This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
These are two posts from the Life, Unbounded archives. They were written in April and May 2010. Around that time there was a lot of media noise about aliens - brought on in part by Stephen Hawking's comments about fearsome "nomadic" lifeforms that might roam the universe. I've merged the posts here. As far as I know the idea about "meme armor" is an original one.
Debate about "intelligent" life in the universe is tricky. It's long been colored by wild extrapolation, optimism, pessimism, and downright fantasy. But there is a need to think about it responsibly, because the question is real enough. The SETI program and SETI Institute have held out against many challenges to do just this. While I prefer an approach based directly on the blossoming science of exoplanets, it's still fun to take the occasional dip into more speculative terrain.
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It was amusing to see discussion in the media based on some comments by Stephen Hawking (all good promotional material for his most recent TV offering). He raises the notion that it may be very, very bad for us if we ever come into contact with intelligent aliens. This is of course not exactly a new idea, but it can take on a number of forms - some more interesting than others. The Hollywood version is that advanced aliens might just be mean, hungry, and well armed. The version that I think is worth a bit more thought is to do with the slightly (only slightly) more realistic case where, rather than descending on us with hefty weapon-bristling spaceships, the aliens are simply communicating with us from afar.
Ideas, it has been said, are dangerous things. A distant, intelligent, alien race could tell us stuff that might shock us, confuse us, and possibly destroy us - all without ever leaving their home planet. They might actually be trying to be friendly, but inadvertently light a cultural, philosophical, and scientific fire that sends humanity up in smoke. It could be like showing a medieval baron how to make a nuclear weapon, or something more subtle and insidious. Richard Dawkins coined the term 'meme' for a unit of cultural ideas or practices - and it's appropriate here - memes can propagate, much like a virus. An alien meme ('the universe is going to end in one year, and we have proof') could tap into our most lemming-like instincts and make it very hard for us to function as a species.
Presumably a sufficiently advanced alien species would understand the potential consequences of their communications, so would they still do it, or would they clam up and fall silent - neither wanting to damage other races, or risk being damaged themselves? For the sake of argument I'd propose that their best strategy would be to build an automated communications system, designed to engage any species unlucky enough to catch its whispers - but to never report back to the builders. This machine would be their meme-armor. It would effectively dispose of other civilizations in cases where the exchanged memes were bad, and keep the others guessing - perhaps it would even feign cultural collapse, to divert attention elsewhere. The clever aliens could go about their happy lives, having either wiped out annoyingly talkative neighbors, or seemingly dropped off the map.
..................
It really must be in the water, or perhaps it's the 50th anniversary of SETI. Yet again I've found myself in recent days trying to answer questions about whether or not there's intelligent life elsewhere in the universe. Yet again I find myself in the role of sourpuss, or is that skeptic ? One item that actually helped focus this for me was another question on how aliens might show up brandishing their weapons and licking their lip-like-features, before squishing humanity.
Let's just go through this. Do I think there's life - recognizably familiar, reproducing, information carrying arrangements of molecules - elsewhere in the universe? I think there's an awfully good chance (but this is not a statistically robust statement). Do I think any of it's "intelligent", like wot we are? Well, I think the odds are far worse, but given the size of the universe then sure, it just may be tucked away somewhere we'll never, ever, know about. So, on the face of it this kind of kills the notion of the mother-ship arriving over suburbia and hordes of iPhone wielding creatures texting us into submission. Except...well, except that there's another way to look at things.
I'll start by saying that I know this is not an original idea. Let's take the history of life on Earth. Intelligence - in the form of machine creating, modeling, mathematically fixated organisms - has not played a big role over the past 4 billion years. Dinosaurs were fabulously successful as a type of life, a hundred million years of romping (plus all the chickens running around today), extraordinary adaptations and variations...but not a wheel, differential equation, or moon shot in sight. Humans, by really all measures, are freakish - an extraordinary and wonderful oddity. This doesn't even begin to address the issue of the microbes, ancient and incredible terraformers and survivors, but no intelligence in the way we define it.
Given all of that, I think in-the-incredibly-unlikely-event that aliens show up on our doorstep they will be no smarter than your average jellyfish. They will not have built spaceships, at least not the way we think about spaceships, with flush toilets. They might have built some kind of structure to carry them through space, much in the same way that ants build a nest, or hermit crabs snag a nice shell, but they won't be doing this as an outcome of design review, they'll be doing it instinctively. These will be organisms that have evolved to treat space much like we treat the oceans. Sailing, drifting, or zooming, when they find a useful resource (if they need such things) they make planetfall and set to work, maybe like locusts, or maybe less destructively.
Is this crazy? Maybe, but less so than the other options. There are still significant physics problems. Assuming any such life originated on a planet, then climbing out of that gravity well is always going to be tough. Perhaps this filters out all but the tiniest organisms, lofted up to the exosphere, evaporated out into space. Or perhaps it filters out all but the oddities....
Obviously I should stop drinking the water.