Let’s consider the methodology that SETI employs to detect the existence of design.
First, SETI builds on two scientific facts: 1)The universe contains an immense number of stars and 2) Intelligent life, capable of producing technology, evolved on this planet.
This foundation is then used to ask a question: Since intelligent life exists on this planet, and the universe contains many stars, many of which could have their own planets, might not intelligent life exist on other planets?
The scientific answer at this point is, “Maybe, maybe not.” In other words, “Who knows?” Of course, if one is going to go to all the trouble and search for alien intelligence, one probably has some reason to believe ETI does exist. This reason is supposed to come from the Drake equation. But as Michael Crichton pointed out, the variables of the Drake equation are subjectively determined. Thus, the Drake equation does not tell us anything about the objective world around us. In fact, this excerpt from SETI’s senior astronomer, Seth Shostak, should clue you that the Drake equation is just window dressing:
Why do we think that E.T. is out there in the first place? It’s simply a matter of numbers….it’s likely that the number of planets is an order of magnitude larger, or 10^23, which is the number of grains of sand on all the beaches of Earth. That’s a lot of real estate, so if you think that Earth is the only grain of sand where anything interesting is happening, one has to admire your audacity.
In other words, there are so many planets out there that it would be audacious (!) to think we are the only intelligent beings that exist. That’s the whole argument. Appealing, yes, but also quite subjective.
While the question at the heart of SETI is rooted in scientific fact, the search itself is not science in action. This explains why so very few actual scientists even bother with SETI. However, unless one is a proponent of scientism, this fact alone does not invalidate the search. After all, science is not required to make discoveries about the world.
So how does SETI actually set out to search for ETI?
First, SETI is making an assumption that there is nothing terribly unique or special about human intelligence. Not only would it feel audacious to think so, but we require this assumption to proceed with the search. This is because SETI uses human intelligence and behavior as a proxy for the sought after alien intelligence. For example, since we have developed radio technology and are obsessed with communication, it is assumed these human traits also exist in aliens. If they didn’t, SETI could not even get off the ground.
This working is assumption is rooted in Analogy. So it is the Argument from Analogy that provides the guidance for the investigation. Yet the assumption and analogy deepens, in that not only does SETI assume there are other human-like intelligences that communicate with radio technology, but that there are some that are looking for other intelligences by trying to get their attention.
So far, we can see that the search is rooted in a subjective intuition that uses an assumption, rooted in Analogy, to anticipate the existence of a specified pattern – a persistent, narrow-band whistle. What’s more, the criterion of Analogy is coupled to the criterion of Discontinuity, as this persistent, narrow-band whistle would also represent something that could not be explained by our current understanding of natural processes.
While SETI’s 40-year search has a track record of complete failure (not being science, its subjective working assumption is unfalsifiable, after all), what if this whistle is found? Given the coupling of Analogy and Discontinuity, I would consider it evidence for ETI. However, it would simply be cause to tentatively propose the existence of ETI, cause to suspect its existence as plausible. In essence, the narrow-band whistle would be similar to the vague Face on Mars from the 1970s. A higher resolution analysis would be needed. We need a detailed Face on Mars.
As explained in the last posting, this higher resolution analysis would entail the search for some message or pattern in the region of the whistle. The message itself would simply be an attempt to deepen the criterion of Analogy and Discontinuity. That is, while a persistent, narrow-band whistle would be both analogous to intelligent causation and not well explained by natural processes, a fortiori, a message would be even more analogous to intelligent causation and arguments for natural causation would become unreasonable. In other words, SETI would have detected the design of another mind without having a single shred of independent information about the designers. Instead, working assumptions about the designers were provided by Analogy (using humans as a proxy) that was boosted by coupling it to Discontinuity.
In summary, I, along with many other skeptics, do not think SETI is science, largely because of its inherently subjective rationale. However, since we can and do make discoveries without science, this is not really an argument against SETI. SETI’s rationale, while subjective, is not whimsical or unreasonable. And if they succeed in detecting design in the skies, they will have proven what is already known by yours truly – you don’t need independent information about the designers to infer design.