Not necessarily. As Wikipedia says, “According to the Great Filter hypothesis at least one of these steps—if the list were complete—must be improbable.” That is, if “Great Filter” means anything, it’s that one or more of the steps to achieving a technological civilization that can expand throughout the galaxy is very difficult (“improbable”).
What I’m talking about goes like this: suppose that none of the steps are very difficult. Of course, that doesn’t mean they’re instantaneous—each step takes time. You need elements other than hydrogen and helium for life, so you have to watch the supernova clock ticking until Population I stars form (maybe Pop II, but remember that this is hypothetical—let’s assume that only Pop I stars have enough “metals”). Then you need planets—but we’re seeing planets everywhere as the limits of our vision increase. Once the first replicator forms, you have to wait for evolution to grind its way up the complexity ladder (mandatory disclaimer: evolution doesn’t “prefer” higher complexity, but there is a complexity lower bound—there is literally nowhere to go but up). In this scenario, where none of the steps are improbable, but they do take time, what would the first intelligent species in a given lightcone see?
They would arrive on the scene, and they would see a young-looking universe. Their star would be among the first stars capable of supporting life. Their planetary formation would have been almost immediately followed by the first replicator (and returning to reality for a moment, we see fossilized life as far back as 1 billion years after the Earth’s formation). Their evolutionary history, while marked by giant impacts and mass extinctions, would appear relatively free of long reigns of nothing happening complexity-wise. And they would see an empty universe, and wonder where everyone else is.
Obviously, I don’t know the answer to the Fermi Paradox. But if anyone exists, someone’s got to be first. Maybe it’s us, and maybe that’s why the paradox is so baffling.
(Instead of “where are they”, I think the LW way of phrasing the paradox is “why aren’t we paperclips?”.)
That’s a very attractive scenario. But I don’t think ‘Someone had to be the first’ is sufficient to explain why we are the first. On your view, intelligent life takes some time to get going, but then is incredibly abundant for as long as stars and metals abound. On standard cosmological models, star formation will continue for some 100,000 billion years (or at minimum 1,000 billion years). Anthropically, our occurring only 14 billion years into our universe’s lifetime is then profoundly surprising. If a lot of intelligent life precedes us (and/or intelligent life is generically rare and will never be very abundant), then our location remains surprising, but a lot less so.
Your theory predicts what we see given that we evolved very early in our universe’s lifetime, but if we don’t build in our temporal location then it actually strongly predicts the opposite—that we’ll open our eyes and see a galaxy teeming with life, many tens or hundreds of billions of years after the beginning of the universe.
I don’t claim it’s sufficient, I just claim it’s possible. And while it’s true that most civilizations would see a galaxy teeming with life, somebody’s gotta be first.
Anything’s possible. If your claim is interesting, it’s because it’s probable, at least relative to its explanatory rivals.
The problem with ‘somebody’s gotta be first’ is that it’s either a fully general explanation or no explanation at all. Suppose you and a hundred billion of your friends are each assigned a distinct number between 1 and a hundred billion. You’re assigned the number 1. Should you dismiss this surprising outcome because ‘someone had to get 1’? No. Not without a lot of evidence that it’s a coincidence, anyway. The fact that someone had to get 1 only means that it was possible, on the terms on the game, for you to get 1. It doesn’t make that possibility, when it occurs, any less surprising or confusing. The goal of explaining our observations isn’t to show that they’re possible; it’s to show that they’re a lot more likely than they would have been in the absence of the explanans.
‘Someone had to win’ isn’t a full explanation on its own, no. (If it were, it would be a fully general explanation schema; ‘something had to happen’, for example, can explain any event.) Rather, ‘someone had to win’ is an explanation for an unlikely victory when you posit a large sample space. In most cases, selection bias will also play a role in the explanation—it will account for the prima facie salience or interestingness of the event.
If selection bias and the size of the sample space don’t help make you any less confused about why some X happened to you, then revisiting ‘someone had to X’ shouldn’t alleviate your confusion.
Yes, someone has to be first and this is what they would see. Or actually, this is what the first dozens or hundreds or thousands would see as without great filters you’d probably have many hundreds of species reaching an information age at around the same time but there would be a good while before they produce enough evidence to detect each other with any likelihood.
This era of galactic development though before the first civilizations become detectable to each other - on the order of a few thousands of years—is unimaginably short in terms of the time-span of the cosmos, unimaginably short even in terms of the lifetime of our own sun. It seems like tens of millions of civilizations would develop in the life-span of our Sun and its peers and yet we have to be among this very small sample at the beginning. That would be surprising.
A great filter is I suppose, equally surprising even though the mechanisms of it would maybe not be surprising.
Wouldn’t this mean that the Great Filter is behind us?
Not necessarily. As Wikipedia says, “According to the Great Filter hypothesis at least one of these steps—if the list were complete—must be improbable.” That is, if “Great Filter” means anything, it’s that one or more of the steps to achieving a technological civilization that can expand throughout the galaxy is very difficult (“improbable”).
What I’m talking about goes like this: suppose that none of the steps are very difficult. Of course, that doesn’t mean they’re instantaneous—each step takes time. You need elements other than hydrogen and helium for life, so you have to watch the supernova clock ticking until Population I stars form (maybe Pop II, but remember that this is hypothetical—let’s assume that only Pop I stars have enough “metals”). Then you need planets—but we’re seeing planets everywhere as the limits of our vision increase. Once the first replicator forms, you have to wait for evolution to grind its way up the complexity ladder (mandatory disclaimer: evolution doesn’t “prefer” higher complexity, but there is a complexity lower bound—there is literally nowhere to go but up). In this scenario, where none of the steps are improbable, but they do take time, what would the first intelligent species in a given lightcone see?
They would arrive on the scene, and they would see a young-looking universe. Their star would be among the first stars capable of supporting life. Their planetary formation would have been almost immediately followed by the first replicator (and returning to reality for a moment, we see fossilized life as far back as 1 billion years after the Earth’s formation). Their evolutionary history, while marked by giant impacts and mass extinctions, would appear relatively free of long reigns of nothing happening complexity-wise. And they would see an empty universe, and wonder where everyone else is.
Obviously, I don’t know the answer to the Fermi Paradox. But if anyone exists, someone’s got to be first. Maybe it’s us, and maybe that’s why the paradox is so baffling.
(Instead of “where are they”, I think the LW way of phrasing the paradox is “why aren’t we paperclips?”.)
That’s a very attractive scenario. But I don’t think ‘Someone had to be the first’ is sufficient to explain why we are the first. On your view, intelligent life takes some time to get going, but then is incredibly abundant for as long as stars and metals abound. On standard cosmological models, star formation will continue for some 100,000 billion years (or at minimum 1,000 billion years). Anthropically, our occurring only 14 billion years into our universe’s lifetime is then profoundly surprising. If a lot of intelligent life precedes us (and/or intelligent life is generically rare and will never be very abundant), then our location remains surprising, but a lot less so.
Your theory predicts what we see given that we evolved very early in our universe’s lifetime, but if we don’t build in our temporal location then it actually strongly predicts the opposite—that we’ll open our eyes and see a galaxy teeming with life, many tens or hundreds of billions of years after the beginning of the universe.
I don’t claim it’s sufficient, I just claim it’s possible. And while it’s true that most civilizations would see a galaxy teeming with life, somebody’s gotta be first.
Anything’s possible. If your claim is interesting, it’s because it’s probable, at least relative to its explanatory rivals.
The problem with ‘somebody’s gotta be first’ is that it’s either a fully general explanation or no explanation at all. Suppose you and a hundred billion of your friends are each assigned a distinct number between 1 and a hundred billion. You’re assigned the number 1. Should you dismiss this surprising outcome because ‘someone had to get 1’? No. Not without a lot of evidence that it’s a coincidence, anyway. The fact that someone had to get 1 only means that it was possible, on the terms on the game, for you to get 1. It doesn’t make that possibility, when it occurs, any less surprising or confusing. The goal of explaining our observations isn’t to show that they’re possible; it’s to show that they’re a lot more likely than they would have been in the absence of the explanans.
I would be surprised because that violates the pigeonhole principle.
(Yeah, I’m a programmer.)
Isn’t “someone had to win” the rationalist explanation for most lottery winners?
‘Someone had to win’ isn’t a full explanation on its own, no. (If it were, it would be a fully general explanation schema; ‘something had to happen’, for example, can explain any event.) Rather, ‘someone had to win’ is an explanation for an unlikely victory when you posit a large sample space. In most cases, selection bias will also play a role in the explanation—it will account for the prima facie salience or interestingness of the event.
If selection bias and the size of the sample space don’t help make you any less confused about why some X happened to you, then revisiting ‘someone had to X’ shouldn’t alleviate your confusion.
I see. Good answer.
Yes, someone has to be first and this is what they would see. Or actually, this is what the first dozens or hundreds or thousands would see as without great filters you’d probably have many hundreds of species reaching an information age at around the same time but there would be a good while before they produce enough evidence to detect each other with any likelihood.
This era of galactic development though before the first civilizations become detectable to each other - on the order of a few thousands of years—is unimaginably short in terms of the time-span of the cosmos, unimaginably short even in terms of the lifetime of our own sun. It seems like tens of millions of civilizations would develop in the life-span of our Sun and its peers and yet we have to be among this very small sample at the beginning. That would be surprising.
A great filter is I suppose, equally surprising even though the mechanisms of it would maybe not be surprising.