Berry writes a monthly astronomy column in the Telegraph which is usually notable for its regurgitation of the traditional science facts that those mildly interested in the night sky are looking for. Where is Saturn? What meteor showers can be seen this month? That sort of thing. This month is different.
"Why we should dread finding life on Mars" is the headline. This precedes a little ramble about the more than 1000 exoplanets that have been found, and a note that none of them has been shown to have a trace of intelligent civilisations. In other words, the Fermi Paradox.
The Fermi Paradox arises from Enrico Fermi's question: "Where is everyone?" Where are all the alien civilisations? Why haven't we found them? Berry gives these possibilities:
Either aliens do not exist or they are extremely rare.I don't see the answer lying in either of those possibilities. There are other answers. Aliens exist but did not arise on planets where creation of the things we see as civilisation arose. Perhaps they were short of iron, or copper, or aluminium or silicon or some other limiting factor element that we take for granted.
Anyway, Berry goes on:
The latter possibility is the most frightening. If only a tiny number of civilisations exist then some unknown fate must have obliterated the rest. But if none exist, it is much more reassuring. It shows that we successfully evolved against seemingly impossible odds.Two things occur to me here. Firstly, the argument about seemingly impossible odds was the theme of Stephen Jay Gould's Wonderful Life, a recommended read. If the tape of human history were affected by nudges in evolution far back in time, we might not be here.
The second is that Berry is working with a sample size of N = 1 for his thinking. We have no idea if any civilisations exist anywhere else. It does not follow that "some unknown fate must have obliterated" any potential civilisations. It does not follow that some unknown fate will not obliterate ours. The paragraph is devoid of real content. Berry might be frightened. I don't think may others will be.
But one who seems to be concerned at least is the Swedish born philosopher Nick Bostrom. I hadn't heard of him or the Great Filter Hypothesis before today. I don't think I shall spent much time thinking about either of them. I don't have a lot of time for philosophers who seem to spend more time thinking about hypothetical futures than about realistic futures and although I might be doing Bostrom a disservice, that is what he seems to be earning his crust doing. Perhaps I should pay them some mind.
But I see the Great Filter Hypothesis as something akin to the Anthropic Principle. It actually adds nothing to our understanding - the idea that something unspecified prevents life turning into Galaxy wide explorers. My answer is "So what?" Based on a partial understanding of the N = 1 sample of species that have developed civilisation, I couldn't tell you what any other intelligent species that have developed civilisation might want to do. I just can't. I am not bothered about Klingons or Vogons or any other fictional species that might colour the thinking (or not) of philosophers of these things. I think there are plenty of reasons why we might not have found a civilisation beyond our own planet. I won't bother to list them. The wiki page on the Fermi Paradox covers them better than I could.
Bostrom has a strange notion:
I dread finding life on Mars. That would be bad news. Bit would be good news if we find Mars to be completely sterile. Dead rocks and lifeless sands would lift my spirits.Bully for him. If you want to read Bostrom in the original, so to speak, then click here and here. I find it odd that he can go from wanting there to be no life on Mars to there must be something that prevents our kind of human life spreading out across the galaxy. The leap of logic is so great that it doesn't exist. It is not a necessary conclusion. There clearly does not exist a Great Filter, and for Bostrom or Berry to have stated it so baldly they must have had good reason. In Berry's case, it is because he read Bostrom. In Bostrom's case, I don't know, because his argument doesn't seem to get past the problem of his leap of faith. Just because there aren't any other known civilisations doesn't mean they don't exist. And it does not mean our civilisation (or should I says civilisations) is doomed just because of a philosophical exercise.
One of Bostrom's ideas is that it is highly probable that we are living in a great computer simulation. Perhaps so. I wonder if he has the answer to the question "Does it matter if we were?"
I might come across here like one of those deniers that I rail against. I would suggest there is a difference. I am not talking about denying empirical evidence and well tested hypotheses. I am talking about disagreeing with the opinions of a philosopher. Having read what they have to say, I don't accept their conclusions. I am prepared to read more to see if they have uncovered an important truth. However, the whole idea of extraterrestrial intelligence is, in the end, an empirical one. The evidence will be the arbiter. N = 1 doesn't seem a good sample size on which to proceed.
As for Adrian Berry and his climate change denial. Try this page from his website. Not an edifying set of books for someone wanting to find the real truth about the universe.