Way Out There

Looking back at things I've written here and eslewhere, I've realized my writting is really terrible. I guess I'll blame the (alleged) bane to literacy that is text-mesaging. I've grown so used to trying to fit ideas into such a tiny number of characters that I have difficultly talking about things in a more drawn-out and detailed way. Hrm.

Anyway, I was on the xkdc forums the other day, and I came accross a point that really irks me. Lots of people believe in extraterrestrial life, which in itself is fine, but many (those who are scientifically-minded and intelligent included) seem to think it is rationally superior to the belief that extraterrestrial does not exists. The idea is that the sheer scale of the Universe makes life elsewhere almost a certainty, because with all the trillions upon trillions of stars (and potentially planets) the odds are pretty good that life also developed somewhere besides here, right?

To lazily quote my post from the forums:

The reasoning behind this argument is fundamentally flawed. It doesn't matter how incomprehensably many planets may exist, since we don't have any clue as to what the likelihood of life developing on any given planet is. Let's say n is the total number of planets that have existed or will exist at any point in time for all eternity or until the Universe ends. I think everyone can agree that's a pretty large number. But what if the probability of life developing on a planet at any point in the planet's lifetime is 1:2n? If that's the case, then we're actually pretty lucky that any life in the Universe developed at all. Sure, with those odds maybe one or two other planets will develope life at some point in the history of the Universe, but what are the odds that they also have intelligent life, that the life forms existed at the same time as us, they have developed communications technology that we will be able to interpret and find meaningful, and they live close enough to us that such communication is possible? Nil, I'd say.

But that's just the half of it. What if the likelihood of life developing on a planet at any point in the planet's lifetime is actually 1:n²? If that's the case then we're extrodinarily lucky that we exist, the winning ten different lotteries a million times in a row kind of lucky. If this is the case then it's not just useless looking for extra-terrestrial intelligence, it's downright irrational.

Now, to be fair, maybe those numbers are all wrong. Maybe the number's more like 1:10, but that's not the point. The point is that we don't know what the numbers are. The belief that there isn't any life outside Earth is just as rational as the belief that there is. They're both just guesses at this point.