is a distorting glass through which to look at male sexuality.

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Make a horizontal line whose left margin represents a sexual ori­en­ta­tion so completely het­ero­sex­u­al that such men have never felt, however fleetingly, any sexual attraction to another man; and whose right margin represents gay men utterly unteased by any other interest. Mark 30 million dots between these two poles, rep­re­sent­ing each of us men in Britain, located towards left or right depending on the balance of the at­trac­tions we’ve felt in our own life. How will the resulting scatter look as a shape?

If popular talk is to be believed, the shape would trace the silhouette of a wine glass lying leftwards on its side: long, thin stem in the middle, opening out to a big bowl on the left and a small base on the right. The large cluster (at least 80 per cent, the bowl) would be the “s­traight­s”. A much smaller but distinct cluster (perhaps 5 to 10 per cent, the base) would be the “gays”. The stem would be a thin scatter of “bi­sex­u­al­s”.

But if only we knew it, the true shape, I believe, would be closer to that of a champagne bottle lying rightwards on its side, its base to the left, tapering gently towards its mouth at the right. I think a sub­stan­tial pre­pon­der­ance of men are more het­ero­sex­u­al than homosexual, but scattered fairly evenly between 100 per cent and half-and-half; and that the smaller number who think of ourselves as gay are likewise quite evenly dis­trib­uted along the spectrum from the halfway point.

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If I am right, why have both the gay and the straight worlds so fiercely resisted the ambivalent and perhaps fluid analysis I propose?

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Secondly — and this is very important — the idea that many of us have a po­ten­tial­ly variable sexuality opens up the un­com­fort­able pos­si­bil­i­ty of personal choice; and we gays have lived in a tran­si­tion­al era in which we have very much wanted to believe and claim that “God made us” like this, and “we can’t help it”. Whether or not this is true, it is comforting for those troubled by suppressed guilt, and has provided a knock-down argument against those moral con­ser­v­a­tives who say we could choose, and therefore should choose, not to be gay. It has also seemed to rebut the complaint that ho­mo­sex­u­al­i­ty could be “promoted” or that gay men might “corrupt” potential het­ero­sex­u­als. What, however, has not yet dawned on still embattled crusaders for equality is that true equality — equality of self-regard as well as public esteem — will have arrived when we are as careless as a blond or a redhead might be whether or not we were made that way.

Does “I can’t help being black” strike you as a self-respecting argument against racism? That “I can’t help it” is a subtly self-oppressing argument for acceptance does not seem to have occurred to supposedly liberated gay activists, for whom it has always been the easiest way of ending the argument.

But it is in­tel­lec­tu­al­ly sloppy (would you accept it from a child molester?), calculated to close off troubling thoughts about might-have-beens, and no answer to the Christian evan­ge­list­s’ insulting talk of cures for our “af­flic­tion”. We retreat into a simple, bipolar world of can’t-help-it straights and can’t-help-it gays. We push these feelings and people into closets marked “latent” ho­mo­sex­u­al­i­ty, “in-denial” ho­mo­sex­u­al­i­ty and “confused” ho­mo­sex­u­al­i­ty.

I think sexuality is a supple as well as subtle thing, and can sometimes be influenced, even promoted; I think that in some people some drives can be dis­cour­aged and others en­cour­aged; I think some people can choose. I wish I were conscious of being able to. I would choose to be gay.

I do think that sexual ori­en­ta­tion is largely innate. How we express our sexuality is a matter of choice. We should indeed be able to make an unfettered choice of which consenting adults we wish to love, to share our lives with, and to fuck.

It is wrong to dis­crim­i­nate on grounds of inborn char­ac­ter­is­tics (race, gender) and on chosen categories (religion, political af­fil­i­a­tion). Religious identity is clearly a matter of choice, although far too many people un­crit­i­cal­ly accept the religion of their parents.

Like Parris, I don’t care for the I-was-born-this-way defense of sexual ori­en­ta­tion. We should be arguing for the freedom to live our own lives as we see fit.