January 18, 2009

Guest Blogger: Russell Blackford: Where's my alien civilisation? Part 2.

Where were we?

This year we have Darwin's 200th birthday and the 150th anniversary of the publication of On the Origin of Species. It's a natural time for thoughts to turn to issues about the origins of life and the trajectory of biological evolution. It was in that context that I found myself, this week, thinking again about the Fermi paradox and the mysteries of the Drake equation, after some discussion of these over on Richard Dawkins' site. The discussion on Dawkins' site got a bit acrimonious, for some reason, but I'm sure we can avoid that here.

At the end of Part 1., I left the Fermi paradox with questions about the fate of technological civilisations. Do they self-destruct? Do they become unrecognisable to us? Or does the rate of technological progress flatten out, in which case we are not approaching a technological singularity – rather, we are somewhere on the steep part of a sigmoid curve.

Deeper into Drake's equation

I suspect that the evidence that we're on a sigmoid curve is pretty much illusory. E.g., the evidence from science fiction is probably just evidence of limits to our imaginative capacities. Still, it's not a scenario that can be ruled out (and it seems just as possible to me as the technological singularity scenario). It's certainly conceivable that at least some kinds of technological progress flatten out. At 1 per cent of the speed of light it would take us over 400 years to reach the nearest stars. We don't know how much longer to reach the nearest worlds that could easily be colonised. We tend to think that the problems will be solved in millions of years of future progress, but we may not be good at working out what problems can and cannot be solved, at least easily enough to be worth the effort, even over very long tracts of time.

That said, I'd prefer to look for an explanation deeper in the Drake equation, which uses several variables to calculate the number of technologically advanced species in our galaxy. The variables include the average rate of star formation, the fraction of stars that have planets, the fraction of planets that can potentially support life, the fraction of these that actually develop life, the fraction of these where intelligent life evolves, the fraction of these that develop civilisations that send detectable signs of themselves into space, and the length of time that such civilisations exist.

Some of the fractions that feed into the Drake equation may be very small indeed, so small as to make technologically advanced species, and the civilisations they create, incredibly rare. It's consistent with what we now know that the conditions required for life to form are extremely fortuitous and unusual. It may need very rare combinations of environmental factors. And even then, you can have life staying at levels of neurological complexity that don't lead to technology.

We know that life can stay at levels of intelligence well below our own pretty much indefinitely. If not for one or more catastrophic events at the end of the Cretaceous Period, including the bolide impact that caused the Chicxulub Crater, Earth might still be dominated by dinosaurs, which might not have developed any impressive levels of intelligence. They hadn't done so in the previous 150-odd million years, so there's no reason to think they would have in the past 65 million years.

We really need to know a lot more, and we soon reach a point where people are relying on nothing more than hunches. With that disclaimer, my hunch is that the evolution of a technological civilisation to our sort of level or beyond is a statistically improbable event. I.e., it is an event that takes place quite infrequently in an average galaxy. I can't be much more precise about what "quite infrequently" means, except to say that I wouldn't be at all surprised if human beings were the only species in our galaxy to have created technological civilisations.

There's a lot of things we'd need to know before we could say anything more confidently, or more precise, than that. E.g., we'd need a well-corroborated theory of the origin of life to give us an idea of how rare the conditions for it really are. We just don't have one. We have a well-corroborated theory of how life diversifies - neo-Darwinian evolutionary biology - but not of how it gets started. The best we have is an idea of what sort of theory would be a workable account of abiogenesis – some kind of theory of early kinds of self-replicating molecules that were able to develop into the building blocks for the kinds of life forms from which we, and the rest of contemporary life on Earth, all eventually diversified.

There are so many unknowns about all this that I think we're a long way from being able to deduce any pessimistic conclusions about humanity's future. Even if life itself is more common in the universe than appears so far, the evolution of human-level intelligence might be very rare indeed. Even if technological change ends up following a sigmoid curve, we don't know how to unpack the detail of that – it might mean that space travel at appreciable fractions of the speed of light is going to turn out more difficult than we commonly assume … but, for all that, our ability to transform our capacities may reach levels far beyond what is current. We can't predict the future, though we can forecast and consider various possibilities and scenarios.

Still waiting

Meanwhile, I'm still waiting for my alien civilisation. I'm also waiting for my jet car. If it doesn't turn up before I shuffle off this mortal coil, I don't know if that's a reason for pessimism or optimism.

Where has the damn thing gone?


Russell Blackford is an Australian philosopher. He has published extensively (novels, short stories, academic monographs and articles, and book reviews) and is editor-in-chief of The Journal of Evolution and Technology. His home blog is Metamagician and the Hellfire Club.

4 comments:

The Missed Call Of Cthulhu said...

There’s something I’d personally like to see discussed more in regards to the Fermi paradox and that’s anthropology. I think it’s a discipline under represented in these discussions. I have no special expertise in it myself, but it seems to me worth noting that we can 1) develop a crude idea about what percentage of cultures developed by an intelligent species become technological civilizations by examine our own civilizations here on Earth, and 2) look to see what combinations of political, social, environmental forces promote that kind of development, and 3) see what combination of cultures accelerate technological development the most, or, conversely, retard technological development almost entirely.

We can only assume that any planet with enough geographic diversity, of significant scale to its inhabitants and with a significant population would develop a myriad of cultures, on Earth we see our own cultural diversity disappearing- small cultures being (largely) absorbed by larger cultures. Does this trend suggest that eventually we will have one culture which dominates the planet? Would one monolithic culture retard our technological progress? (My thinking is yes.) Would a death struggle between two cultures increase the likeliness of our self destruction? (My thinking is yes.)

And then more broadly, who are the anthropologists that we should bring into the discussion? And what other disciplines (beyond the ones already discussing it) could help us flesh out some of these other variables?

Paul Hughes said...

Russell,

Because we are on the downside of the intelligence bootstrapped singularity, our lack of seeing alien civilizations could be explained by our Low IQ, anthropological chauvinism. I wrote about this in my essay "Exotic Civilizations: A Possible Answer to Fermi's Paradox' here:

http://blissful.co.nz/library/exotic-civilizations-beyond-ka.php

Brian said...

Hi Russell. In my ignorant opinion, intelligent life that hangs about for a long time, long enough to get some high speed space travel, is improbable, at least up to this point in time. If you need 2nd or 3rd generation stars to provide the raw material for an Earth-like planet and then you need to avoid catastrophes like you mentioned then has there been so many billions of years in which this would happen regularly. Having said that, there are an awful lot of Galaxies out there that probably improve the odds a lot...

Michael Kirkland said...

We do in fact have flying cars. Yes, they're expensive, but that's mostly an issue of scale.

We certainly have the technology for a flying car in every driveway. That's not what's stopping it.

You just can't be trusted not to crash them.