There isn't an argument.
Amid the negative reactions from young men, a Christian friend has made some very good points.
No, I cannot agree with the artificial distinction you make between a person's sex and a person's gender, whatever you feel you have observed, and however your views lead you to interpret those observations. It is perfectly open to you and others to redefine terms to suit your own opinion or purposes if you wish; you can decide to call a chair a lamp-post (though in its present form it will still retain the intrinsic characteristics and functions of a chair, whatever you personally decide to call it); you could decide to perform major surgery on it in order to make it look a bit more like a lamp-post. You could perhaps persuade or bully others into calling your chair a lamp-post, by threatening them with legal proceedings if they do not, or accusing them of hatred towards chairs that want to be lamp-posts, and vice versa, or declaring them to be ignorant or unintelligent if they persist in calling a chair a chair and not a lamp-post. You could say that for many people, being a chair is about other things than something to sit on, and being a lamp-post is about other things than a means of lighting a street. In short, you can say what you like, but the fact remains that the words 'chair' and 'lamp-post' conjure up historically distinct objects with distinct functions in the minds of the majority.........even, metaphorically, in the minds of chairs that would for some reason like to be lamp-posts (or lamp-posts that would like to be chairs). If this were not so, then neither would hanker after being the other, because neither would have a clear idea of what the appearance and function of the other actually is. 'How people see themselves' is irrelevant. An anorexic sees him/herself as grossly overweight; onlookers see him/her as dangerously underweight; in this case the theory of the validity of 'how people see themselves' could lead to death or irrevocable damage if somebody does not attempt to correct the distorted vision of the anorexic. Why try to correct the distorted ideas of anorexics in order to stop them doing irrevocable damage to themselves whilst in the grip of their delusion, yet encourage those whose ideas about their true gender/sex are equally deluded - and even offer to pay for and perform the permanently damaging surgery that they wrongly think will give them what they seem to hanker after? That is extremely cruel, and there are a number of well-publicised cases of people who have undergone such radical procedures and later regretted it bitterly. In the book of Genesis we read 'Male and female created he them'. We should be seeking to restore that truth in human minds, not encouraging the damaged perceptions which have increasingly developed as a consequence and concomitant of sin.
There is a logical problem with the idea that a person 'knows' themselves to be 'born in the wrong body' in terms of sex/gender. What really defines a man or a woman? It goes way beyond choice of clothing, playthings, interests, career etc., or even emotional response. One can only know what being a man/woman really feels like by actually being one. Saying that you 'have always felt you were a woman', when in fact you have only ever have been a biological man, has to be self-deception. You cannot know what a woman experiences from infancy which defines her womanhood to her. Even she herself might have difficulty in establishing it. Third party observation can only be a very superficial and often misleading guide, and it is interesting that those who are thus confused often go overboard on what they think of as visible evidences of femininity/masculinity. However outward characteristics change. Ladies now wear trousers and become mechanics. Men use make-up and wheel their children around supermarkets. Whilst human customs and desires can, and do, change, the above simple *equation does not. It was established in creation. You say that you are interested in why such people have such desires, since they say that these are not matters of choice. There can be a number of explanations, and they themselves may not know why, but God does, and he has provided both answers, and a solution in Christ. I find that the Bible answers any and every such question if I am diligent to study it and look for the principles contained therein. You, apparently, depend on the opinions of secular philosophers (Mill) and your own observations to shape your thinking. I trust in what I believe to be the wisdom of my Creator, as transmitted through the Bible. We are not going to agree because our criteria for discussion are fundamentally opposed. However there will come a time when the truth will be made evident to all, and in the meantime I think that compassionate Christian friendship, despite such firm disagreement, will do more to alleviate the suffering of confused humanity than any amount of sycophantic political pandering to unnatural desires.
I wonder, if I were a school child who was convinced that I was a monarch, and wanted to be addressed and referred to as 'Your Majesty', whether staff would be instructed to sanction anyone who refused to do this? Actually, according to your reasoning, I would not even have to be convinced of my 'queenliness'. I would simply need to experience and express a desire to be addressed as 'Your Majesty'. if I wore some kind of crown, should that entitle me to use the special toilet facilities that are provided for the Queen when she carries out official duties?
Another friend has written For a thoughtful and informed review of this subject see http://www.wsj.com/.../paul-mchugh-transgender-surgery...