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Thread: What do you think is the most likely explanation for the Fermi paradox?

  1. #511
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    Quote Originally Posted by Noclevername View Post

    Suppose we do come across an unknown form of life or something similar to life, with no commonality to our own. How would we know to identify it unless we had a more general and broad definition of the terms life and lifelike, than what we currently use for ourselves?
    I'm not sure that we'd be able to identify life if it were to be found; one of the definitions of life I've seen bruited about lately is "reproduces and evolves"; NASA's is "a self-sustaining chemical system capable of Darwinian evolution"1; that latter bit is obviously impossible to determine without long-term observation.







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    1: http://www.bbc.com/earth/story/20170...-all-are-wrong
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  2. #512
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    Quote Originally Posted by swampyankee View Post
    I'm not sure that we'd be able to identify life if it were to be found; one of the definitions of life I've seen bruited about lately is "reproduces and evolves"; NASA's is "a self-sustaining chemical system capable of Darwinian evolution"1; that latter bit is obviously impossible to determine without long-term observation.
    So NASA's definition includes only chemical systems. A wide yet limited classification. As for evolution, if it reproduces generationally in any way but perfectly exact, it's going to undergo natural selection, so it's evolving.

    But... what would you call a species that has ceased natural reproduction? They may still be biological, but they skirt the definition.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

  3. #513
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    Quote Originally Posted by Noclevername
    Bunkum.
    The logic I gave, which you requested .. was not bunkum. You (& NASA) are assuming you already know what 'ET life' is, and designing tests around that assumed knowledge. So only that assumption is under test .. yet the fact is that assumption has no objective basis in reality other than in Earth's biosphere. It is thus not a test of what may exist in some other non-earthly environment.

    Quote Originally Posted by Noclevername
    The problem is, since we don't know what ET life may or may not be like, we start with what we know works,
    .. therefore, they're testing what we know works in Earth's environment .. which is obviously majorly different from an Enceladus, Titan (etc) environment.

    Quote Originally Posted by Noclevername
    and branch off from there. Start with detectable specifics, and then widen our search. If biological life under Earth conditions has certain characteristics, we extrapolate
    'Extrapolation' assumes more than a singular datapoint.
    Quote Originally Posted by Noclevername
    .. from known patterns such as water, and expand to other solvents, etc. It's a known, viable exploratory method; similar to what was used in WWII to search for lost ships or downed aircraft; Start from the last known location, and look further afield methodically.
    Tell me how that differs from the religious search for 'the Holy Grail' .. or the origin of the Shroud of Turin.

    Quote Originally Posted by Noclevername
    Suppose we do come across an unknown form of life or something similar to life, with no commonality to our own. How would we know to identify it unless we had a more general and broad definition of the terms life and lifelike, than what we currently use for ourselves?
    The debate here is about how broad to make that definition. I've already stated my case .. we start by looking at the new landscape and take it from there based on what we observe .. that's how science is done .. and not in advance of the observation (using targetted speculation as the sole basis).
    No need for Levin's Viking biological (metabolic) experiments in any of that approach.

  4. #514
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    Quote Originally Posted by swampyankee View Post
    I'm not sure that we'd be able to identify life if it were to be found;
    I think it depends entirely on what we observe at the time .. I believe .. (yep its a belief .. but readily testable in an Earthly biosphere) .. that humans are pretty good at noticing differences in any given landscape (figurative, or literal in sense). So I'm confident that sense, (coupled with an active scientifically disciplined, enquiring mind), is the key focus .. and not assumptions about 'what likely must exist'. There is, unfortunately, a big cost involved in taking the latter approach .. have we not learned from history (aka objective evidence)?

    Quote Originally Posted by swampyankee
    one of the definitions of life I've seen bruited about lately is "reproduces and evolves"; NASA's is "a self-sustaining chemical system capable of Darwinian evolution"1; that latter bit is obviously impossible to determine without long-term observation.
    I don't think I'd necessarily dismiss that. If we observe something which distinguishes itself from the backdrop landscape, which appears to be 'thriving' (in a self-sustaining way), we can then measure a sample's accuracy of self-replication (an observable measure). Its then pretty difficult to escape a conclusion of Darwinian Evolution under such circumstances, I think(?)







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    1: http://www.bbc.com/earth/story/20170...-all-are-wrong[/QUOTE]

  5. #515
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    Contextualising this sub-conversation; the Fermi paradox relies, first and foremost, on the observation of that we first have to recognise non-earthly 'life' .. thus far we haven't succeeded in doing this .. so perhaps this because we don't even know what such 'life' might look like ...

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    Quote Originally Posted by Selfsim View Post
    The logic I gave, which you requested .. was not bunkum. You (& NASA) are assuming you already know what 'ET life' is, and designing tests around that assumed knowledge.
    No. As I already pointed out, your statement is not a correct assessment.

    We are STARTING with life As We Know It because we need a starting point. We can't wave our arms and get all the universe's data, we have to design tests and equipment to do those tests.

    So only that assumption is under test .. yet the fact is that assumption has no objective basis in reality other than in Earth's biosphere. It is thus not a test of what may exist in some other non-earthly environment.

    .. therefore, they're testing what we know works in Earth's environment .. which is obviously majorly different from an Enceladus, Titan (etc) environment.

    'Extrapolation' assumes more than a singular datapoint. Tell me how that differs from the religious search for 'the Holy Grail' .. or the origin of the Shroud of Turin.

    The debate here is about how broad to make that definition. I've already stated my case .. we start by looking at the new landscape and take it from there based on what we observe .. that's how science is done .. and not in advance of the observation (using targetted speculation as the sole basis).
    No need for Levin's Viking biological (metabolic) experiments in any of that approach.
    All the rest of what you claim here is false assumptions based on your original untrue premise. Garbage in, garbage out.
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  7. #517
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    Quote Originally Posted by Noclevername View Post
    .. We are STARTING with life As We Know It because we need a starting point. We can't wave our arms and get all the universe's data, we have to design tests and equipment to do those tests.
    Re: emboldened words .. and those words verify my point .. its a hunt for the Holy Grail.

    Quote Originally Posted by Noclevername
    All the rest of what you claim here is false assumptions based on your original untrue premise. Garbage in, garbage out.
    I am not playing the logic game here .. I'm playing the scientific game .. which doesn't require 'true' or 'untrue posits' .. only the objective evidence of known life's context ... which is earth's environment ... (and not something other than that).

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    Selfsim, I would be interested in hearing a detailed discussion from you on the best way to find exo-life. You are not satisfied with any current means of doing so, so the ball is in your court.

    How would YOU go about searching for life on Mars, Titan, etc.?

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    Quote Originally Posted by Selfsim View Post
    Re: emboldened words .. and those words verify my point .. its a hunt for the Holy Grail.

    I am not playing the logic game here .. I'm playing the scientific game .. which doesn't require 'true' or 'untrue posits' .. only the objective evidence of known life's context ... which is earth's environment ... (and not something other than that).
    You point is (still) false.

    Attribute whatever motives and beliefs to me you like, my (and scientist's) goal is the expansion of scientific knowledge. Whether or not it involves finding life ...of any definition.
    "I'm planning to live forever. So far, that's working perfectly." Steven Wright

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    SETI is roughly analogous to looking for one's lost keys under the streetlight. I fear that we may be limiting the search for life in a similar way, with, for example, the "search for the water."

    Leaving that aside, in a low-energy environment, it's not impossible that metabolism and reproduction are so slow that they'd not be noticed in the time span of a short-lived probe. Reportedly, some of the deep underground microbes observed on Earth have metabolic rates that are so low it's nearly impossible to tell if they're alive (https://microbewiki.kenyon.edu/index..._Igneous_Rocks).
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  11. #521
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    Quote Originally Posted by Jens View Post

    Quote Originally Posted by Colin Robinson View Post
    Does science progress just by generalised surveys? Or also by trying to answer specific questions?
    No, not necessarily. I think the generally accepted idea in funding today is that there should be a balance of mission-driven projects and curiosity-driven projects.



    Sent from my iPhone using Tapatalk
    Is a "mission-driven" project the more generalised sort, and "curiosity-driven" the more specific, or is it the other way around? Anyway, I agree that there should be a balance.

  12. #522
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    Quote Originally Posted by swampyankee View Post
    SETI is roughly analogous to looking for one's lost keys under the streetlight. I fear that we may be limiting the search for life in a similar way, with, for example, the "search for the water."
    There are many different observations going on. If life exists within our limited view, it's possible one or another project might find it without looking for it specifically.

    But I always thought the Fermi "paradox" was about life finding us.
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    Quote Originally Posted by swampyankee View Post
    SETI is roughly analogous to looking for one's lost keys under the streetlight.
    I share that concern, at least I have shared it.

    SETI in the past has meant trying to detect deliberately sent radio signals from nearby stars. An argument for doing this was that the probability of a positive result might be small, but it was arguably higher than zero, and it seemed like the only feasible way of searching for ETI. For a decade or so after Viking, that sort of radio search even seemed like the only feasible way of searching for extraterrestrial life (intelligent or not).

    It was indeed like looking for keys under the streetlight on the basis that there a slim chance they might be there...

    And speaking of "eerie silence", as Paul Davies has, seems to me like speaking of an eerie absence of keys, in that little circle of well-lit pavement.

    I understand though that the SETI Institute is moving towards different methods of searching — trying to identify which exo-planets may be habitable, and then looking for a broader range of signs of habitation than deliberately sent signals only...

    I fear that we may be limiting the search for life in a similar way, with, for example, the "search for the water."
    Yes, I agree that too much emphasis on "search for the water" has been a limitation on astrobiology.

    I think the Cassini-Huygens mission, and the recently approved Dragonfly project show a needed shift towards more interest in carbon compounds, rather than exclusive preoccupation with H2O.

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    Quote Originally Posted by Noclevername View Post
    You point is (still) false.

    Attribute whatever motives and beliefs to me you like, my (and scientist's) goal is the expansion of scientific knowledge. Whether or not it involves finding life ...of any definition.
    Well the motive and belief you just expressed there, differs markedly from the purpose of development of an overall scientific theory of life .. which is of course, to make predictions from objective testing.
    Knowledge gained in the process of doing that, is of keen interest to philosophers ... Who are of course, still trying to figure out what 'knowledge' actually is .. so this 'hunt' continues to sustain their heady, lofty, meaninglessness in that regard.

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    Quote Originally Posted by swampyankee
    SETI is roughly analogous to looking for one's lost keys under the streetlight.
    .. which assumes, of course, that another set of keys exist (or, 'is true') and presumes that they're actually lost (or, 'is true').
    ('Cept there ain't no 'truths' in science ..)

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    Quote Originally Posted by Roger E. Moore View Post
    Selfsim, I would be interested in hearing a detailed discussion from you on the best way to find exo-life. You are not satisfied with any current means of doing so, so the ball is in your court.

    How would YOU go about searching for life on Mars, Titan, etc.?
    Why am I compelled to go searching for life elsewhere in the first place?

    What's wrong with just exploring and cataloguing whatever there is to observe and catalogue?
    After all, that's what got us to the point we're at in science in the first place! Why not continue doing that?

    Doing so is not dependent on the assumed existence of life elsewhere .. whereas deliberately searching for such a thing ... is!

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    Quote Originally Posted by Selfsim View Post
    Why am I compelled to go searching for life elsewhere in the first place?

    What's wrong with just exploring and cataloguing whatever there is to observe and catalogue?
    After all, that's what got us to the point we're at in science in the first place! Why not continue doing that?

    Doing so is not dependent on the assumed existence of life elsewhere .. whereas deliberately searching for such a thing ... is!
    ET can help with the back catalogues of life on earth hopefully
    Last edited by alromario; 2019-Jul-02 at 07:41 AM.

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    Quote Originally Posted by Colin Robinson View Post
    Is a "mission-driven" project the more generalised sort, and "curiosity-driven" the more specific, or is it the other way around? Anyway, I agree that there should be a balance.
    Sorry, I guess itís jargonish. Itís the opposite, as mission-driven means funds that are given for a specific finding, like to find the Higgs boson for example. While curiosity-driven means, we give you the funding and you decide what you want to do with it according to your own curiosity.
    As above, so below

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    Quote Originally Posted by Noclevername View Post
    But I always thought the Fermi "paradox" was about life finding us.
    I thought it was about both, both why they havenít come to us and why we havenít detected them.
    As above, so below

  20. #530
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    Quote Originally Posted by Selfsim View Post
    Why am I compelled to go searching for life elsewhere in the first place?

    What's wrong with just exploring and cataloguing whatever there is to observe and catalogue?
    After all, that's what got us to the point we're at in science in the first place! Why not continue doing that?

    Doing so is not dependent on the assumed existence of life elsewhere .. whereas deliberately searching for such a thing ... is!
    Because it would be boring otherwise.

    There is good reason to assume life exists elsewhere, the universe is vast and filled with many worlds similar to our own.

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    Quote Originally Posted by Selfsim View Post
    Doing so is not dependent on the assumed existence of life elsewhere .. whereas deliberately searching for such a thing ... is!
    I disagree with your characterization of the issue, but after some thought have realized the discussion is both pointless and off topic. We are talking about why we aren't seeimg any aliens, not why we should not be looking for them. I will go back to wondering Where They Are.

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    Hi Roger,

    Hmm, Selfsim's ideas would make a great thread where he could better explain. But they are germane to the discussion of why we might not see life ŗ la Fermi paradox.

    That's if I get what he's talking about. lol

  23. #533
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    Quote Originally Posted by 7cscb View Post
    Hmm, Selfsim's ideas would make a great thread where he could better explain. But they are germane to the discussion of why we might not see life ŗ la Fermi paradox.

    That's if I get what he's talking about. lol
    I admit you have a point. However I also think that I will drop my complaint and talk about something else. It is better for all that way.

  24. #534
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    Quote Originally Posted by Selfsim View Post
    Well the motive and belief you just expressed there, differs markedly from the purpose of development of an overall scientific theory of life .. which is of course, to make predictions from objective testing.
    Knowledge gained in the process of doing that, is of keen interest to philosophers ... Who are of course, still trying to figure out what 'knowledge' actually is .. so this 'hunt' continues to sustain their heady, lofty, meaninglessness in that regard.
    So you think knowledge is meaningless? Interesting interpretation. As for testing, I already mentioned that in post #516. We cannot test without having designed the tests, and we cannot make predictions without data. To accomplish those things we need goals.


    As this is degenerating into another Philosophy of Science argument, I'll go back to talking about the topic of the thread.
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    Quote Originally Posted by Noclevername View Post
    So you think knowledge is meaningless? Interesting interpretation. As for testing, I already mentioned that in post #516. We cannot test without having designed the tests, and we cannot make predictions without data. To accomplish those things we need goals.
    It seems to me clearly that Selfsim was saying that they feel we are going about planetary studies in the same way, and a person who thinks knowledge is meaningless would not argue that. Somehow there is a misunderstanding happening here. If you even read the sentence before the one you responded to, they were talking about how to build a theory of life. If they believed that knowledge is meaningless, why would they say that?
    As above, so below

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    Quote Originally Posted by Jens View Post
    It seems to me clearly that Selfsim was saying that they feel we are going about planetary studies in the same way, and a person who thinks knowledge is meaningless would not argue that. Somehow there is a misunderstanding happening here. If you even read the sentence before the one you responded to, they were talking about how to build a theory of life. If they believed that knowledge is meaningless, why would they say that?
    I will let Selfsim clarify their own words.
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    Quote Originally Posted by kzb View Post
    (2) We have found life on Mars, and it was announced by the president of the United States on TV. This is a good example of the problems I anticipate.
    If you're referring to ALH84001, (1) No, it was not established that life was found on Mars, and (2) President Clinton announced the possible discovery of life on Mars, subject to peer review. As peer review developed, various issues were discovered with the initial claims.

    If you're not talking about ALH84001, then please provide references to whatever you are talking about.

    I have read, though, that all the attention given to ALH84001, and the perception that it may have demonstrated life from Mars may have substantially helped backing of later Mars missions. It's an interesting issue: Missions are not flown just because of what scientists may want, but need political support from non-scientists and actually be interesting to at least some significant fraction of the public. Dry science just for the sake of science only goes so far to get missions flying, and without the missions, no science will be done.

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    Maybe the robot civilizations that eventually take over all technological planets have been in communication with each other and have all agreed to keep their biological inhabitants isolated to maintain peace and security.

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    Quote Originally Posted by Van Rijn View Post
    If you're referring to ALH84001, (1) No, it was not established that life was found on Mars, and (2) President Clinton announced the possible discovery of life on Mars, subject to peer review. As peer review developed, various issues were discovered with the initial claims.

    If you're not talking about ALH84001, then please provide references to whatever you are talking about.

    I have read, though, that all the attention given to ALH84001, and the perception that it may have demonstrated life from Mars may have substantially helped backing of later Mars missions. It's an interesting issue: Missions are not flown just because of what scientists may want, but need political support from non-scientists and actually be interesting to at least some significant fraction of the public. Dry science just for the sake of science only goes so far to get missions flying, and without the missions, no science will be done.
    I don't remember it like that at all. I recall President Clinton announcing the discovery of life on Mars. And he was put up there at the request of NASA.

    Whilst I go along with what you say about publicity, the later backtracking must've been embarrassing for all concerned.

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    Quote Originally Posted by kzb View Post
    .. Whilst I go along with what you say about publicity, the later backtracking must've been embarrassing for all concerned.
    Let's also not forget about the notorious Richard Hoover episode who, in 2011, published a 'paper' in the crank Journal of Cosmology, wherein he claimed evidence in meteorites that life on Earth came from space, in this case, in the form of comet debris. (He's apparently made similar claims six times to date!)

    Then again in the same crank Journal, a 'Rhawn Joseph' published an article in January 2014, concluding that the martian (in situ) rock, dubbed 'Pinnacle Island', was in fact, a living organism.

    The pattern seems clear ... the fixation with 'life must be out there', (which of course provokes the Fermi Paradox), when combined with marginal scientific qualifications, (a BSc in Hoover's case), leads towards pareidolia driven delusions, a life of pseudoscientific crankdom, which then serves to perpetuate the accompanying fixation with the Paradox too (ie: Fermi's) ... which really never was one at all anyway(?)

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