As a scientist I am interested in the scientific pursuit of answers to matters of nature. One which has long been on my list is the age old wonder about is there intelligent life elsewhere in the universe. The technology is improving quickly to help us get a handle on what may the chances of encountering life on other planets, especially in other solar systems.

            One project which is now fifty years old is SETI (Search for Extra Terrestrial Intelligence) headed by Dr. Frank Drake. He devised the so-called “Greenbank Formula” (so named for the Greenbank Laboratories which is involved in this research). It is an attempt to grasp the averages and probabilities of there being intelligent civilizations out in the cosmos. Its concept is simple and based on multiplying several factors – some known and most unknown quantities – starting with how frequently new stars are born in our galaxy. Our best research indicates that this number is about twenty per year. The next is how many other stars actually have planetary companions. Until very recently this was an unknown quantity but research over the last two decades has found approximately 200 planets encircling other stars and they are being found in ever increasing frequency. From there on in the factors are unknowns. The next question is how many stars have Earthlike planets. It goes from there to planets which have spawned life forms, then on to how many planets have higher life forms, then those which have developed technical civilizations, and then those which have become technologically advanced but avoided destroying itself.

            As we all know if you have a formula such as this one which has several factors, of which only two are known quantities, the formula can not be concluded with any degree of certainty. But being human beings, scientists can not resist speculating and try to calculate the formula to its successful end by interposing “educated guesses” in the unknown quantities. Of course, a wide variety of answers result ranging from the wildly pessimistic to the wildly optimistic, all of which are no more valid than the other, but it is nonetheless fun to play with. But as Dr. Drake likes to say, “The average of each of these comes out to be about 10,000 technologically advanced civilizations within our galaxy.”

            For the average person the fact that the people who are making such proposals are “scientists” means that they must be true. But for those of us who know anything about statistics or the laws of probability, we realize that such a degree of speculation with so little information to draw an accurate conclusion on is nothing short of rubbish.

            To illustrate this point allow me to make this comparison; There are two men on death row and the governor announces that he has decided to commute one of their sentences to life imprisonment, but he hasn’t yet decided which one will go to the electric chair. Both men are notified of this news and they begin to think that this announcement ahs just doubled their chances. Or has it really? Consider this: For the one whose sentence will be commuted to life, his chances were 100% but for the one who will be electrocuted his chances remain unchanged. So in fact, no one’s chances for survival were improved by 50%.

            As this anecdote demonstrates, the probability on improves any proposition if all the factors are known quantities and if only part of the factors are known quantities, nothing has changed and any attempt to calculate the odds is an exercise in futility and as such is nothing more than someone trying to convince themselves of something they want to believe even if the people playing the game are world renowned scientists.

            At this point I must now also add that in recent times other exobiologists have asserted that the Greenbank Formula neglects and disregards factors which we now know to be requirements for the formula to be useful and accurate. One is that the presence within the solar system of a large Jupiter type planet acts as an asteroid deflector as its powerful gravity draws them away from inner terrestrial planets otherwise the Earth would have been absolutely pummeled by asteroid impacts throughout planetary history and thus prevent much in the way of higher life forms from taking hold due to being constantly being interrupted by cataclysms.

Next there needs to be an abundance of cometary bodies in the planetary neighborhood which would supply the water as well as the organic and amino acids which the ones we have researched apparently do, which would be the required additions to the chemistry needed to get things moving.

So, albeit loads of fun to speculate and calculate the averages of anything or attempt to project future environmental or cosmic trends, unless you can identify all the factors to create a formula and then you further know the accurate answers to each of the factors, any and all attempts to reach anything resembling an accurate answer is nothing more than a childish game of knowing what answer you want and finding a “good sounding” collection of factors which will lead to an equally good sounding conclusion is in full reality just another form of self delusion, even if it is a group of highly regarded scientists playing the game. They are after all, just people too.