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I'm going to try to put into words something about our methods of hunting for alien life that has always bothered me, and I'm probably going to fail. What is i

I'm going to try to put into words something about our methods of hunting for alien life that has always bothered me, and I'm probably going to fail. What is intelligence in the context of extraterrestrial life? I posit that we have no good model for what intelligence actually is, and that it makes no sense to assume any alien lifeform would share our goals of seeking knowledge, reproduction, preservation, or "living well". These are goals tied up very much with how life on this planet evolved. What if instead of life being on a one-dimensional axis of "intelligence", each isolated biome evolves unique properties for continued existence on its own planet, with very little overlap? What makes our "intelligence" special or even desirable, outside of furthering our own evolutionarily programmed goals? Take those very specific goals away, and intelligence becomes something without a definition. This leads to a more fundamental question. What is life in the context of extraterrestrial life? How do we define success for an alien lifeform? Its continued existence? ...But in what form? Over what timescale? On what physical scale? How do we even know if any life we may find is alive or dead? I think these are not pointless philosophical questions, but something that should guide our efforts. How would we even recognize life if we found some? Are we even looking for life, or are we merely looking for life similar to Earth? Surely Earth-similar life would be much more rare than just life, but we seem to think "life" will exist on other planets with function similar to Earth, if not form. Why assume this? A lot of Earth's life's functioning is derived from how it evolved and how it's composed. I think this may be part of the answer to the Fermi Paradox. Perhaps it's a faulty assumption that intelligent life would want things like we do, and perhaps it's a faulty assumption that intelligence is even a real thing, in a context outside of Earth. Perhaps it's also faulty to assume that all life will have evolutionary goals similar to Earth's.

showerst 9y ago
One softball answer to that is that any civilization that doesn't get off of its home planet is likely to go extinct, so there's less chance of it actively modifying the environment in ways we can detect. It's also less likely to need to develop long range, high powered communications that we can detect. At the moment I think the idea that we're only looking for life that fits some definition of success is specious, we're looking for any life we can find! It happens that a big, spread out civilization that looks like us is more likely to emit something we can see, be it atmospheric, electromagnetic, etc, just by nature of being in more places in space and having a larger footprint. There are astrobiologists who spend a lot of time thinking about what life may look like, but when it comes to where to put limited resources, we start with what we know to look for (us), and go from there. You might be interested in the book 'weird life' by David Toomey, which tries to theorize about what some more exotic living things might look like in the galaxy, and expounds on some of these definitional questions.
white-flame 9y ago
I'm going to fail in my response too, since it's not my field. :) Starting from the beginning of the search, there are some gases (like oxygen) which are pretty volatile and react with many things. If volatile gases and compounds are in the atmosphere, two possibilities exist: 1) It's young, and hasn't burned through all the reactions that its raw materials would present. 2) There's some process actively creating more volatile gases, which could be a sign of something akin to life, because it doesn't drop into an expected low-entropy chemical makeup. People much smarter than I in the field would be able to distinguish more "non-living" sources like geological cycles than less-expected "maybe life" activity. But basically, if there's some life-ish process on the planet, it should affect the entire atmosphere enough to be detectable. Certainly it's only 1 way that chemical activity can be detected, because if things are bound into subterranean caverns or don't involve gases in their activity cycles, it probably wouldn't be visible in its atmospheric composition. However, this sort of search doesn't necessarily target earth-like life, but any "huh, that's strange" observance of chemical makeups, which is good. So we have one additional means of defining "life", in that it goes against the chemical entropy-reducing direction of its planetary environment; there are sustained complex active processes that aren't just raw chemical or physical potential energy releasing itself. If we find something "living", only then the question of whether or not it's "intelligent" becomes meaningful, because the only metric we currently have for that is "thinks like humans" which isn't enough to work with.
sideshowb 9y ago
I think schrodinger's entropic definition of life answers most of your questions and is general enough to transcend our own biological oddities. Still I like https://xkcd.com/638/ https://xkcd.com/638/

showerst 9y ago

One softball answer to that is that any civilization that doesn't get off of its home planet is likely to go extinct, so there's less chance of it actively modifying the environment in ways we can detect. It's also less likely to need to develop long range, high powered communications that we can detect. At the moment I think the idea that we're only looking for life that fits some definition of success is specious, we're looking for any life we can find! It happens that a big, spread out civilization that looks like us is more likely to emit something we can see, be it atmospheric, electromagnetic, etc, just by nature of being in more places in space and having a larger footprint. There are astrobiologists who spend a lot of time thinking about what life may look like, but when it comes to where to put limited resources, we start with what we know to look for (us), and go from there. You might be interested in the book 'weird life' by David Toomey, which tries to theorize about what some more exotic living things might look like in the galaxy, and expounds on some of these definitional questions.

white-flame 9y ago

I'm going to fail in my response too, since it's not my field. :) Starting from the beginning of the search, there are some gases (like oxygen) which are pretty volatile and react with many things. If volatile gases and compounds are in the atmosphere, two possibilities exist: 1) It's young, and hasn't burned through all the reactions that its raw materials would present. 2) There's some process actively creating more volatile gases, which could be a sign of something akin to life, because it doesn't drop into an expected low-entropy chemical makeup. People much smarter than I in the field would be able to distinguish more "non-living" sources like geological cycles than less-expected "maybe life" activity. But basically, if there's some life-ish process on the planet, it should affect the entire atmosphere enough to be detectable. Certainly it's only 1 way that chemical activity can be detected, because if things are bound into subterranean caverns or don't involve gases in their activity cycles, it probably wouldn't be visible in its atmospheric composition. However, this sort of search doesn't necessarily target earth-like life, but any "huh, that's strange" observance of chemical makeups, which is good. So we have one additional means of defining "life", in that it goes against the chemical entropy-reducing direction of its planetary environment; there are sustained complex active processes that aren't just raw chemical or physical potential energy releasing itself. If we find something "living", only then the question of whether or not it's "intelligent" becomes meaningful, because the only metric we currently have for that is "thinks like humans" which isn't enough to work with.

sideshowb 9y ago

I think schrodinger's entropic definition of life answers most of your questions and is general enough to transcend our own biological oddities. Still I like https://xkcd.com/638/ https://xkcd.com/638/