I refuse to give you the crusty and grumpy Christian case against genetic optimization.
I’m going to grant most of the rationalist utilitarian assumptions and argue that even rational utilitarians aren’t going to like where all of this ends up.
I might be Catholic, sure, but I’m an anarchist Catholic: I don’t care if transhumanists want to pleasure themselves to death. That said, I’ll explain why I lean against IVF and embryo selection, and why I think even secular utilitarians should, too.
Then I’ll argue that if we’re going to genetically optimize our babies—which we may have to, because we are locked into gradient descent for survival—we should wait for direct gene editing in utero, which is consistent with Church teachings if it’s curative.
Genetic Manipulation Is a Race to the Bottom of Market Slavery
At the current juncture, genetic manipulation seems like a free lunch. If you improve your babies compared to babies who are not getting genetic manipulations, you get ahead. But if you play the game forward and everyone is doing genetic manipulation, this is not the progression of liberation and advancement of freedom. It’s submission to whatever few attributes the market requires. Once everyone does this, everyone will have to optimize for a small number of traits just for their kids to have a chance of surviving. In equilibrium, you won’t have options about what to optimize for. Even if PGT and AI continue to improve, market logic invades personal reproduction, forcing parents into competitive escalation.
An Optimization Problem We’re Not Equipped to Solve
On the optimization problem, as human beings, we don’t have defensible frameworks for thinking about which human traits, given trade-offs in the mechanics of the genome, ought to increase or decrease. It’s not even a measurement problem. Even if you assume the genetic testing and manipulation executions are perfect, it’s an epistemological problem. If you don’t see a framework where you can confidently decide what should be increased and decreased, then there’s no good reason to manipulate something with such extreme leverage. Tweaking “good” traits isn’t linear. At life’s extremes, rational models may fail to capture the complicated interplay among multiple genetic qualities, risking distorted outcomes.
Lindy, Faust, Etc.
It’s easy when embryo selection offers the ability to increase your child’s IQ by a few points. It seems simple, but this is a perennial problem of temptation. This fits the Faust story perfectly. It looks like something obviously good with no downsides in the short term. But once you do it and sell your soul, you’re trapped in long-term outcomes you’ll regret. Recall that Faust was a professor type, a wandering scholar. Embryo selection is precisely the kind of temptation historically faced by intellectuals who are dissatisfied and bored with their existence. They need some clever new way to steal power from God, primarily because they’re bored and just want more power. But it always backfires. This teaching is widespread across time and space. Pandora’s Box, take your pick. The Lindy principle suggests that established, time-tested norms are often the wisest choice. I note also that in Goethe’s Faust (1829), Margaret kills her child…
Your Gene Line Won’t Beat the Billionaires
Gene embryo selection feels like a clever way for upper-middle-class people to get ahead. But this upper bourgeois striver mentality won’t have a chance if it gains adoption. If billionaires chose to do it maximally, their kids would completely swamp yours. The only reason billionaires aren’t already swamping our kids is the massive cultural stigma against cold, rational baby maximizing. Elon Musk only has around 14 children, mostly through IVF, and people hate it. He gets constant criticism, and drama from the mothers of his children. That’s not much at all—Elon could be producing 25,000 kids right now, if he wanted to. The only reason he’s not is that our culture says no to this. If you want to promote embryo selection and IVF, you’re removing the only thing shackling billionaires from complete genetic domination of the globe. With around 200 decabillionaires worldwide, if each invested $1 billion into high-throughput IVF programs, each could fund roughly 26,000 or more new births—leading collectively to millions of genetically “curated” offspring.
Here’s the math. Assume our 200 decabillionaires each allocate $1 billion at $15,000 per IVF cycle, and it takes 2-4 cycles to make a baby, this would generate around 26,000 babies and 200,000 discarded embryos per decabillionaire. This results in 5.2-5.3 million total babies across all decabillionaires. There are wide confidence intervals around these figures, of course, but it’s something like this.
If those babies then also use IVF disproportionately, the lineages of these 200 decabillionaires today would quite quickly become the vast majority of all people who live into the future.
Forget all your dreams about “populating the solar system.” A human species may do so, but it will not be your species. With IVF saturation, you and your bloodline are gone. Unless you happen to be a billionaire with a procreative drive that would make Genghis Khan blush.
If You Care About Shrimp Welfare, You Should Care About the Coming Embryo Holocaust
The potential number of discarded embryos in a world where IVF and embryo selection become popular is startling. As a Catholic, I believe life begins at conception. But even if you don’t, you must grant it some non-zero value, some slight positive direction on the path towards sentience. Even if you say it’s purely material physical value, the universe has structured matter in a negentropic fashion to create order from chaos. To account for this, you need to do basic math about how many embryos will be discarded and the total value destroyed. In basic numerical exercises, we could be discarding possibly a billion embryos a year globally, which is at least 200,000 human lives even with materialist assumptions about embryonic value.
Here’s my slightly expanded math using point estimates. If the cost of IVF and embryo selection continues to decrease and this technology reaches mass adoption, it would be sometime in the mid-to-late 21st century that 90% of global births could be IVF. At this point, the world would discard on the order of 1 billion embryos each year. If we assume conservatively that discarding a day-5 embryo equals 0.0002 of a human life (~30,000 days in a full life), this would be about 217,000 human lives lost annually—comparable to ~73 “September 11” events per year.
Here’s the math using full ranges from the multiple empirical estimates I gathered. These things are hard to measure so different sources/models (Grok, OpenAI, and DeepSeek) will give you different estimates. If IVF costs continue to decline from current levels of $20,000-$40,000 per baby, at rates of 5-10% annually, then we’d expect to see 90% adoption somewhere between 2050-2144. This would mean anywhere between 301.5 million to 2.5 billion discarded embryos annually. With a global population at that time between 11.1 and 18.9 billion, producing 120-354 million total births (108-319 million via IVF), and 2-8 discarded embryos per IVF birth, this will result in somehwere between 51,557 and 510,000 human lives lost yearly—and that’s assuming you’re a secular, rationalist atheist who does not believe an embryo is a human life! That’s equivalent to the 9/11 terrorist attack happening 17-170 per year.
Wait for In-Utero Gene Editing
In contrast to pre-implantation selection, in-utero gene editing for clear therapeutic goals seems more ethically defensible. They’ve done this with mice; we should have this technology soon enough. Healing or preventing disease through gene manipulation is welcomed by the Church, even though cosmetic enhancements are not. Christians will still get super-babies with technology, and my wager is that the restriction against creative enhancement will practically outperform in the long-run, given the optimization problem we’re not equipped to solve.