SETI: To the Unknown, Full Speed Ahead
This year marks the 50th year of the search for extraterrestrial intelligence (SETI). Seth Shostak, senior astronomer at the SETI Institute and one of its most outspoken spokesmen, made the cover of Sky and Telescope’s November 2010 issue. He stands proudly over his Allen Telescope Array in his feature story, “Closing in on E.T.” celebrating “SETI: 50 Years and Beyond.” He also got space on the Sky & Telescope website to discuss “The Future of SETI.” They’re mostly technology articles, discussing the old and new ways of looking for signals as hardware and software improves. Did he say anything to scientifically justify the search? Not much.
“Despite a half-century of SETI experiments,” he began in the print article, “we still don’t know if there’s anyone out there as clever as we are.” The web article began, “As far as we know, we’re alone in the universe.” No sense looking close by, he continued: “But nearby life, if it exists at all, is undoubtedly dumb. If we want to look for smarter extraterrestrial biology – the kind that could rival or perhaps far surpass us humans for reasoning, inventing, and building – we have to look much farther afield, among the stars. And we don’t know where.”
What keeps him going is the fact that even the best current searches are sampling only a paltry amount of space in one galaxy – our Milky Way – out of billions. Shostak’s articles provide an entertaining way to learn all about radio waves, optics, antennas, statistical search strategies and interferometry. He assumes that every reader wants to find aliens – indeed, many in the public find it fascinating and think it worthwhile. But what is really important about this search program are the philosophical and possibly theological implications for a successful detection of alien intelligence. About this, he said nothing. Neither did Paul Shuch of the SETI League, a group of radio amateur SETI enthusiasts, who added another article in the November issue about their ham radio approach to detection. “So far the SETI League’s search has been exactly as successful as every other SETI project!” he beamed whimsically, aware that they are “hearing nothing.” The fun is in just trying.
“There’s no denying that SETI is an uncertain enterprise,” Shostak said, hedging his bets a little. “No one can tell when or if success will ever come.” He placed his SETI crew in the tradition of great explorers, “akin to that of Christopher Columbus as he sailed past the breakwaters of Palos de la Frontera in August 1492 and headed into the rolling swells of the Atlantic” – i.e, at just the start of the trip. “It’s still very early days, and the great excitement lies before us.”
Columbus, however, had high confidence in success at landing somewhere. Columbus knew that China was out there, and it had Chinese intelligences willing to trade their goods. Shostak and most SETI enthusiasts base their entire hopes on a sample of one – human beings – whom they assume evolved from particles.
The same positivist confidence was palpable in a NASA Astrobiology symposium this week, featuring panelists and scientists working on various aspects of the origin of life. It seemed only a matter of time before we find life of some kind, intelligent or not. One questioner in the audience, however, offered up a question that only got blank stares: what if life is not found? The panelists had apparently not given much thought to the possibility of failure.
David Grinspoon, who was on the webcast, also wrote about this in the November Sky & Telescope in the context of discussing a strange ballot initiative in Denver seeking to set up an “Extraterrestrial Affairs Commission” (see campaign website, something Grinspoon, an ardent astrobiologist, opposes because of its alien conspiracy leanings. But he had this to say about the possibility of not finding life out there:
I do believe in aliens – as much as I can, being a scientist – believe in anything without actual evidence. A universe teeming with life is consistent with what we have learned about the history of the Earth, the apparent requirements for life, and the materials and environments that exist elsewhere in the universe. Given all this, to propose that life, and even intelligent life, is unique to Earth seems the scientifically less plausible condition.
Yet anything can seem plausible in the absence of evidence. His wording did not rule out an intelligent cause for extraterrestrial life, but later he did say, “To think deeply about the possibility of alien intelligence we need to ponder our origin, evolution, and uniqueness.” He ended by encouraging “critical thinking and teaching people how to evaluate evidence and avoid being taken in by bogus claims.” Apparently he was thinking of extraterrestrial conspiracies – not his own belief in aliens.
The editor of Sky & Telescope, Robert Naeye, was less hopeful in his opening editorial to the SETI issue. He even considered humans as potentially unique: “Given the lack of reproducible evidence for E.T., and that humans have a highly anomalous combination of abilities that makes us unique in our planet’s history, I wouldn’t be surprised if the closest technological civilization lives in another galaxy,” he said. We need to “keep our minds wide open,” he continued, jesting, “but not so open that our brains fall out.” His pessimism was a foil for the confidence of Shostak and Shuch. “The history of astronomical discovery suggests that if we ever detect another civilization, it will probably be serendipitous. Unfortunately, I don’t expect this to happen in my lifetime.”
Secularists and the religious know so little about what is out there, it is foolhardy to be dogmatic. There is no basis for making rational estimates from either an evolutionary or a theistic position. Consider the extremes: to an evolutionist, life could be common or unique. To a theist, life could be common or unique. The evolutionist would be more surprised if life is unique, and some theists might be surprised if life is common, but no firm prediction can be made either way. No matter the result, both camps will doubtless find a way to incorporate it into their world view.
So isn’t it better to do something and search? Won’t this alleviate our ignorance? The diagrams in Shostak’s article are not encouraging. Even with the Allen Telescope Array’s expanded reach, the search space is a relatively small sphere in one spiral arm of the Milky Way. It has taken years and millions of dollars to search that far. Would people still be giving money in 2079 if nothing has been detected by then? What are the criteria for failure? The public cannot be led along the primrose path forever. Undoubtedly some spin-off benefits will come in radio and optical technology and in software design, but those could be found through traditional science. But you can’t have a science without evidence. Shostak is doing a great job demonstrating the sophistication of his ignorance.
The history of science can provide illuminating examples. The classic case is alchemy. This “science” was highly respected for centuries. Even the great Isaac Newton dabbled in it with some passion. Alchemists used the tools of chemistry to search for a hidden reality that existed only in their mind’s eye: the possibility of turning base metals into gold. They had much of the same intense confidence in their quest seen in today’s SETI folk. They felt they were getting warmer, and warmer, and their tools and techniques better and better. It was only a matter of time. And they knew gold existed! SETI doesn’t even know that much. They know humans exist, but humans are not aliens in the way they think of them evolving independently. Alchemy finally had to be abandoned, as real chemistry began to supplant it. It was eventually deemed a pseudoscience. It had never been a science in the first place.
What if SETI succeeds? Will it then become a science? Will the years leading up to detection count as scientific work? Perhaps. But what if it fails? Like alchemy, will it be abandoned or replaced with a new science acknowledging human uniqueness? Nobody knows. All we can say for now is that, like alchemy, it is not a science merely for using the tools of science, because no evidence exists for life beyond the earth, let alone intelligent life (08/12/2010). SETI could be a fool’s errand. With no criteria for failure, with no end-point in sight, it will look more and more foolish as time goes on, while its proponents can always claim they are getting warmer. It’s been 50 years so far. How much time do they get? A century? A millennium? Eventually watchers will complain that SETI has become a perpetual job-security gimmick.
By assuming that detectable physical signals carrying a message with purposeful intent might exist, and by employing their intelligence to make contact with it, SETI researchers are accomplishing something many of them would resent hearing: they are validating the legitimacy of intelligent design science (12/03/2005), and they are recognizing their own uniqueness as rational, mindful creatures capable of acting with purpose and intent. This is something that an unguided process like natural selection is incapable of generating. Intelligence must be viewed as existing in the conceptual realm, not the physical realm. The conceptual realm presupposes immutability and integrity. For greatest likelihood of success, therefore, the search for extraterrestrial intelligence should begin looking in places where the purpose that brought sentience into the physical realm has been revealed.