Man’s attitude toward nature is today critically important simply because we have now acquired a fateful power to alter and destroy nature. But man is a part of nature, and his war against nature is inevitably a war against himself.

[We are] challenged as mankind has never been challenged before to prove our maturity and our mastery, not of nature, but of ourselves.

—Rachael Carson, 1964

By Stephen Best
June 2024

When we kill animals, we kill ourselves. That is not exaggeration. That’s science. We usually don’t drop dead on the spot, but most of us, tragically, do die slowly and much sooner than we might like, mostly because we kill animals. 1

Given killing animals is killing us, maybe giving the killing some thought is a good idea? How about a thought experiment? Risk free, costs nothing. Let’s ask, what would the world be like—more importantly for most people, what would we be like—after we let animals live?

The elephant in our mental lab, however, is most people don’t care much about the animals with whom we share this planet. Most people, especially in the planet’s posher parts, barely think about animals unless they’re filling their pets’ food and water bowls, changing their litter or taking them out for a walk and to relieve themselves.
So, what’s the point of this thought experiment? Why would people care? The point is ‘don’t care’ is killing people. “Killing people?” That’s an understatement. Mass killing people is more accurate. And, like the mythical boiled frog, most people don’t even notice they’re being killed, although they might care if they knew. Had they noticed and cared, most—yes, most—could have saved their lives or limbs, if living or limbs were more important than continuing to do what was killing them, which is usually not the case.

To jump start getting over the bar of, if not caring, at least noticing, consider that,

“Even if fossil fuel emissions were immediately halted, global protein production alone would make meeting the Paris Agreement’s 1.5°C target impossible.”2

“…animal agriculture is the leading cause of climate change, responsible for 87% of greenhouse gas emissions. The burning of fossil fuels is currently the leading source of human-made carbon dioxide (CO2) emissions. However, climate change is caused by cumulative human-made greenhouse gas and aerosol emissions and not just current CO2 emissions alone. While humans have been burning fossil fuels for a little over 200 years, we have been burning down forests for animal agriculture for well over 8,000 years…the transition to a global plant-based economy has the potential to sequester over 2000 Giga tons (Gt) of CO2 in regenerating soils and vegetation, returning atmospheric greenhouse gas levels to the ‘safe zone’ of under 350 parts per million (ppm) of CO2 equivalent, while restoring the biodiversity of the planet and healing its climate.” 3

“Global protein production” is science‑speak for killing animals. The ‘for Dummies’ take-home? We can’t cool down climate heating, i.e. keeping heating below 1.5C, if people keep killing animals.

If every country reduced its climate heating GHG emissions from fossil fuels to zero, but did not address animal agriculture and commercial fisheries, industries whose animal killing is measured in billions and tons, the rate of increase of climate heating would be slowed, but not reversed. 4

Every nations’ political leaders who are not wilfully deaf and blind to facts and reality have this information. So how many are implementing policies and legislation to reduce the consumption of animal-based foods? None. How many subsidize animal-based foods to protect and profit powerful political constituencies? All.

Given the well-understood, catastrophic consequences of killing animals, here’s an odd omission in humanity’s intellectual canon. Millennia of past artistic, philosophical, academic, and scientific musings about human beings’ relationships with non-human animals does not include anything substantive about what the human/animal relationship would be like if people did not kill other animals.

However inconvenient, it is an omission that should, perhaps, be rectified for reasons relating to human well-being, environmental security, and ethics.

Killing animals has been shaping human culture and likely evolution for “at least 2.6 million years.” 5 The anthropological, historical, artistic, and academic human record of the human/animal relationship is global and, at least, 45,500 years long.6 Yet the record includes only a few accidental hints 7 about what a non-lethal human/animal relationship might be like.

The record of the harm done by humans killing animals is extensive, scientifically robust, and indisputable. Who does not recall a David (Suzuki or Attenborough) warning about a species in lock step to extinction saying, “something must done”? Our animal killing record depressingly details and quantifies a range of local and global, very nasty, avoidable impacts to the environment, animals, human health, and even human mental health. It’s not obvious what it all means, at first, because it’s never contrasted with the necessary experimental control: what the world would be like if we let animals live?

Killing lifeforms always has consequences for victim and perpetrator. In the predator/prey relationship it’s the predator who usually fares worse. As predators consume their prey there’s less and less food to sustain them or provide the energy they need to even find their food. Predator populations plummet faster than their prey’s.

So, to better appreciate why this thought experiment is worth doing, let’s use a human scale to first look at people’s impact on animals’ lives. World War II takes the gold as humankind’s deadliest conflict. Between September 1, 1939, and September 2, 1945, people killed about 85 million of their own. 8 And, as in most wars, most of those whom they killed were non-belligerents fleeing the carnage. Eight-five million! That’s how many people live in Germany. It’s twice Canada’s population. And for our thought experimental purposes, eighty-five million is also the number of land animals people kill, globally, everyday between breakfast and lunch. 9

It’s reasonable to wonder, then, what would happen if people, every year, didn’t kill over 150 billion terrestrial animals—wild and domestic? To up the accuracy of our wondering, let’s add the 18 times more marine animals people kill annually, 2.7 trillion. 10

How many of those animals did people need—not just want—to kill for food, clothing, safety, research, self-defence, amusement, or just because they were a nuisance? Not zero, but close to. People rarely kill animals because they need to. They kill animals because they want to.

Because people kill animals mostly to satisfy personal choices, not needs. People could make different choices about killing animals, and they have in some areas. Fur fashion, for example, is declining because people are making different clothing choices. 11

It’s worth asking, then, for at least, four reasons what would it be like after we let animals live? One, killing animals harms people as much as—and usually more than—it does non-human animals. Killing animals has consequences beyond people’s immediate gratification. Two, we don’t need to kill animals for any reason except, perhaps, occasionally in self-defence. And, three, we can, in theory, stop killing them. We choose to kill animals; we do not need to kill them, except in the rarest of events.

The fourth reason? Sometimes, we become better people when we understand the consequences of our choices. Understanding is necessary to start.

First, let’s get real. Is it a possibility that people would ever stop killing animals? Of course not. Don’t be silly. Even when it’s in their own best interest, human beings don’t stop waging genocidal war on their own kind: something they’ve done continuously and globally, according to the archeological and historical record, since, at least, the Epipaleolithic, 13,000 to 14,000 years ago down to the moment when anyone reads the last word in this sentence. Waging war is as biologically unique to the human animal as is making art. Given how eager and predisposed Homo sapiens is to kill 12 can we really expect us to extend compassion to cod and chickens?

Surely, impossibility ought not be a barrier to a cost-free thought experiment which might reveal useful insights. This one might. What’s to lose by running it? Only a little ignorance.

Fair warning, when this thought experiment was floated in casual social settings, most people were unable to do it. This held equally true for sport hunters and anglers and animal rights advocates and their sympathizers, high school dropouts and university professors. Few could get past their self-interested special pleadings to even begin considering a world where people let animals live. A documentary filmmaker was caught up predicting the demise of indigenous peoples’ cultures if they didn’t kill animals. A choir director complained their digestive system was so sensitive they could only eat meat. A rural planner worried about farmers’ livelihoods. An ardent animal rights advocate feared for the welfare and fate of the animals now being farmed when their cages were opened, and they were let free into the wild and the cities.

It was as if they’d missed ‘thought’ in thought experiment.

Even when the thought experiment was amended to ban special pleading by asking unwitting, but game, test subjects to imagine that a half century ago—for reasons not quite remembered—humanity stopped killing animals, and then asking, ‘what is our world like today?’ minds choked, stalled, and sputtered. I wonder, are some thought experiments simply unimaginable? Just culturally, and emotionally too, too hard?

Dammit, let’s explore strange new worlds; seek out new life and new civilizations; boldly go where no man has gone before! Engage.

We begin our thought experiment by establishing what is meant by ‘not killing animals.’ What? First thought might be how odd to have to define what not killing animals means. Not so. Someone asked, ‘does that include not eating eggs?’ Another said ‘can I still have honey?’ A third wondered about oysters. A fourth, ‘road kill?’ To get on with the experiment, let’s stipulate that animals are lifeforms included in the biology kingdom Animalia.

So, ‘after we let animals live’ means not killing, directly or indirectly, lifeforms classified Animalia. If some still want to pedantly quibble or special plead to avoid doing the experiment, they can plug their thoughts into it, turn their mental crank, and see what findings and conclusions their mind spits out.

Meanwhile, let’s assume it’s been two generations since humankind (It’s a miracle!) said, “let animals live!” Two obvious results are, one, the ocean (there’s only one) is teeming with life, because now 100% of it is protected from human predation rather than today’s just 7.7% 13 And, two, 75% of the land once used for agriculture is being put to other uses, and most of it has been left to return to the wild. 14 15

The planet is prettier to most people’s eye, climate heating has been effectively halted, and the parts per million of CO2 in the atmosphere has dropped and is continuing to do so. Letting animals live has meant there are more green plants—land and sea—and they’re feasting on the carbon dioxide in the air. It’s still hot, and extreme weather events means most people still can’t buy insurance, but the light at the end of the tunnel is no longer coming from a burning fuse.

A short digression to revisit omissions: omitted from the Canadian government’s “Canada and the Sustainable Development Goals” 16 is any mention of the necessity to address the fatal effects of animal agriculture on the government’s climate heating an do other development goals. 17

Not only is the planet healing, so too are people. We know that “consuming healthy plant-based foods is associated with lower all-cause mortality.” 18 Because the shift to diets that eschew animals results in healthier people, there’s a massive drop, obviously, in health care costs. “Plant-based diets that are in line with standard dietary guidelines could reduce global mortality by 6–10%. [The estimate is that] the economic benefits of improving diets [would] be 1-31 trillion US dollars, which is equivalent to 0.4–13% of global gross domestic product (GDP) in 2050.” 19

After we let animals live, however, all would not be Babe and Bambi with the animals. Everyone who’s been to a conservation area or park, where dogs are not allowed, knows that animals soon learn that people are not a threat. They no longer flee when people appear. People would need to adjust their behaviour and give animals space and respect not only for the animals’ sake, but also for their own safety. A person alone is ill prepared to fend off feral pigs, a rutting deer, or a mother black bear with cubs about. If you go into the woods today, after we let animals live, you’re sure of a big surprise.

The rural planner mentioned earlier who was worried about farmers’ livelihoods was on the mark. After we animals live there would be widespread and extreme economic change.

“In 2022, [in Canada] animal agriculture directly generated $89.5 billion in sales: $33.6 B from livestock farm cash receipts, and $55.9 B from meat, poultry, egg and dairy product manufacturing. It employed over 164,000 people and generated GDP of $14.7 billion. If the indirect and induced multiplier effects of this economic activity are added, animal agriculture contributed another $32.4 billion in GDP and a further 394,000 jobs.” 20 After we let animals live, that economic activity would end, and the people affected would be forced to change.

Commercial fisheries, too, would come to an end when we let animals live. “Global fish production…reached about 179 million tonnes in 2018, with a total first sale value estimated at USD 401 billion, of which 82 million tonnes, valued at USD 250 billion, came from aquaculture production.” 21 US$401 billion means a lot of working people: “59.51 million…in the primary sector of fisheries and aquaculture, 14 percent of them women. In total, about 20.53 million people were employed in aquaculture and 38.98 million in fisheries.” 22

The activities affecting climate heating, human health, and environmental degradation are usually due to human economic activity. It’s not possible to deal successfully with any issue plaguing humankind without changing economic activities. That always changes people’s lives no matter if they’re New York cardiac surgeons or Oceania subsistence, artisan fishers. Human activity is the economy. If the Economy is sacrosanct, as many of our most privileged and their acolytes work very hard and invest much money to make us believe, all is lost.

This particular thought experiment merely teases what happens after we let animals live. So pervasive is the effect of killing animals, no area of human activity is unaffected and yet so unnoticed.

From Mr. Wizard to the Myth Busters, we’ve been warned not to do their experiments at home, not so with the After We Let Animals Live thought experiment. Do it at home. Let the animals live. See what happens. Risk free, costs nothing.

References

1 Papier, K., Fensom, G.K., Knuppel, A. et al. Meat consumption and risk of 25 common conditions: outcome-wide analyses in 475,000 men and women in the UK Biobank study. BMC Med 19, 53 (2021). https://doi.org/10.1186/s12916-021-01922-9 https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-021-01922-9

2 Clark, MA, et al. Global food system emissions could preclude achieving the 1.5° and 2°C climate change targets (Science 2020).

3 Sailesh Rao, Animal Agriculture is the Leading Cause of Climate Change—a Position Paper, Journal of Ecological Society, Vol. 32-33, (2020-2021), pp. 155-167

4 A global protein transition is necessary to keep warming below 1.5°C, Good Food Institute, accessed January 31, 2023, https://gfi.org/resource/a-global-protein-transition-is-necessary-to-keep-warming-below-1-5c/

5 Pobiner, B. (2013) Evidence for Meat-Eating by Early Humans. Nature Education Knowledge 4(6):1, accessed January 20, 2023, https://www.nature.com/scitable/knowledge/library/evidence-for-meat-eating-by-early-humans-103874273/

6 Adam Brumm, et al., Oldest cave art found in Sulawesi (Science Advances Vol, No. 3 January 13, 2021 DOI: 10.1126/sciadv.abd4648), accessed January 21, 2023, https://www.science.org/doi/10.1126/sciadv.abd4648

12 Dominic Johnson, Bradley A. Thayer (2014) – What Our Primate Relatives Say About War https://nationalinterest.org/commentary/what-our-primate-relatives-say-about-war-7996

13 Hannah Ritchie and Max Roser (2021) – Fish and Overfishing, Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/fish-and-overfishing‘ [Online Resource]

14 Hannah Ritchie (2021) – If the world adopted a plant-based diet, we would reduce global agricultural land use from 4 to 1 billion hectares, Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/land-use-diets‘ [Online Resource]

15 We sold everything off, even the semen flasks’: the film about the farming couple who struck gold by rewilding
https://www.theguardian.com/artanddesign/article/2024/jun/06/semen-flasks-farming-couple-rewilding-knepp-isabella-tree

17 Adam Clasky and Stephen Best, A Fatal Omission, Animal Protection Party of Canada’s submission to the Canadian federal government’s Achieving a Sustainable Future. https://www.animalprotectionparty.ca/wp-content/uploads/2022/08/APPC-Sustainable-Development-submission.pdf

18 Keaver L, Ruan M, Chen F, Du M, Ding C, Wang J, Shan Z, Liu J, Zhang FF. Plant- and animal-based diet quality and mortality among US adults: a cohort study. Br J Nutr. 2021 Jun 28;125(12):1405-1415. doi: 10.1017/S0007114520003670. Epub 2020 Sep 18. PMID: 32943123; PMCID: PMC8547553.

19 Marco Springmann, H. Charles J. Godfray, Mike Rayner, and Peter Scarborough, Analysis and valuation of the health and climate change cobenefits of dietary change, Proceedings of the National Academy of Sciences (PNAS), March 21, 2016

20 Al Mussel, Angèle Poirier, and Margaret Zafiriou, Forces Impacting Animal Agriculture in Canada: A Synthesis, Canadian Agri-Food Policy Institute, November 2023, https://capi-icpa.ca/wp-content/uploads/2023/11/Forces-Impacting-Animal-Agriculture-in-Canada-A-Synthesis-1.pdf

21 FAO. 2020. The State of World Fisheries and Aquaculture 2020. Sustainability in action. Rome. https://doi.org/10.4060/ca9229en, http://www.fao.org/3/ca9229en/ca9229en.pdf

22 Ibid