A mental illness diagnosis is always political. By this, I do not mean that all distress is equal, or that delusions are merely alternative ways of perceiving reality.

Everyone’s version of truth varies a little, but not all accounts are equally worthy of validation. Some people really don’t see the world as it is, in ways that can harm themselves and others. Even so, not all delusions are viewed as signs of mental illness, and not all people who are labelled “mentally ill” believe things which are untrue. This is where politics comes into it.

To be officially diagnosed as having lost your grip on reality is profoundly disempowering. To be viewed as insane is to be discredited, no matter how much those around you might call for an end to “mental health stigma”. Most people understand this, even if they pretend not to. “Mentally ill” is not a slur when it applies to others, but it is when it is applied to us without our consent.

People like my brother ruin the mental illness marketing campaign

It’s been three decades since my brother was diagnosed with schizophrenia. Since then I’ve always been conscious of the hypocrisies that characterise modern-day “acceptance” of the mentally ill. There’s the embrace of the high-functioning, the gifted and the artistic, versus the evident embarrassment surrounding those who lack any social or cultural capital. People like my brother ruin the mental illness marketing campaign by resembling the very stereotypes the stigma-busters wish to destroy. It’s considered prejudiced to think those with a severe mental illness are like him; therefore people like him are best ignored.

People who might once have been labelled mentally ill, but no longer are, can be less than considerate towards those still languishing in the “mad” box. We know that, historically, part of the function of an “insanity” label has been to stigmatise, alienate and demonise. Behaviours that once met the standard for mental illness have included being gay, wanting to leave your husband or wishing to escape from your slavemaster. We see that applying a mental illness label can be an abuse of power. Less commonly acknowledged, is that this can still be the case even if one is genuinely ill.

This abuse of power has continued well into the “anti-stigma” age. Earlier this year, it was revealed that female members of the armed forces who complained of rape were being diagnosed with personality disorders. Family courts use diagnoses of “parental alienation syndrome” to claim that mothers have turned their children against men accused of abuse. You might think that anyone who has narrowly escaped this kind of treatment would have an acute awareness of how closely the validation or otherwise of your perceptions can relate to your social status. For many, however, it seems to prompt an even greater desire to distance oneself from the “truly” mad.

The idea that being trans is a mental illness comes, according to the group Trans Hub, “from a long history of misunderstanding and miscategorisation”:

Society has long believed people who are different to be sick or ill, and modern human rights movements have fought to correct these myths, such as in 1973, when homosexuality was removed as an illness from the DSM.

You have to admire the half-rightness of this (along with the inevitable piggy-backing on the gay rights movement). Yes, society has long believed people who are different to be mentally ill. The conclusion one ought to draw from this is not that you, personally, cannot be delusional, whereas a load of other people — people like my brother — quite obviously are. It’s that mental illness labels can be as much to do with shaming and isolating as they are to do with caring. The stigma those with schizophrenia and other disorders face is increased by the suggestion that the only problem with the political use of mental illness labels is that they have been applied to the wrong people. If someone like Peter Tatchell really thinks being labelled mentally ill equates to “evil demonisation”, why does he think even genuinely ill people deserve it?

No one has suggested the solution is for the world to play along with him

I am not suggesting there is no such thing as psychosis or paranoia. However, if we are going to acknowledge the relationship between psychiatric labelling and society’s treatment of the marginalised, I will say this: my brother’s paranoia, severe though it has been, has never reached the dizzy heights of believing the women on the Mumsnet feminism talkboards want him dead and that anyone who doesn’t reflect his own perceptions back at him is denying his right to exist. He’s never claimed human beings can change sex, or that JK Rowling is secretly plotting his demise. His delusions are far less extreme. What’s more, those who treat him have never suggested that the solution is for the entire world to play along with him.

This is not because my brother is more or less ill than other people who believe mad things. It’s because he is genuinely marginalised. People who have the power to impose their delusions upon others are not marginalised. They are not like my brother, not because they are more sane, but because the world panders to their delusion rather than label it and then stop caring.

The battle to remove the stigma of a mental illness diagnosis from a select few does nothing to help those who have no power, either because they are delusional in a way that is not socially acceptable, or because they are socially unacceptable in a way that gets labelled delusional. I would like to see a middle ground where we understand that everyone has their own truth, but that some truths are more “out there” (and less true) than others. Psychological distress can be linked to trauma or abuse, not just an inability to perceive the world correctly. I don’t think, “Oh, my brother is providing some deep insight into the nature of being.” I do however think people’s fears and paranoias tend to have some basis in reality.

If being labelled mentally ill is connected to power, then so, too, is not being labelled at all. That’s the imbalance we need to address. Until then, some “mad” people remain utterly isolated, whilst others get to impose their madness on all of us.