I like the fish and whale and border examples. The ancient Jewish fish / land distinction makes sense and there was no reason why it shouldnt be so if it was the most helpful separation for their needs or at least if taxonomy by habitat had no disadvantages. The peanut is a legume but it doesnt affect our day to days lives not to know that isnt a nut. Although I dont think any complex phylogenetics and evolutionary theory would have been needed to explain why a whale was more similar to a cow. Pointing out that it gave birth to live young which was suckled by mammary glands and that it was warm blooded may well have created a 'well wouldnt you know that' moment in ancient times.

How we categorise different things, where we draw the line is often not clear cut. The problem with the argument of Pluto as planetoid or planet is that we can not say on this basis that Jupiter is a planetoid, because it is distinctly still a planet. Another example is the difference between a lake and a pond? Everyone's line seperating the two might be in different place. But equally this doesnt mean that Lake Victoria can be called a pond purely on the basis that there is a blurred line in the middle between small lakes and large ponds. Likewise the existence of grey does not mean that black can be white.

What these arguments are really analgous to are intersex conditions where it can be very difficult to call whether someone is male or female. Indeed there are intersex conditions which are more clearly one or the other sex whilst true hermaphrodites are rare but its clearly a tricky business as to where to draw the line and what should take precedence in determining that line - gonads? genitals? chromosomes? phenotype? sexual orientation? personal feeling?stereotypical behaviours? There were times when gay people could seen as hermaphrodites because the idea of same sex attraction was seen as against nature.

The problem with this analogy is that trans people are not considered to be intersex. They are unequivocally one biological sex or the other with matching gonads, genitals and genes. It is only their self assessment that differs from the reality of their bodies. The argument is as you say that the over riding determent of sex should then not be anything objectively observable but instead a strongly held subjective feelings. This make things more tricksy opening as it does a huge can of philosophical worms.

The Napolean argument touches on this and yes its true it doesnt seem to be a common condition, probably because he's not as well known a figure as others these days. My psychiatric nurse friends tell me there are far more many Jesus's to be found - they having met several in their time. Though its true no one has found any evidence for genetics predisposing one to this specific delusion. There is indeed some evidence to suggest suceptiblity to hormones in utero may result in a trans gender identity via over or under expression of hormones due to genetics. Yet this and some minor brain area differences only really prove that people are telling the truth - that they genuinely feel they should have been born the opposite sex.

There are also genetics markers and brain area changes observable in people who develop schizophrenia. And also genetic markers and brain area changes in those people prone to be very religious. So we know these people genuinely believe what they see as truths, be it that they are being followed by an anarchist cabal, voices talk to them or that they experience a feeling of a divine presence. Yet we do not use their quite genuine experiences as a basis for everyone else having to affirm these experiences as objective truths. Unless of course we live in theocratic dictatorship or think schizophrenic people have a hotline to some higher power.

We support freedom of belief and religious freedom. The argument that " I could point out that if the extent of somebody’s trans-Napoleonness was wanting to wear a bicorne hat, and he was going to be suicidal his entire life if he couldn’t but pretty happy if I could, let him wear the damn hat." is more difficult that it first appears. Of course it will not harm a person to wear a bicorne hat so why they shouldnt they wear it and I agree. But what the argument proposes is that everyone must also affirm his belief that he is Napolean. This is asking a lot. It insists that the rest of the world keep up a facade in order to protect the feelings of would be Napoleans. Whilst that can be a very sweet thing to do - cf the films Lars and the Real Girl or La Vita e bella, it does mandate mass mendacity.

I agree that if theres no harm in holding up a pretence and a person will be happier then there's a good argument for doing it - which is widely respected up to a point in the acceptibility of white lies- the building block of social interactions. "I like your new hair cut" or "I cant make tonight because I have a cold" are fairly inoccuous white lies which do more good than harm. But when it comes to Chinese officials making a fake show field of wheat to demonstrate to Mao their glorious leader the success of his agricultural policy when in reality millions are starving, then protecting someones sense of their copetance is distinctly problematic. The potential for harm must be outweighed by the potential for good.

“If it’s a psychiatric disorder, then attempts to help transgender people get covered by health insurance, and most of the ones I know seem to want that, so sure, gender dysphoria is a psychiatric disorder.”

I agree here with this pragmatic approach. If people feel better after surgery and it relieves their dysphoria there is a good argument for saying that they should be given this treatment. Presumably you also agree with the removal of limbs for those with body integrity identity disorder. Though I think both types of patient should be given a full run down of other psychological causes which may be affecting their beliefs before they can volunteer for surgery removing healthy body parts- having met people who later realised this wanst really the issue at all.

The hair dryer solution seems fair enough. Though if the woman had swapped her anxiety onto the iron and then the curling tongues and the lamps and then the tumble dryer it may not have been quite such a genius stroke. But whilst it was just a hairdryer no harm done. And there was no principle of reality that was being breached-the woman was correct in knowing that the hair dryer could not burn her car down when it wasnt plugged in. I have though another example of such an unusual solution which then created further problems.

I asked my psych nurse friend was it not sometime easier to play along with patients delusions than to constantly fight against them. He gave me an example of a woman who was convinced her house had a flea infestation. Yet no fleas could be found. It caused her great deal of distress and finally a practitioner had the idea of hiring environmental health to go fumigate her house to see if that worked.And it did. The woman was overjoyed to have finally rid herself of the fleas and all was well.

Until a few months later when she became convinced that a new infestation had taken root. She asked again for the fumigators to be called but this time the practitioner declined saying no fleas were present. The woman was really confused and said 'But they were here before, otherwise the fumigators wouldnt have been called to exterminate them' So what seemed a simple fix actually ended up propping up a persons delusion.

"Imagine if we could give depressed people a much higher quality of life merely by giving them cheap natural hormones. I don’t think there’s a psychiatrist in the world who wouldn’t celebrate that as one of the biggest mental health advances in a generation."

Hormones permanently change the body as well as there being as with most drugs, dangerous side effects. It would seem better to investigate drugs which might remedy the dysphoria by addressing the brain issue rather than the body.

"Imagine if we could ameliorate schizophrenia with one safe simple surgery, just snip snip you’re not schizophrenic anymore. Pretty sure that would win all of the Nobel prizes."

This is a very worrying example. For in fact there was such an operation and it may have even got a Nobel prize. It was called the frontal lobotomy and in an age before anti psychotics it was a very useful operations allowing schizophrenic and manic patients to live perfectly peaceable lives no longer confined to the asylums. And it had the bonus of making everyone's life around these people a lot easier. What was then hailed as a wonder cure, a panacea for all mental health ills is now seen as one of the worst psychiatric human rights abuses. You would then think the psyciatric profession would be a little more cautious and less gung ho about the introduction of another surgical procedure claimed as a cure.

"Imagine that we could make a serious dent in bipolar disorder just by calling people different pronouns. I’m pretty sure the entire mental health field would join together in bludgeoning anybody who refused to do that. We would bludgeon them over the head with big books about the side effects of lithium. "

Another very dubious conclusion here. That psychiatrists like some form of modern priests would insist that the population at large lie en masse to prevent a very small percentage of the population from having to take drugs with unpleasant side effects to help their condition by affirming a delusion.

"Sometimes when you make a little effort to be nice to people, even people you might think are weird, really good things happen."

This is really the crux of the article's entire argument. We should do it to be nice. Only where are the rights of other people in this? Why should everyone be forced to endure cognitive dissonance, to lie about their own perceptions of the world in order to humour a small subsection of the population who are unfortunate enough to have what may be a developmental brain glitch or a misapprehension caused by any number of other psychiatric conditions - and where there is no way of knowing which.

It would be salient then if this is considered a good thing, if everyones elses sense of authenticity is expected to be compromised that the potential harms also be considered. What for example if your trans man patient or trans man friend commits a crime and is sent to prison. How do you feel about them being sent to male prison whilst in possession of a vagina. (No surgery is necessary to legally change sex) Much like allowing someone who identified as a wolf into the wolf enclosure at the zoo. Is this not where reality hits abrutly up against niceness? Only this week a trans man was raped in a hostel by a man who didnt much care that she told him she identified as male. Because he percieved her quite correctly, to be female.

This also runs into hot water the other way round. Now male sex offenders can claim they feel like women. Some may be genuine some not. On this basis they can then be moved to female prisons. What of the rights of the women in the prison? Who is being nice to them? Housing a woman in a cell with a serial rapist doesnt seem that fair an idea. Nor does destroying the ability of all women to ever congregate without males, be it in a changing room, a domestic violence centre, a rape crisis centre or any other spaces where women might be vulnerable to sexual assault. Which is statistically carried out far more by males, regardless of how they identify.

This problem with self identification has already been flagged up by gender specialists who state there is a huge rising tide of male sex offenders now identifying as women, most of whose claims they think are false. But of course they will be in no position to decide if self declaration is the only criteria necessary. If it is a psychiatric disorder then its the first one where the patient is allowed to diagnose themselves and demand the treatment of their chosing.

Here we see that yes it is nice to be nice, but sometimes being nice by dint of dishonesty has many unintended consequences which are not quite so nice. Do you think the right to be affirmed as one percieves oneself for 0.3% of the population is more important than the rights to safety for 51% of the population? From a utilitarian perspective it certainly doesnt add up.

"I ought to accept an unexpected man or two deep inside the conceptual boundaries of what would normally be considered female if it’ll save someone’s life. "

The suggestion that we should be hostage to people suicidal threats or attempts is a very morally dubious one. We do not advocate women to stay with men who threaten to kill themselves if they leave or to give into terrorists because otherwise they will blow themselves up. There is a emotional blackmail angle here that in any other circumstance as a psychiatric professional you would surely question.

"There’s no rule of rationality saying that I shouldn’t, and there are plenty of rules of human decency saying that I should."

There are plenty of rules of rationality saying that you shouldnt. And a very restricted version of human decency that you should. One that only flies if you consider the feelings of a tiny fraction of the population to be more important than everyone elses right to safety, freedom of belief and authenticity. Which doesnt seem very decent at all.