Anyway, the usual boring straitlaced prudes on Twitter got on her case about it. And the poor woman became that day’s Twitter sacrificial lamb, or foal. “Yup, that bestiality tweet was a mistake,” she tweeted later on, sadly, having deleted the original. “I’ll never talk about it again.”

It was interesting, because at one point she made a pretty unanswerable point: unless you’re a vegetarian, you haven’t really got a leg to stand on here. “The fact is,” she said, “you’re being inconsistent if you’re fine with killing and eating non-human animals while opposing sex with non-human animals. They didn’t consent to being killed and eaten yet you’re perfectly fine with it.”

Jonathan Haidt, in his book The Righteous Mind, talks about a phenomenon called “moral dumbfounding”. That is: when something is disgusting, and you want to say that it’s immoral, but you can’t think of a reason why it’s immoral. So you end up simply saying it just is. One example he gives is of a man going to the shops and buying an oven-ready chicken. That evening, before cooking it, he has sex with it. Then he cooks it and eats it. Is that immoral? Apologies if you’re having chicken for dinner, by the way.

Most of us want to say yes, it is immoral. But most of us – especially those of us in the West, and on the left-liberal side of politics – think of morality in terms of whether someone is harmed, oppressed or cheated. And when you’re making love to a dead chicken and then eating it – who is harmed? The chicken? You feel that as far as the chicken is concerned, the worst has already happened. The man eats the chicken himself, so he’s not inflicting violated chicken on anyone – and it’s properly cooked, so no risk of diseases! Who is the victim here?

Disgust is a moral emotion. (I can feel my wife’s moral disapproval when I put mayonnaise on pizza.) But we have, in the West, somewhat separated our sense of morality from our sense of disgust. It is not enough to say “that is wrong because it is disgusting”: you have to say “it is wrong because of [these reasons], and the fact that I am also disgusted by it is an entirely separate and coincidental thing.” 

In the case of the woman fantasising about the horse, the responders were saying things like “It’s wrong because of a lack of consent” or “we evolved to eat other animals”. They were trying to find reasons other than that is disgusting. But those reasons don’t stand up: she had already stipulated that the horse was willing – the horse had consented. That’s right there in the premise of the thought experiment. It’s a fantasy: if horses can’t consent, then she won’t shag one. (Philosophers need to live in the Least Convenient Possible World!)

And the “we evolved to eat them” argument is a straightforward case of the naturalistic fallacy. You can’t get an ought from an is – just because something is natural doesn’t make it right. However you look at it, one suspects that the horse would rather be allowed to have sex with a woman if it chose to, than be chopped up and put in Tesco beefburgers. 

The trouble is that following our moral reasoning all the way through is often extremely uncomfortable. In the case of a woman tweeting fantasies about sex with a horse, it’s merely funny; but in other cases, it leads us into genuinely difficult areas.

For instance, Richard Dawkins recently got in trouble for saying on a radio programme that aborting foetuses at risk of various disabilities, including Down’s syndrome, was morally acceptable: he said that it might plausibly “increase the amount of happiness in the world”.

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I should specify that he was rowing back an earlier comment, from 2014, that it was immoral not to terminate those pregnancies; but again, it hits some deeply uncomfortable note, and we want to say this is immoral. We picture a real child with learning disabilities; we hear from parents of children with those disabilities. We are outraged and disgusted.

But if we are pro-choice, as I am, then Dawkins’ position is implicit. Abortion is already legal in cases of likely foetal abnormality, and 90% of prenatal diagnoses of Down’s lead to termination. It is the woman’s choice, of course: but their choice is presumably made on the basis that either they expect the child would not lead a fulfilling life, or that they expect the cost to their own wellbeing and happiness would be too great. And we (those of us who are pro-choice, anyway) already agree with that. Dawkins merely said the quiet part out loud.

Our visceral reactions drive our moral decisions far more than we might want to admit: for Haidt, the reasoning part of us is usually just coming up with socially acceptable justifications for our emotional gut reactions, a presidential press secretary rather than a policymaker. (As the Matt Hancock scandal was breaking, a friend got in touch to say that he thought a lot of the reason why people were so appalled was because they were sexually disgusted at the idea of being kissed by Matt Hancock, and the rest of it flowed from there.)

According to Haidt, many non-Western or non-liberal people find it easier to say why things that disgust them are immoral: they have a wider sense of what is moral than just “does it harm people?” or “is it fair?” They might appeal to traditions (“not shagging horses was good enough for my father, and his father before him!”) or the disapproval of the community, or simply say this is not what is done. 

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But Western liberals – or more accurately, members of the group known as Western, Educated, Industrialised, Rich, Democratic, WEIRD – need to rationalise out their disgust. Leon Kass, the philosopher, argued in 1997 that we have lost something as a result: that disgust should guide our moral judgments. People getting disgusted at the cloning of Dolly the Sheep or other technological efforts to play god, he says, are “warning us not to transgress what is unspeakably profound … Shallow are the souls that have forgotten how to shudder.” 

And remember, Haidt says that WEIRD liberals tend to think of morality in terms of whether someone is harmed, and in terms of fairness, while non-WEIRD people and non-liberals are more likely to care about other concerns — authority, sanctity and loyalty. And he thinks that liberals should be willing to adopt those broader moral “tastes”: that if, for instance, liberal politicians want to win more votes, they will need to be able to talk to voters in those terms. For instance, they might want to appeal to the moral tastes of authority and loyalty by talking about patriotism; or they might want to appeal to a moral taste of sanctity by imposing strict penalties on sex offenders.

Haidt may be right on the practical aspect, but Kass is wrong on the moral front. We are sometimes disgusted by things that are immoral – but often we are not. People used to be disgusted by same-sex relationships or interracial marriage; most of us are now not. The disgust response was, in some sense, wrong. The work of moral philosophy is to work out, as dispassionately as possible, what is wrong and what is right: it is a difficult task, but not a completely fruitless one, in that most of us would agree that we have made moral progress in some sense over the last few millennia. 

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You're more biased than you think

By Stuart Ritchie

Emotions like disgust can call our attention to things — we feel disgusted when someone laughs at a homeless person – but they are not reliable guides to what is and isn’t moral. It is worth understanding what drives moral decisions – to understand that some people are disgusted or outraged by things that we don’t, intellectually, think are immoral – but that doesn’t make those moral decisions correct. I can have mayonnaise on my god-damn pizza. You can shag that oven-ready chicken, if you want, although I wouldn’t tell the neighbours. 

And the fact that we are usually not disgusted by the systematic breeding and killing of animals for our food, and yet we are disgusted by the idea of a woman having sex with a consenting horse, is not necessarily a useful way of finding out which is actually more immoral. 

In fact, I will go on record here and say that, yes, morally, it is worse to have animals tortured and eaten than it is to allow them to have sex with you. I’m a hypocrite on this — I do the former most weeks, and the latter only at birthdays and Christmases — but still, I think it is true.

We should welcome the fact that the issue of inequality has surged up the political agenda, given the lingering injustices around class, colour or gender that confront many people in our society. Yet the most powerless minority, a group offered the fewest opportunities and subjected to the worst abuses, remains excluded even in the debate on diversity and inequality.

People with learning disabilities lose out from birth and are largely shunned by wider society. All too often these citizens struggle to access basic services, are excluded from schools, placed in poor housing, suffer routine abuse in the streets, and rarely get decent jobs. It is permissible for comedians to mock them and still be given plum BBC shows, while scientists are rushing into a new age of eugenics based on scans and tests to eliminate conditions such as Down’s Syndrome with scarcely a murmur about ethics.

As the father of a daughter with profound learning disabilities, I find this highly depressing. It has inspired my campaign to highlight the scandal that people with autism and learning disabilities are being incarcerated in secure hospital units for years on end by the state, often in hideous conditions behind locked doors, in solitary confinement and sometimes even with families silenced with gagging orders or through intimidation. Incredibly, the inequality inflicted on this exiled minority even includes death.

Further reading

The invisibility of disability on screen

By Ian Birrell

It is estimated that 1,200 people with learning disabilities die avoidable deaths in the national health service each year. That is 100 needless deaths of people like my daughter each month – or more than three every day. Little wonder that women with learning disabilities die 27 years earlier than other British females and men 23 years earlier than the rest of the population. Sometimes this is due to dysfunctional services or unintentional lack of understanding, which is bad enough. But there are also cases of prejudiced professionals participating in a slaughter of innocents.

This shameful situation was confirmed by the Learning Disabilities Mortality Review (LeDeR), after Sara Ryan, a medical researcher, spoke out following the death of her teenage son Connor Sparrowhawk due to failures by Southern Health Trust. He was left to drown in a bath after suffering an epileptic fit, despite his carers’ full knowledge of his condition. The latest LeDeR report found about one in 12 of fatalities investigated ‘received care that fell so far below expected good practice that it either significantly impacted on their well-being or directly contributed to their death’. Concerns had been raised in more than one in 10 deaths.

Pneumonia, a treatable condition, was often a cause of death. The review found bias continues even after death, with cases significantly less likely to be reported to a coroner. Down’s Syndrome is listed routinely as a reason not to resuscitate, while learning disabilities appear as ’cause of death’ on medical certificates, although it is not a disease that can kill like cancer. This highlights how even some health professionals in hospitals disregard people with learning disabilities, reflecting wider prejudices that corrode our society.

Further reading

Under-reported: The issue that terrifies politicians and affects every household - social care

By Julia Unwin

Imagine the outcry if another minority was dying due to blinkered attitudes in the sacred NHS. But for bereaved families of the disabled, their misery is compounded by a struggle to have the truth heard. Take the case of Jack Adcock, a six-year-old boy with Down’s Syndrome who died due to errors made by a registrar called Hadiza Bawa-Garba in 2011. His parents suspect special needs were a factor in the neglect leading to his death. But when the doctor was struck off, there was an outcry among fellow medics leading to a long-running, crowdfunded legal case backing her – not anger over a small boy who should still be alive.

When the first LeDeR report was released last year, the health secretary did not even bother with a statement in parliament. Then the second review was ‘buried’ in the same week as two other reports into the autism scandal before a devastating BBC Panorama expose of abuse. This reduced embarrassment for the NHS and ensured Matt Hancock could clear the decks of discomforts before the launch of his Tory leadership bid. “It is worse than doing nothing,” said Ryan. “People are dying in total breach of human rights, but these people just give a pretence of doing something.”

She is right. This work by Bristol University to review more than 4,300 deaths over the past three years should be taken out of NHS hands and placed under an independent body that will not bend easily to political winds.

Further reading

Our shameful social care crisis

By James Bloodworth

It is, of course, far easier for politicians to praise the NHS or pose as its protector from foreign invasion than to fight for the rights of vulnerable people falling victim to its failures.

From Westminster to our hospitals, we see clearly the gross inequality that confronts Britain’s most excluded minority and stains our society. What other group could be confined in secure psychiatric units and forcibly drugged with fewer rights than child killers amid minimal public concern? This systemic disregard is made worse as some bear the brunt of local authority spending cuts that slash support and entrench their isolation.

Now we know that people are dying from indifference in a health system supposed to offer sanctuary. And the ultimate tragedy is how few people really seem to care.

To read the rest of the Riven Britain series, click here.