The spaceship comes down in your backyard, crushing a bed of petunias, and out steps the alien. This is always an awkward social moment. What, exactly, do you say to someone who may hold the secrets to the universe? After, that is, you finish quivering and quaking and wondering if he (she? it?) is going to suck you down like a raw oyster?
Obviously you would want to get some information out of the alien--no easy trick, to judge from most alien-encounter narratives. The aliens who show up in the middle of the night and abduct people are notoriously stingy with information. They never solve any mathematical equations. They don't offer up the long-sought simple and "elegant" proof of Fermat's Last Theorem. They don't tell us where Jimmy Hoffa is buried.
When aliens do communicate with humans, they're always a bit like the Michael Rennie alien in the 1951 movie The Day the Earth Stood Still: They tell us to behave. They say we need to get our act together. They're self-help gurus. A fellow named Darryl Anka channeled an alien named Bashar for many years, and Bashar, though wise, didn't really have much data to offer, just advice on how to live a better life. (Anka, when I last spoke to him, said he'd given up channeling Bashar and was working on designing a UFO theme park.)
There's a scene in Carl Sagan's excellent novel Contact when Ellie Arroway, his protagonist, whooshes down some kind of intragalactic "wormhole" and winds up on a sunny beach, face to face with an alien. The alien, annoyingly, doesn't seem to know who built that wormhole subway system. Eventually Arroway gets around to asking what is no doubt her most urgent question: "I want to know what you think of us, what you really think."
Wow. That's really the wrong question there. That's blowing it big time. This gal crosses half the galaxy and is tossed and rattled around to within an inch of her life, and when it's over she starts fishing for a compliment!
No, a better question to an alien would be: What are you made of? Are you based on carbon and liquid water? Do you have DNA as your information-bearing molecule or something like it?
Stephen Jay Gould put it this way, on Timothy Ferris' recent PBS program Life Beyond Earth: "What's your biochemistry?"
Some people may argue that other questions should precede the biological ones. They might, for example, choose a political question, asking who, exactly, is in charge of this universe. Or they may skew theological, and ask if there's a God and what exactly he's got on his mind.
A good argument could be made that a physicist should pose the first batch of questions to an alien, asking whether it's possible to go faster than the speed of light and whether there are other universes outside our own. The physicist and the alien would no doubt get embroiled in a discussion of string theory, and soon they'd be jotting down incomprehensible equations about 10-dimensional vibrating loops. Maybe at the end of the encounter we'd figure out how to yank free energy out of the quantum vacuum. We'd have a new trick for cooking a hot dog.
My feeling is that the biology questions trump everything else. We know essentially nothing about life beyond Earth. Because we are ignorant of other biological systems, we have no context for understanding Earth life, for knowing to what extent the life we see around us is, on the cosmic scale, relatively ordinary or totally freakish.
We don't know, for example, if Earthlike planets are common. We look around our own solar system, and what appears to be common are planets that have no life whatsoever. We also see signs that Venus and Mars were once more hospitable to life and over many hundreds of millions of years became inhospitable. Bad stuff happens to good planets. It'd be nice to know more about that trend.
We also don't know how life originates and to what extent it evolves in an orderly pattern. The debate in Kansas over the teaching of evolution misses the real debates within the field. There are those who argue passionately that life originated with a single replicated molecule. Another camp favors the notion that it began with a kind of garbage bag of molecules that more or less eased its way from nonlife to life. And the biggest question may be to what extent evolution is divergent or convergent. Divergence gives us a bewildering variety of life; convergence gives rise, repeatedly, to certain anatomical features, like wings and eyeballs. You can make an argument that intelligence is an extremely unlikely, random, quirky event in terrestrial biology, or you can make the counter-argument that you can see intelligence coming down the pike from many millions of years in advance. On that issue hinges the abundance of intelligent life in the universe.
How likely is it that life elsewhere will go through the same evolutionary leaps as life on Earth? To take one obscure but critical example: Life on Earth remained entirely one-celled for 3 billion years. For at least half of that time, those cells didn't have a nucleus. They couldn't use oxygen in their metabolism. They were pitiful even by microbial standards. So, how lucky was the evolutionary leap from prokaryotes (non-nucleated microbes) to eukaryotes (nucleated, and using oxygen)? It happened here about 2.1 billion years ago. Was that our lucky break? Or does life, in general, figure out the trick of using oxygen and growing big and brawny?
And, of course, we don't really know what we're talking about when we talk about "intelligence." We tend to think of creatures that use technology and language. But that could be shortsighted. Maybe most intelligent creatures are dolphinoids, blissfully swimming in an alien ocean with little interest in building spaceships.
Imagine for a moment that we could see the universe through the eyes of an alien creature. Would the universe look more or less the same? Or would we be confused, dazzled, and feel as though we were hallucinating?
Are the aliens interested in the same things that interest us? Could we carry on a meaningful conversation?
We should prepare ourselves for finding something out there that's totally unexpected. And we have to prepare for bad news, or at least bad news in the context of our Star Trek fantasy. We may have wildly overestimated the abundance of extraterrestrial civilizations. Carl Sagan thought there were millions such civilizations in existence right now in our own galaxy. The actual number may be a handful. Or we could be, as Sagan's old collaborator I.S. Shklovskii argued, "functionally alone." Not literally alone, just so isolated that there's no practical way to make contact of any kind with another intelligent species.
Whatever we do, we shouldn't take ourselves for granted. There may be something extremely rare and wonderful about a world in which water splashes on the surface, and where life survives for nearly 4 billion years, where it has the leisure to evolve and, through natural selection, explore the possibilities of complexity.
The search for life beyond Earth always doubles back to our own existence. Why are we this way? How did we come about? How special is it to be a thinking organism? This is the kind of stuff you'd want to discuss with the aliens. And remember, they like it when you compliment them on the really cool spaceship.