This question is based on what I call, tongue in cheek, "Shermer's Last Law," that any sufficiently advanced extra-terrestrial intelligence is indistinguishable from God.
As scientist extraordinaire (most profoundly as inventor of the communications satellite) and author of an empire of science fiction books and films (most notably 2001: A Space Odyssey), Arthur C. Clarke is one of the most far-seeing visionaries of our time. Thus, his pithy quotations tug harder on our collective psyches for their inferred insights into humanity and our place in the cosmos. And none do so more than his famous three laws:
Clarke's First Law: "When a distinguished but elderly scientist states that something is possible he is almost certainly right. When he states that something is impossible, he is very probably wrong."
Clarke's Second Law: "The only way of discovering the limits of the possible is to venture a little way past them into the impossible."
Clarke's Third Law: "Any sufficiently advanced technology is indistinguishable from magic."
This last observation stimulated me to think more on the relationship of science and religion, particularly the impact the discovery of an Extra-Terrestrial Intelligence (ETI) would have on both traditions. To that end I would like to immodestly propose Shermer's Last Law (I don't believe in naming laws after oneself, so as the good book warns, the last shall be first and the first shall be last): "Any sufficiently advanced ETI is indistinguishable from God".
God is typically described by Western religions as omniscient and omnipotent. Since we are far from the mark on these traits, how could we possibly distinguish a God who has them absolutely, from an ETI who has them in relatively (to us) copious amounts? Thus, we would be unable to distinguish between absolute and relative omniscience and omnipotence. But if God were only relatively more knowing and powerful than us, then by definition it "would" be an ETI! Consider two observations and one deduction:
1. Biological evolution operates at a snail's pace compared to technological evolution (the former is Darwinian and requires generations of differential reproductive success, the latter is Lamarckian and can be implemented within a single generation). 2. The cosmos is very big and space is very empty ("Voyager I", our most distant spacecraft hurtling along at over 38,000 mph, will not reach the distance of even our sun's nearest neighbor, the Alpha Centauri system that it is "not" even headed toward, for over 75,000 years). Ergo, the probability of an ETI who is only slightly more advanced than us and also makes contact is virtually nil. If we ever do find ETI it will be as if a million-year-old "Homo erectus" were dropped into the middle of Manhattan, given a computer and cell phone and instructed to communicate with us. ETI would be to us as we would be to this early hominid — godlike.
Science and technology have changed our world more in the past century than it changed in the previous hundred centuries. It took 10,000 years to get from the cart to the airplane, but only 66 years to get from powered flight to a lunar landing. Moore's Law of computer power doubling every eighteen months continues unabated and is now down to about a year. Ray Kurzweil, in The Age of Spiritual Machines, calculates that there have been thirty-two doublings since World War II, and that the Singularity point may be upon us as early as 2030. The Singularity (as in the center of a black hole where matter is so dense that its gravity is infinite) is the point at which total computational power will rise to levels that are so far beyond anything that we can imagine that they will appear near infinite and thus, relatively speaking, be indistinguishable from omniscience (note the suffix!).
When this happens the world will change more in a decade than it did in the previous thousand decades. Extrapolate that out a hundred thousand years, or a million years (an eye blink on an evolutionary time scale and thus a realistic estimate of how far advanced ETI will be, unless we happen to be the first space-faring species, which is unlikely), and we get a gut-wrenching, mind-warping feel for just how godlike these creatures would seem.
In Clarke's 1953 novel Childhood's End, humanity reaches something like a Singularity (with help from ETIs) and must make the transition to a higher state of consciousness in order to grow out of childhood. One character early in the novel opines that "Science can destroy religion by ignoring it as well as by disproving its tenets. No one ever demonstrated, so far as I am aware, the nonexistence of Zeus or Thor, but they have few followers now."
Although science has not even remotely destroyed religion, Shermer's Last Law predicts that the relationship between the two will be profoundly effected by contact with ETI. To find out how we must follow Clarke's Second Law, venturing courageously past the limits of the possible and into the unknown. Ad astra!