SOMETHING very dangerous is starting to happen in this country. Science, our last barrier against irrationality, is under attack. Without science we’ve nothing – no reality, no modernity, no yardstick by which to measure the truth. Without science we’re finished.

If the attacks on science were found only in the online world, then what’s happening wouldn’t be quite so disturbing. The online world is the planet’s psych ward – where the mad, bad and sad go to spew their lunacy into the ether.

However, the assault on science and truth has hopped the barrier between the digital world and taken root in the real world. And it’s not just outsiders, oddballs and cranks who are waging this war against science, right here and right now, in the real world – it’s our political elites.

Two figures stand out this week as real threats to scientific truth, and they straddle both sides of our ever-deepening political divide: Downing Street adviser Andrew Sabisky, with his talk of eugenics and biological racism; and Labour Party frontbencher Dawn Butler with her talk of babies being “born without sex”.

Both are egregious in their own distinct ways, and both are a menace to science and the truth. They represent the mainstreaming of madness.

Sabisky resigned on Monday after a series of disturbing comments he made came to light. “There are excellent reasons to think the very real racial differences in intelligence are significantly – even mostly – genetic in origin,” he wrote. White people are more intelligent than black people, Sabisky suggests.

Sabisky also proposed a form of malignant social engineering, writing: “One way to get around the problems of unplanned pregnancies creating a permanent underclass would be to legally enforce universal uptake of long-term contraception at the onset of puberty.”

Sabisky was hired by Boris Johnson’s increasingly strange chief adviser Dominic Cummings who’d advertised for “misfits and weirdos” to work in Number 10.

Sabisky reanimates a strain of scientific thinking which we thought long buried in our dark past – a time when science was perverted to categorise and grade people, classifying some as worthy and others as not. We know where that ended up in the 20th century.

Thinking such as Sabisky’s is frightening. It’s anti-science, anti-nature, anti-human. Eugenics is voodoo – discredited pseudo-scientific nonsense. It represents cruelty and supremacy. It’s the ultimate dystopia.

But a man with such views got right to the heart of the British government.

Labour MP Dawn Butler sits on the shadow cabinet as the Secretary for Women and Equalities. She’s also running for deputy leader of the party.

Earlier this week, Butler appeared on the TV show Good Morning Britain. In a discussion about the increasingly toxic debate around the issue of trans rights, Butler said: “A child is born without sex.” She added that “a child is formed without sex at the beginning”.

One can support, with all one’s heart, the rights of trans men and women to identify as they wish, to live the lives that make them happy, to love as they please, to be respected and safe, and to be the free and independent people they want to be – without, as Butler did, trashing science.

Sex and gender are not the same thing. Biological sex is in our DNA, it’s written in the Xs and Ys of our chromosomes. Unless you’re waging war on science, then babies – all babies – are born with sex as biology defines it.

Gender is a completely different issue. It’s a social construct. Boys are not born liking football and the colour blue, girls are not born liking princesses and pink – that nonsense is programmed into us by our parents and society.

Gender is like religion. People aren’t born Christians or Muslims, they’re made into Christians or Muslims. Gende, like religion, is a set of opinions handed down to you, or in some cases forced down your throat, by your family, by society, by your country, and by the world.

Gender is an absurdity, a bizarre invention, like money or nationality. No baby is born with ‘gender'. And it would be fine – and good – to say loudly to the world that no baby is born with gender, and that ideas around gender suffocate individuality, personal freedom and happiness. But to say biological sex doesn’t exist is dangerous anti-science, and opens the door to the corrosion of any concept of truth and reality.

I’d go to the stake for the right of another human to define themselves as they wish, but I’d also go to the stake to defend science and reason. The two are not mutually exclusive. Respecting science is not an attack on another person’s individuality or freedom.

Of course, there’s a world of difference between the motives of Sabisky and Butler for their attacks on science. Sabisky seems to favour some sort of dark social pyramid, a hierarchy of human beings, with clever whites seemingly placed at the top; while Butler wants to flatten that pyramid.

But there’s a whiff of totalitarianism about both world views. Science is being co-opted and twisted for political purposes. Sabisky and Butler represent the flight of reason from modern political discourse.

The fall-out from issues like these is always very different for the right and the left. The right will walk away unscathed. Sabisky will soon be forgotten. There will be no internecine warfare. He’s gone. It’s over.

The left, though, loves to split and divide. The left cannot help but destroy itself with purity purges, enemy lists, and circular firing squads.

Put simply: the right thrives on culture war, the left destroys itself. It’s been ever thus. The right uses identity to attract voters, while the left allows identity to repel voters.

The vast majority of citizens know and care little about eugenicist fantasies or the labyrinthine nature of the trans rights debate. But they do know bad science when they see it.

So maybe the anti-scientific extremism we’ve witnessed putting down roots in the political world could have unforeseen, positive consequences. Perhaps, now that we’ve been confronted with such irrationality on both the left and right, we will start to cherish scientific truth a little bit more, to protect it, and search out those who offer intellectual rigour not discredited mumbo-jumbo dressed up as political philosophy.

Neil Mackay is Scotland’s Columnist of the Year