My conversations with Dublin schoolboys suggest that today’s youth find it easier to believe in aliens than in angels. They have watched so many science fiction movies with green men speaking in strange clicks and spits that they presume they must exist. Even one of Mel Gibson’s movies, Signs, in which he stars as an American pastor who has lost his faith, has “true-green” aliens strutting about. Steven Spielberg’s recent remake of War of the Worlds, H.G. Wells’s tale of Martian invasion, features green men set on exterminating us.

Nonetheless, I love science fiction. One of my favourite writers is Arthur C. Clarke, who still produces books though well into his 80s. I have read most of them. A scientist himself, he creates imaginary worlds which appear to be quite coherent. But I was often struck by the thought: “Why are most sci fi writers atheists?” I remember one of his tales, “The Star”, about a priest on a spaceship reconnoitring a scorched planet in a distant galaxy. His faith is shaken when he discovers that a vanished civilisation was incinerated when its sun flared into the supernova which guided the Wise Men to Bethlehem. It was very sceptical and very, very depressing.

In fact, in the worlds of science fiction there are few signs of a transcendent force. The Universe, full of spaceships and alien creatures and far-flung stars seems to have been planted there by itself. Of course, philosophically speaking, this is impossible. Someone had to put the universe there. Even the pre-Christian philosophers Plato and Aristotle knew that.

But Clarke’s views may be evolving. In a more recent story his heroes and heroines are travelling right across the universe in a space ship as big as a continent. The ship is run by “extraterrestrials” whom no one sees or talks with except through robots. It is a closed society like Planet Earth itself, with thousands of people trying to create a harmonious world, all enclosed in an artificial sphere. As far as they can guess, there are other species in the same ship, being observed by these superior intelligences. Like all stories it runs on and on. But the startling element of this story is that some intelligences are beyond what we can see.

This made me return to C.S. Lewis, the literary critic and novelist who became a Christian apologist. In addition to his marvellous Narnia series, he wrote a sci fi novel called Out of the Silent Planet. Mars is inhabited by various groups of aliens, who have not been affected by original sin and live in perfect harmony. It is a little like a modern version of Thomas More’s Utopia and a delight to read. There are few science fiction novels with a Christian background. Tim Powers is one, an American Catholic inspired by C.S. Lewis. Another is the classic A Canticle for Leibowitz, by Walter M. Miller Jr, a 1959 novel about the aftermath of a nuclear holocaust. But there aren’t many others.

These thoughts crystallised recently on reading an article by Stanley Jaki in the Fellowship of Catholic Scholars Quarterly of Winter 2005. Jaki is a well-known philosopher of science and theologian who has written extensively on the boundaries of scientific thought and on the origin and destiny of the Universe. He focuses on the fact that Christ was born in a far corner of the Roman Empire. At that time the known universe was very small. As telescopes were invented, the Universe got bigger. As soon as Galileo found mountains on the moon, fantasy began to take over. Soon people started to speculate about who else might be living in this vast universe -- and whether they were, or could be, Christians. Did Christ redeem them all?

“Underlying all those fears and fantasies about a planet-hopping saviour was the presumption that life was not, indeed could not, be confined to a puny corner of the world even in its intelligent form,”.writes Jaki. He mentions de Fontenelle, writing in 1686 a pseudo-scientific book about a plurality of worlds. It was pure conjecture about the inhabitants of Venus, Mars, Jupiter and Saturn. But even more serious thinkers, like the enormously influential philosopher Emmanuel Kant, were swept away. Twenty-five years before he produced his Critique of Pure Reason in 1781, Kant published a Universal Natural History and Theory of the Heavens. He spoke knowledgeably about Mercurians, Venusians, Martians, Jovians and Saturnians. Even Herschel, the observer of countless galaxies, believed that the Sun was inhabited.

How could such intelligent men believe in such nonsense?  

Jaki argues that they were seeking to replace God. When man does not see himself as a creature of God, then his mind is a mere sparkle in the universe, and there must be millions of species of minds scattered everywhere. Once God is forgotten, Myself comes to the fore, and reason departs into the realm of fantasy. “In his Grammar of Assent where he dealt with various forms of proofs,” the 19th century theologian John Henry Newman  listed this belief in extra terrestrials as “an instance of gratuitous assumption, which as such was useless to argue with.”

In spite of all the radio telescopes and the millions spent by SETI (Search for Extra Terrestrial Intelligence) enthusiasts since Newman’s time, not a single glimmer of any intelligence has echoed back to this planet. There has been no evidence of life anywhere. Every probe shows only signs of dust. There are not even any signs of death. Science tends to support this. In the 2000 book Rare Earth: Rare Earth: Why Complex Life is Uncommon in the Universe, for instance, two professors from the University of Washington in Seattle maintained that even primitive forms of life may be restricted to a narrow corner of our Galaxy.

The most likely scenario, then, is that we are alone in the Universe. There are no little green men and their fantastic machines. This has enormous implications for our collective self-esteem. If we are alone, this unimaginably immense universe was created by a benevolent God so that we could live in a small corner and goggle at the stars. As the new Pope, Benedict XVI, said in his inauguration homily, we have been willed by God, each and everyone of us, and we have the entire universe as a playground all to ourselves. Perhaps it’s selfish of me, but that’s the way I like it. Nonetheless, I’m going to keep on reading the books of Arthur C. Clarke.

Father Walter Macken contributes columns and comment to newspapers in Ireland. He is the son of the Irish novelist and playwright Walter Macken.