The Nobel committee has awarded this year’s prize in physiology or medicine to Dr. Robert Edwards, a pioneer of in vitro fertilization. Given how long ago this achievement took place, this decision is surely meant to be read partially as a political statement – an implicit rebuke of the right-wing churches that want to deny people the right to exercise control over their own bodies.

And right on cue, the Roman Catholic church stepped in to once again remind us of its existence:

The Vatican-based International Federation of Catholic Medical Associations also expressed its dismay about the Nobel committee’s announcement. Jose Simon Castellvi, the federation’s president, said: “Although IVF has brought happiness to the many couples who have conceived through this process, it has done so at an enormous cost. That cost is the undermining of the dignity of the human person.” A 2008 document on bioethics issued by the Congregation for the Doctrine of the Faith repeated earlier Vatican condemnations of in vitro fertilisation because it separates procreation from the conjugal act in marriage…

Whatever else you can say about them, at least the Catholic hierarchy realizes the implications of their own beliefs. A normal IVF cycle involves the fertilization of multiple eggs, of which only one is usually implanted and the rest discarded – so if a fertilized egg is a person possessing a soul, then fertility clinics would be engaging in destruction of human life akin to abortion. So it makes sense, given their starting premises, that they’d be opposed to that as well. On the other hand, you have to admit that their opposition seems much more perfunctory, compared to the time, energy and effort they spend trying to stop abortion. When was the last time you heard of someone being denied communion for having a test-tube baby, or pro-lifers picketing a fertility clinic?

But regardless, their position is still a ridiculous and irrational superstition. A fertilized egg is not a person, just as an acorn is not an oak tree. Personhood requires sentience, consciousness, thoughts, feelings, and the zygote has none of these. It’s a seed from which those qualities may someday develop, but only if a long and complicated chain of developmental events occurs successfully. If that chain of events doesn’t occur, the zygote has no more chance of becoming a human being than a swab of cheek cells.

In truth, I find the Catholic church’s ranting against IVF more than a little sad and comical. They really haven’t advanced at all since the Dark Ages, and their attempts to interpret the world of the 21st century through the lens of a medieval worldview are pitiably ridiculous. Even after everything we’ve learned about how the mind arises from the brain, and how an intricate genetic program choreographs the development of a ball of cells into a thinking, feeling human being, the Catholic theologians continue to insist that personhood exists solely in virtue of possessing an undetectable supernatural appendage called a soul. This idea is of the same vintage as the belief that the solar system is a set of nested crystalline spheres, and bears just as much correspondence to reality.

But there is one thing about this that’s truly offensive, and that’s the belief – not unique to Catholics, but found among the hierarchs of most religions – that there is only one acceptable way to live, and that they alone are the authorities who know what it is. If anything at all disrespects “the dignity of the human person”, it’s telling people how they must lead their lives – only one kind of birth, one kind of love, one kind of marriage, one kind of death that’s allowable, and that they’re sinful and disordered if they don’t conform.

The true nature of human beings is diversity – diversity in who we love, in how we pledge our commitment, in how we organize our families, in how we react to the slings and arrows of fate – and there is more than one way to lead a healthy, happy, ethical life. As long as religious fundamentalists deny this and try to force all human beings onto the one narrow path they deem permissible, they will deserve only scorn and condemnation.