Human Engineering for Climate Change. The Controversial Ideas of Bioethicist Matthew Liao

I recently reviewed a viral X post featuring a 2016 video clip of Dr. Matthew Liao (NYU Center for Bioethics) reigniting a public debate about radical proposals to use biomedical interventions to combat climate change. Liao and his coauthors proposed human engineering and biomedical modifications, because “it’s too late to prevent human-induced climate change and people don’t have the willpower to limit their meat consumption.”

In his 2012 paper, ‘Human Engineering and Climate Change’ (published in Ethics, Policy & Environment), Liao and co-authors Anders Sandberg and Rebecca Roache proposed “human engineering” — biomedical modifications to help humans mitigate or adapt to climate change.

We’re Here To Help

Ronald Reagan once famously said that the nine most terrifying words in the English language are: “I’m from the government, and I’m here to help.”

To help humans mitigate or adapt to climate change, Liao proposes that meat consumers be deliberately made allergic to red meat and possibly other foods through genetic modification of ticks and other methods that alter the human immune system. Doing these types of things could “make us physically smaller or reduce our appetite for meat.” It must also be highlighted that zero clinical trials exist on such interventions, not only for climate purposes but also for their long-term effects on the human immune system and their unintended consequences.

Playing God and Dystopian Concerns

The proposal also evokes classic “playing God” concerns: treating evolved human preferences (enjoying nutrient-dense animal foods that sustained our ancestors) as engineering problems rather than features of our biology.

As one examines Liao’s dystopian suggestions, these thought experiments are nothing new. This discussion highlights a deeper tension when so-called experts propose altering fundamental human biology for a desired outcome. Liao’s suggestions are reminiscent of Jonathan Swift’s satirical 1729 essay: A Modest Proposal, suggesting that impoverished Irish families sell their children as food to rich English landlords to alleviate poverty and economic hardship. Let’s remember that Liao earned a doctorate in philosophy from the University of Oxford by focusing on philosophical topics, such as whether children have a right to be loved.

Liao politely frames his ideas as tools that will help ‘willing humans’ to overcome their ‘weakness of will.’ They are assuming that humans have a pathological hyperpalatability to red meat and other such products. In some ways, they are correct, which will be addressed later.

Alpha-gal Syndrome

Liao later referenced alpha-gal syndrome — caused by Lone Star tick bites — as a real-world parallel for meat aversion. Individuals’ immune systems are triggered by the injection of Lone Star tick saliva containing a sugar molecule called alpha-gal, which may induce allergies to red meat. These symptoms are usually mild, but can manifest as severe nausea, anaphylaxis, and other immune system effects. As for the actual problem, it’s really hit or miss. Lone Star tick bites rarely induce red meat allergies – likely well under 1%; admittedly, it’s highly variable and not well studied or established.

Deeper Objections: The human machine is complex

Setting aside Liao’s dystopian paper, it highlights a large, looming problem: America’s addiction to highly processed foods. Liao accurately highlights that humans engage in many unhealthy habits, such as consuming ultra-processed foods (UPF’s), refined carbohydrates, added sugars, and industrial seed oils, which are driving the highest rates of chronic disease, obesity, and insulin resistance ever known.

It’s no secret that America has an addiction to processed fast foods. The United States processes over 25 million chickens per day to satisfy the fast-food industry. These factory-engineered chickens are not, in fact, chickens at all. They are genetically bred to mature in 6-8 weeks, become overweight, and the meat is relatively nutrient-poor. It’s a well-known fact that factory-farmed chickens are raised indoors, seldom see the sun, and a tremendous number die from sickness and disease.

Whereas chickens raised naturally outdoors on regenerative farms are much healthier, better for the environment, and don’t require chemicals to stay alive. The key difference is that the birds are not packed together like canned sardines. Approaches like Joel Salatin’s Polyface Farms dramatically reduce disease pressure and eliminate the need for routine heavy vaccination and antibiotic use. Similar arguments could be made for factory-raised beef versus regenerative pasture-raised beef.

Clinical trials and meta-analyses consistently show that unprocessed red meat has beneficial effects on weight gain, insulin sensitivity, and metabolic health when consumed as part of a whole-food diet. Inducing physical sickness to deter meat consumption misses the mark while ignoring the real dietary villains.

Core Criticisms: Slippery Slopes and Unintended Consequences

Critics argue that even “voluntary” biomedical preference alteration sets a dangerous precedent. History shows that many public health measures, beginning as optional or incentivized (vaccines, smoking restrictions, seatbelts), often evolve into social pressure or mandates. Proposing to engineer human appetites for collective environmental goals raises fears of normalization: today, a helpful patch, tomorrow, subtle coercion under mandated narratives.

Voluntary & Self-Sacrifice

Liao has repeatedly emphasized consent, safety evaluation, opposition to coercion, and that his ideas are voluntary. However, examining Liao’s stated goals, what else is he supposed to say? Non-consent, forced mandates, and that we have no choice but to comply? It’s arguable that Liao’s thinking is magical rather than grounded in reality.

As Dr. Jordan Peterson often teaches, forced change is almost never the right solution. It’s about voluntary self-sacrifice. This biblical idea echoes the Exodus story of Moses and the bronze staff, where the moral of the human psyche never responds well to being forced or mandated. Certainly, there are many things we are forced and mandated to do. But for basic pursuits of happiness, people need the freedom to choose.

In summary

The real question for ideas like Liao’s — is how to separate the wheat from the chaff. It’s obvious he’s attempting to attack a problem, so is there some good to take away from his ideas? The Liao debate serves as a useful case study in bioethics: how far should humanity go to solve collective problems, and who decides? As technology advances, these questions will only become more pressing. Addressing ultra-processed food systems, improving dietary guidelines, and promoting regenerative agriculture would deliver dual benefits for health and emissions — without the ethical hazards of preference engineering.

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