Factory farming is the cruel industrial revolution of the last half-century, I’ve discovered from Jonathan Safran Foer’s Eating Animals (2008). Over 99% of all farming in the rich world has, quite suddenly, become industrial. House prices and car prices have increased 14 or 15 times, but chicken prices have barely doubled. We now eat cheaply what we most want to eat: meat.

We all know the factor of adjustment. It is the animals.

To make cheap bacon, sows are imprisoned in body-sized crates. To make cheap beef, slaughtered cows are bled while still alive – legally, since the food industry wrote the ambiguous law. Above all, billions of industrial chickens lead lives of pure misery and suffering, from beginning to awful end. Modern broiler chickens live for 5 or 6 weeks, in darkness, barely able to move, kept alive by antibiotics – the least costly solution – before being tossed into a crate for slaughter. A large fraction of them do not die at the official instant of slaughter, but rather before and after it, presumably in terrible pain. Most male chicks of laying chickens, by definition superfluous to demand, are simply pulped at birth, literally. At every stage of these processes, animals risk additional cruelty by the overworked humans processing them. Cruelty, systematic and gratuitous, is what made possible this industrial revolution.

But cruelty is not the only unpriced externality of factory farming. There is also the cost to public health. In the USA farmed animals produce 130 times more waste than humans, without the benefit of a sewage system. Inside factory sheds and slaughterhouses, pollution and pathogens can only be controlled by antibiotics, an aberrant situation which undermines humanity’s defences against future disease pandemics.

Most of all, industrial meat farming is an environmental disaster. Instead of feeding people directly, most agricultural crops in the rich world are fed to animals. The industry consumes vast quantities of often-precious water, and land which could otherwise be wilderness. And it emits more carbon than all transport.

Factory farming is thus completely unsustainable in a world of 9 billion. The Earth will eventually “shake it off like a dog shakes off fleas”, says Jonathan Safran Foer. Until then, the industrial-scale pollution and suffering go on.

What does the author advocate? Selective omnivory, perhaps: he quotes non-factory farmers, who believe that “humans can provide animals with a better life and death than they could hope for in the wild”. Vegetarianism, maybe: eating meat is perhaps compatible with animal welfare, but not with animal rights. Refusing meat is also a pragmatic answer to the real-world scarcity of non-factory produce. Ultimately veganism is the least ambiguous response.

But Jonathan Safran Foer advocates none of these things. He just wants a public debate. The meat industry, which keeps its factories locked down against camera-wielding intruders, did not even respond to his terrible accusations. It does not want that debate, and neither do we.

Humans are incoherent to the point of schizophrenia. The factory farmer claims that “family farms will not sustain a world of ten billion” – but that is an excellent argument for vegetarianism. The traditional farmer raises animals as a commercial endeavor, but claims not to regard his animals as a commodity. And we consumers are the most egregious hypocrites of all. We pamper our pets and idealize nature, while martyrising our farm animals and despoiling the environment. We are outraged by the idea of animal cruelty, but continue to pay for it daily.

Factory farming is an excellent challenge to our moral integrity, since almost nobody is asking us to do the right thing. “Do you eat chicken because you know the science and have decided their suffering is acceptable, or because it tastes good?”, asks Jonathan Safran Foer. The question is horribly easy to answer.