Seth Shostak is the Senior Astronomer at the SETI Institute. We have seen that his description of SETI contains several points that converge with the approach that I take in The Design Matrix. Let me now make this even more clear with a posting by Steven Novella, who is a neurologist at Yale University School of Medicine.
Novella expands on Shostak’s explanation as follows:
What Seth is saying is that we have prior knowledge of the kinds of radio signals that nature is capable of producing. Natural radio signals have a signature – they are inefficient, which operationally means that they are spread out over a wide spectrum. So far, this has always been the case. There is no known natural process that produces a narrow band transmission. Therefore, SETI is searching for such a narrow-band signal.
But there is a flip side to this that Seth did not discuss – not only do we have knowledge of what kind of radio signals nature can produce, we have knowledge of what kind of radio signals can be generated deliberately by an intelligent race that has achieved radio astronomy (namely us). We can therefore say that a known marker or signature of technologically produced radio signals can be an efficient narrow band.
This is key – SETI is searching for signals that not only cannot currently be explained by nature, but have a positive feature known to be a marker of intelligent artifice.
I independently identified the same key – the coupling of the negative to the positive is essentially the very same argument I make in The Design Matrix:
The key is that an analogy to designed things is coupled to a discontinuity with non-teleological processes. They are two sides of the same coin.
The examples of the Face on Mars, a message in the DNA, Darwin’s brass men, and the PCP degradation pathway all converge to highlight the power of a demonstrated analogy with designed things coupled to a demonstrated discontinuity when concluding design. Join the two and there is a strong design inference. Fail to join the two and there are serious problems trying to infer design. Let us now deepen and extend this insight as we prepare a methodology that will help us traverse the Explanatory Continuum in an effort to better assess our suspicions of design.
Novella then continues:
Presumably, however, if SETI did find a candidate signal that had the markers of artifice and lacked a natural explanation, we would then take a closer look at the signal and look for encoded information.
If we found it, how would we know if the information is the product of natural processes or deliberate intelligent artifice?
Well – we would go through the same process. Is there anything known in nature that can account for the information, and if not does the information contain any positive evidence or marker for artifice? One such marker of technological intelligence is mathematics. This is what leads to Carl Sagan’s idea that something like a series of prime numbers would be a possible intelligent tag in an ET signal.
This again is much like The Matrix, where I advocate that we don’t sit back and proclaim “design” upon finding some clue to support a design inference, but instead look more closely – a higher resolution analysis. This is, after all, the whole point of the scoring things in the context of the Explanatory Continuum (from my above quote). It’s the whole point behind using the Face as a metaphor.
This is an important point because I was under the impression that Shostak would conclude the existence of ETI because of the discovery of “a persistent, narrow-band whistle.” Yet in reality, most scientists would likely consider this discovery as mere evidence that suggests ETI exists and would want something more solid, thus calling for a closer look. In other words, we now exist at a stage where the existence of ETI is possible or weakly plausible. The discovery of a persistent, narrow-band whistle would make the existence of ETI solidly plausible, perhaps weakly probable. But something more would be needed to make it highly probable.
So how do we get there? Novella suggests we simply repeat the process of coupling discontinuity and analogy at a higher resolution, where “Carl Sagan’s idea that something like a series of prime numbers would be a possible intelligent tag” vastly enhances the strength of the analogy.
Novella also notes that the positive markers are limited to analogies with the only known intelligent agents – us:
We are using, here, ourselves as the only known (to us) model of technological intelligence.
SETI, therefore, combines two criteria in its search for intelligence. The first is negative – finding an anomaly that cannot be explained by known natural processes. The second, however, is positive – finding that the signal has markers of technological intelligence, as best as we can infer from our solitary self-example.
Again, this is essentially the same approach I take:
To more effectively infer design, in an empirical, investigative sense, we will restrain our hypothesis to invoking a human-like intelligence. If the intelligent cause is completely unlike human intelligence, how would an investigation recognize the signposts of its intervention? If the intelligence is completely unlike us, it would not think or design as we do. As long as the hypothesized agency is human-like, we can more safely extrapolate from our own experience with our own intelligence and design. And such extrapolations make it possible to formulate testable hypotheses.
Thus, we can see that the core approach that SETI uses to detect an artifact is essentially the same process that I advocate in The Design Matrix. There are some differences at the edges, as I shall explain later, but that I independently converged on the same investigative logic/approach allows this author to enjoy a subjective sense of validation. 🙂
Let me conclude with the following comment from Novella:
Also – we can take Seth’s statement of the difference between complex and artificial and apply it to biology (as Seth briefly does himself in his article). From what we know so far it seems that inefficiency is a general marker of natural systems, and “narrow band” type efficiency is a marker of deliberate artifice. The information in DNA is not efficient. It’s a mess. It’s exactly what we would expect from a naturally self-organizing system. It does not reflect the elegant simplicity or efficiency of artifice.
I am not proposing this line of evidence as strong evidence for evolution by itself. But for what it’s worth – this one goes in the evolution column, not the ID column.
I would agree with Novella’s assessment and I also like how he formulates it. By putting arguments/facts in “columns,” he has come close to scoring things as I advocate (he’s actually drawing on the Criterion of Rationality). But any honest investigation should be open-ended, such that the same argument could be used to place things in the “ID column.” As such, I would simply note that the Genetic Code (which is different from DNA) is clearly not “a mess.” On the contrary, the Code is exceptionally well designed according to several different parameters. If one can make this case (and I can), an intellectually honest approach would admit we have a positive marker for life’s design – something to put in the design column.