David Weintraub, a professor of astronomy at Vanderbilt University, has a stab at answering this question in his new book, “Religions and Extraterrestrial Life: How Will We Deal With It?” In the book, Weintraub picks through the cosmologies of Islam, Hinduism, Christianity, Buddhism, and Judaism to see what happens when you throw aliens into the mix.

That was a movie. Imagine what would happen if we had real-world proof of the existence of intelligent life on other planets: That would violate whole piles of fundamental religious tenets. For Catholics one big problem would be original sin, which is supposed to have happened right here, in a place called the Garden of Eden, leading to the notion of redemption through Christ. If aliens don’t fit into this story, Christianity turns out to be a pretty provincial affair. How would theologians respond to that? How would any religion?

Ridley Scott’s 2012 film “Prometheus,” which proposed that humans had been genetically engineered by an alien species, did not go down well with the Catholic News Service. “What jumps out is the movie’s rejection of a fundamental tenet of theism, namely, the belief that God created the human race,” a CNS reviewer grumbled, going on to describe the plot as “problematic for viewers of faith.”


Though this might sound like an exotic issue for theologians to address, religious thinkers have in fact been considering it in some form for thousands of years. (There is a similar book out this month by two Vatican astronomers titled “Would You Baptize an Extraterrestrial?”) The issue raises profound questions about the breadth of creation and humans’ relationship to the divine, and, Weintraub finds, would challenge some belief systems significantly more than others.

If a Mars rover turned up evidence of life tomorrow, Weintraub’s research suggests that a wide range of reactions would ensue: Evangelical Christians would recoil; Mormons would rejoice; Jews would basically shrug. All, however, would be compelled to take a very close look at their sacred texts, to see which parts need to be reinterpreted. The harder we look out into space, Weintraub notes, the more urgent this question becomes. “We should prepare,” he says.

Weintraub spoke to Ideas by phone from his office at Vanderbilt.


IDEAS: The belief in extraterrestrials has wavered over the years, from dismissal in Aristotle’s time to acceptance 500 years ago, to dismissal during the 19th century to acceptance now. Is this as far as the pendulum has ever swung to the positive side?

WEINTRAUB: I think we are about as far into positive territory as we’ve ever been. I don’t know if it will swing back again. That may depend on what astronomers discover over the next few decades. If we find that Mars is dead, that other parts of our solar system are void of life, the pendulum may swing the other way.

IDEAS: The debate about whether aliens actually exist seems to boil down to a couple of pithy quotes: Carl Sagan’s “If it is just us, seems like an awful waste of space” on one side, and Enrico Fermi’s skeptical “Where is everybody?” on the other.

WEINTRAUB: Right, and both of those statements reflect strong opinion and complete ignorance. We just don’t know. What’s fascinating to me is that in our lifetime we might find out.

IDEAS: In terms of accepting extraterrestrial life, is there a way to categorize belief systems, to say which kinds would handle the news better than others?

WEINTRAUB: The ones that would have the most difficulty are religions of the book, the sacred word, and it becomes harder if the followers are literalists. For those on the liberal side, who might view things metaphorically, it wouldn’t be such a problem.

IDEAS: Islam is a religion that takes the book rather seriously, and yet is relatively open to the idea.

WEINTRAUB: Well, it depends on what’s written in the book. It just so happens that the Koran has words in it saying extraterrestrials exist. There are instances where you can be literal and accept extraterrestrial life.

IDEAS: Is this question an indication of something bigger—are religions that are open to the idea of alien life generally more tolerant, liberal, flexible?

WEINTRAUB: I’m not sure I want to be the one to answer that. Some religions are clearly open to the idea of modern science, such as Bahá’í Faith. I don’t think we can say that because a religion embraces the idea of aliens it’s open to all progressive ideas, but I suspect we’d probably find a correlation.


IDEAS: I was thinking about how the Hindus have Brahman, the origin of the universe, who transcends description, who is beyond knowledge. Isn’t there a chance that aliens will be so far removed from our experience that we won’t be able to make sense of them?

WEINTRAUB: The question that always comes back at me, from kindergartners to grandparents, is what about life as we don’t know it? What if it doesn’t have eyes or antennae or wiggly legs? What if it’s not chemical based but is a magnetic field? If that’s the case, we’re not even going to know it’s there, so there’s no point in worrying about it.

IDEAS: If proof of alien life were to arise, what’s the worst-case scenario for the least prepared religions? Could some even die out?

WEINTRAUB: I don’t see that happening. Obviously, some religions would need to change the language they use, or even some of the things they claim, like we’re the only intelligent beings in the universe, the only ones made by God. Although you could claim that they are creatures of the devil.

IDEAS: In the end, would this really be any more disruptive to theology than the confirmation that we’re not at the center of the universe, or evolutionary theory, or the Big Bang theory?


WEINTRAUB: In some ways this question scares me, because if we think we are alone in the universe, we are more likely to be better stewards of our planet. If we’re not the focus of God’s attention, maybe it doesn’t matter so much if we mess it up. Anyway, I can’t think of anything bigger than this.

Chris Wright is a writer and editor living in London.