The discovery of life beyond Earth would be a triumph for science but might wreak havoc on certain religions. Some faiths, such as evangelical Christianity, have long held that we are God’s favorite children and would not easily accommodate the notion that we would have to share the attention; others, such as Roman Catholicism, struggle with thorny questions such as whether aliens have original sin.
Now that researchers have discovered more than 1,500 exoplanets beyond the solar system, the day when scientists detect signs of life on one of them may be near at hand. Given this new urgency, Vanderbilt University astronomer David Weintraub decided to find out what the world’s religions had to say on the question of aliens. In his new book, Religions and Extraterrestrial Life: How Will We Deal with It? (Springer Praxis Books, 2014), Weintraub investigates the implications of life beyond Earth on more than two dozen faiths. Scientific American spoke to him about his findings, including whether Jesus saved the Klingons as well as humanity.
[An edited transcript of the conversation follows.]
Which religion will have the toughest time reconciling aliens with its beliefs?
The ones that have decided that we humans are the sole focus of God’s attention. The religions that see the world through that viewpoint tend to be some of the Christian evangelicals. The Eastern Orthodox Church, a branch of Catholicism, also has that view.
There are some people who claim that if God had created extraterrestrials, then there clearly would be words in the Old and New testaments, which we would have already found, that would have said explicitly that God created extraterrestrials—and since those words don’t exist, there can’t be. Well, there’s nothing in the Old and New testaments that talks about telephones either, and telephones do seem to exist.
Which religions are more open to the idea of alien life?
Asian religions for the most part are easily accommodating. In Buddhism, for example, there are lots of worlds. Reincarnation is an important part of that view of life. I could be reincarnated in principle anywhere in the universe. There’s nothing that says I could only be reincarnated on this planet. For Buddhism, there’s no single holy book, no single holy figure who wrote anything down. There are so many big ideas and so many sacred writings, the volume of ideas is almost limitless. A Buddhist wouldn’t be surprised to find life existing in other places.
You write that the Roman Catholics have a particular issue when it comes to extraterrestrials. What is their viewpoint?
Original sin is an important idea in Roman Catholicism. The idea that Adam and Eve shouldn’t have eaten the apple—they committed a sin and that’s how sin entered the lives of humans. Jesus’s act of dying on the cross was to redeem all humans from that original sin, to allow us to get to heaven.
Let’s say you discover some aliens on some other planets and you decide that you should convert them to Christianity. A reasonable question should be why? If they live on planet Earth, they could be descendants of Adam and Eve but if they are Klingons living on planet whatever, they couldn’t suffer from original sin because they’re not descendants of Adam and Eve. Christianity would make no sense for these creatures, unless our understanding of original sin makes no sense.
Roman Catholic theologians are starting to rethink that in light of the possibility that there could be living beings on other worlds. The idea of original sin may be recast not as sin that comes directly from a literal Garden of Eden and a literal Adam and Eve but that original sin somehow simply exists in the fabric of the universe.
Then you’ve also got to rethink some other ideas. If the redemption by the son of God who was incarnated in human form on the Plains of Galilee 2,000 years ago provides redemption for human beings on Earth, does that also provide salvation for Klingons?
Or does Jesus have to separately visit their planet?
Right. That’s a serious theological problem. Most theologians are pretty seriously averse to the idea that the son of God will have to visit every planet and get crucified on every planet.
What if there’s another planet that’s been in existence for 100 million years before us? Do all of those creatures not get to go to heaven because the Jesus event didn’t happen until 2,000 years ago? Is that fair? It’s not for me to say.
Some Catholic theologians are wiling to wave their hands and say it’s simply not a problem; God will take care of it. Some say it’s a serious problem. But theologically it’s a pretty interesting problem. These questions have been sitting out there for several hundred years. Two hundred years ago [American revolutionary and political philosopher] Thomas Paine put these questions out there very eloquently, and theologians started to address this and decided, yeah, this is a problem.
Do any religions explicitly discuss the possibility of life beyond Earth in scripture?
The middle of the 19th century is when a whole bunch of new religions were born, and many of those religions had something to say about extraterrestrials. In Seventh-Day Adventism, for example, the founder had visions of extraterrestrials—Saturnians—in which she saw them and saw that they were pure; they had not sinned. The only sinful beings in the universe were humans on Earth. That was her solution to the Thomas Paine problem, the original sin problem. The Saturnians didn’t need Christianity because they didn’t suffer original sin.
What about other religions, such as Quakers or Jews?
Quakers don’t really care if there are extraterrestrials. In Judaism it doesn’t matter—there’s very little in Hebrew scripture that relates to the question.
Mormonism is pretty interesting. There is a clear belief in Mormonism in extraterrestrial life. All Mormons have as a goal to become exalted, to become a god. To become a god you effectively get your own planet with your own creatures on it and you’ll take good care of them. The only place in the universe where you have the opportunity to become exalted is Earth. Those Mormons that receive the highest level of exaltation will be equals with God and have their own worlds, occupied with living beings seeking their own salvation and immortality. The prophet Joseph Smith taught that these worlds are or will be inhabited by sentient beings. It is everywhere taken for granted. They’re not vague at all. There’s no doubt that the Mormons are comfortable about the idea that there are others on other worlds. They’d be unhappy if we didn’t find anybody. But they’d just say we haven’t looked hard enough.

From all your research, does it seem like the discovery of extraterrestrial life is likely to have a dramatic effect on people’s religious beliefs?
I can’t think of anything that would be bigger. I think at bottom most people have this idea that we humans are pretty special creatures and that God is paying attention to us. If we find somebody else, then there are lots of somebodies, most likely. And if there are lots of somebodies, that somehow would seem to make us less important. I think that is, psychologically, what has happened a number of times in human history. When Copernicus first said the Earth goes around the sun, theologically that meant we’re not the center of the universe anymore. Later on when astronomers said the sun isn’t the center of the universe, it’s just a silly star out in the suburbs of the galaxy, that threatened our well-being again. Suddenly if there are other beings out there, I think it changes completely the way we think about our place in the universe. I think it would be truly profound to know that.