I thoroughly enjoyed reading the interviews of Dembski, Gonzalez, and Behe in the recent article here. I wanted to talk about something Gonzalez said in the interview. Specifically the transformation from ETI (Extra Terrestrial Intelligence) optimist to ETI pessimist. I’ve undergone a similar transformation for the same reasons. Indeed, when I received my monthly Scientific American in 2001 with Gonzalez’ “The Galactic Habitable Zone” featured on the cover I was delighted to see that someone was seriously working on filling in the blanks in Drake’s Equation and that the work was important enough to make the cover of my favorite and primary source of what was happening in the world of science.
As an avid reader of what’s called “hard” science fiction (science fiction which incorporates as much as possible from actual experimental sciences into the plot) for the last 40 years and counting I recognized Gonzalez work as having important implications for hard science fiction. SETI, The Drake Equation, and The Fermi Paradox have played prominent roles in formulating hard sci-fi plots for as many years as I’ve been reading them. SETI, for anyone that doesn’t know, is the “Search for Extra Terrestrial Intelligence” and began in earnest in 1960, just a few years before I was able to read and understand the contents of encyclopedias. I had a subscription to the World Book Encyclopedia science supplements in the early 1960s. Astronomy and cosmology have always been good subjects for popular science because of the breathtakingly beautiful pictures that go along with it and the sheer magnitude of what’s being explored. While my peers were reading Tom Sawyer and Huckleberry Finn in grammar school, those of my peers that bothered to read anything at all, I was reading hard science. What I’m saying is SETI and I were born together and grew up together.
After nearly 50 years of earnest search SETI has uncovered exactly nothing in the way of ETI. A grand disappointment for many including me and evidently Gonzalez too but one must go where the evidence leads even when it leads to a place we wished it didn’t. The Drake Equation was formulated in 1960 and is:
N = rs * fp * ne * fl * fi * fc * lt
where:
N is the number of civilizations in our galaxy with which we might hope to be able to communicate;
and
rs is the average rate of star formation in our galaxy
fp is the fraction of those stars that have planets
ne is the average number of planets that can potentially support life per star that has planets
fl is the fraction of the above that actually go on to develop life at some point
fi is the fraction of the above that actually go on to develop intelligent life
fc is the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
lt is the length of time such civilizations release detectable signals into space.
Very little was known about the actual values of any of the variables in 1960 but what seemed to be reasonable estimations invariably yielded a large number of civilizations and this is what has kept SETI alive all these years.
The Fermi Paradox is “Why haven’t we heard from them?”. In 1950 physicist Enrico Fermi, in a lunch with colleagues, posed the question “If there are many advanced civilizations in the galaxy why haven’t we seen or heard from them?”. Back then the principle used to support the idea that there must be many ETIs is the same principle that launched the enlightenment “The Copernican Principle of Mediocrity” which states that the earth is not a special creation but rather an average planet orbiting an average star in an average location in an average galaxy and by extension nothing on the earth is out of the ordinary including intelligent life. Not surprisingly this principle, which is some 500 years old and has been a highly successful heuristic beginning with its explanation of heliocentricity, is not easily abandoned. It hasn’t been easily abandoned by me either but when the evidence becomes overwhelming then dearly held principles must be let go if one is to adhere to the nature of scientific enterprise – go where the evidence leads.
The evidence has led to an undeniably rare earth. Gonzalez didn’t expect the evidence to lead there any more than I but we both accepted it and changed our beliefs accordingly. Unlike me, Gonzalez actually pioneered some very important experimental work that helped fill in the variables in the Drake Equation and thus explain the Fermi Paradox. It looks like we’re alone. I wouldn’t have believed it had the evidence not been so convincing. Thank you, Guillermo Gonzalez. You are a shining example of scientific acheivement and integrity. What is actually true must always trump what we fervently wish to be true. It’s an unpardonable sin expelling this man from the halls of scientific inquiry. There is no doubt in mind that if he submitted the same article (“The Galactic Habitable Zone”) to Scientific American today it would be roundly rejected instead of being made the cover story. All because he associated himnself with a politically incorrect (in the politics of science) movement – Intelligent Design. What a travesty of justice and gross miscarriage of scientific integrity. It is my fervent wish those responsible are held to account for it.