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Thread: Evidence for ET is mounting daily, but not proven.

  1. #631
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    Quote Originally Posted by Paul Wally View Post
    Occam's Razor is not a judge of truth. Even if there is a geological explanation, just the possibility that the methane plumes could possibly be of biological origin makes it a worthy hypothesis to follow up on. If we are trying to find life then we should follow up on the clues that could possibly lead us there. And if it turns out that the plumes are of geological origin then so be it. But not pursuing a line of investigation simply because there is a simpler boring explanation, that may possibly be false, doesn't make much sense to me.
    I'm curious as to Colin's answer, but thanks for the simple yes or no response.

  2. #632
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    Methane on Mars - my understanding is that, in humanity's experience, methane is produced either by volcanoes, or a by product of life. Its half life is only about 300 years so that the presence of it in mars atmosphere is intriguing, especially taken with the evidence for water, both past and present, however Mars has been a very volcanically active planet and possibly is today.

    could it be volcanism creating the methane plumes on Mars? sure. but it could also be life. there are plenty of other indicators of the potential for life there to go and find out!

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    Quote Originally Posted by eburacum45 View Post
    Since we don't actually know for sure that the Ediacara biota had the same biochemistry as ourselves,we should really only consider the morphology. The morphology was unlike anything we are familiar with.

    Similarly we should expect any extraterrestrial life to be unlike anything we are familiar with. The fossil record shows that there is a very large range of possible lifeforms and a very large range of possible environments which can support life. So far we have only encountered a tiny fraction of those possible lifeforms and possible environments.
    Big difference between the range of conditions life can adapt to given time and exploitable energy to take advantage of, and the range of conditions suitable for the formation of life. Finding life in a large range of habitats says very little about where we might expect life to form, and that is much more important than conditions which we may think or can demonstrate that life can adapt to.

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    Ancient methane could also be released from methane clathrate ices that are sublimating after being exposed by erosion. The same reason methane is detected in comets.

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    Quote Originally Posted by R.A.F. View Post
    Are there no other explanations for the presence of methane on Mars?
    There are other possible explanations, yes other hypotheses consistent with the data.

    What Paul Wally said, is how I see it also...

    Quote Originally Posted by Paul Wally View Post
    ...just the possibility that the methane plumes could possibly be of biological origin makes it a worthy hypothesis to follow up on. If we are trying to find life then we should follow up on the clues that could possibly lead us there. And if it turns out that the plumes are of geological origin then so be it.
    In any case, the presence of methane in Mars' atmosphere requires some explanation, because it is an anomaly, in the sense that methane can't just hang about indefinitely in the sort of atmosphere Mars has.

    A possibly relevant quote from the biologist Lynn Margulis (one of the originators of the Gaia Hypothesis) back before the methane was found. She was being interviewed by Stewart Brand of the CoEvolution Quarterly, and she explained why she thought there was no life on Mars:

    Margulis:You see, there are no reduced compounds in the presence of the oxidized ones. Which is our clue. Everything's essentially oxidized.
    SB: If there were life you'd look for what gases?
    Margulis:You'd look for ammonia, methane, hydrogen, or hydrogen sulfide or any of these things that are flagrant contradictions in the presence of oxygen and CO2...
    Source: Steward Brand (ed); Space Colonies; Penguin 1977; page 124.

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    Quote Originally Posted by John Jaksich View Post
    I have often felt that way, also---but when I have looked closer at my lines of reasoning--I have come to realize that there are occasions when one tends to let "emotional" reasoning sway there better judgement. Don't get me completely wrong---there is truth to your statement but a simple explanation entails that the further investigation the phenomenon could involve complexities of which you are currently inferring and possibly (?) hoping to be true.

    My personal advice is to not give up but don't completely give into your emotions.
    Do you think that emotion wants life beyond Earth to exist, while reason is on the other side?

    I would question that.

    About 100 years, Alfred Russel Wallace (one of the pioneers of the theory of evolution) wrote a book called Man's Place in the Universe, where he said that the idea of many inhabited worlds "would imply that man is... of no importance".

    Conversely, if Earth is the only world with life, and we humans are the dominant life form on it, that makes the human race a big frog in a small pond.

    Maybe this is why many humans are reluctant to take seriously the idea of life beyond Earth?

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    Quote Originally Posted by Colin Robinson View Post
    Do you think that emotion wants life beyond Earth to exist, while reason is on the other side?

    I would question that.

    About 100 years, Alfred Russel Wallace (one of the pioneers of the theory of evolution) wrote a book called Man's Place in the Universe, where he said that the idea of many inhabited worlds "would imply that man is... of no importance".

    Conversely, if Earth is the only world with life, and we humans are the dominant life form on it, that makes the human race a big frog in a small pond.

    Maybe this is why many humans are reluctant to take seriously the idea of life beyond Earth?

    Emotions are what they are---electrochemical impulses from certain parts of the brain to whatever response that may be eliciting them--and for the most part (from what I understand) impulsive.

    Individuals for the most part (IMO) may come in two (?) flavors: those who will do the fight/flight response (since our ancestors had to learn to fend for themselves from large predators). . . . and those who have learned to become more cerebral (and thus mindful of their surroundings) . . . thus think before acting on impulse (as cited above).

    Because of that notion (cited above) those individuals may not completely understand the implications of their own place in the cosmos.

    In regards to A. R. Wallace's work --I had heard of him but have yet to read his work and do know that he was a contemporary of Darwin's. His opinion, conclusions and data cited in his book are probably (?) far-reaching and (?) correct . . .


    My observations of humanity (although I am not a behavioral biologist--nor psychologist) tell me that we (humanity) as a species will still evolve as long as we do not wipe ourselves off the planet . . . and the reason for many individuals ambivalence for ET or ETI is because we (?) are much too wrapped up with our own lives (and believe we are the center of the Universe . . . still).

    We are currently hard-wired to respond emotionally. . . first . . . and if a wiser head prevails . . . stop, think, weigh the options (?) and respond.

    Those more enlightened few do this everyday and probably on the drop of dime (if you can pardon the expression?).

    All the best

    John

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    Regarding the emotional aspect, I think a lot of people share my stance: I really, really want there to be life out there, and I really want to know for certain that there is life out there. However, above all else I want the truth, even if it isn't the truth I hoped for. I don't want to pretend that something is evidence when it is not. I will not grasp at straws!

    I actually feel hatred for the sort of UFO proponent who deliberately mischaracterises skeptics such as myself as being closed-minded and opposed to the idea of there being life. We are not in denial; when real evidence is found, it will be impossible to deny.

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    Quote Originally Posted by transreality View Post
    ...the symmetry of the ediacaran is the same degree of symmetry as just about any leaf you may look at. They don't have the strict bilateral symmetry of alot of animalia, but then they are most likely to be some sort of organism derived from algae.
    Quite. I've seen this sort of symmetry a lot in botanical contexts. Perhaps if these creatures developed into mobile animal-like forms we might have seen animals that look like plants, and vice versa.
    Here's an image I've made of an imaginary 'animal' that shows plant-like characteristics, including an alternating morphological pattern
    http://www.orionsarm.com/im_store/leafant.JPG
    there aren't any extant animals I can think of with this sort of morphology, but they may emerge on other worlds.

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    Quote Originally Posted by John Jaksich View Post
    In regards to A. R. Wallace's work --I had heard of him but have yet to read his work and do know that he was a contemporary of Darwin's. His opinion, conclusions and data cited in his book are probably (?) far-reaching and (?) correct . . .
    Wallace was undoubtedly a great scientist, one of the pioneers of modern biology.

    Regarding his book Man's Place in the Universe, some of the ideas in it are still widely accepted (though not beyond all debate), e.g. the idea that the Solar System has a "temperate zone", basically meaning the same as "habitable zone" or "Goldilocks zone".

    On the other hand, Wallace argued (or should I say speculated) that life may not be possible in the Milky Way Galaxy anywhere except at or near its center.

    At the time, many good astronomers thought that's where our Solar System was. And Wallace thought it unlikely to be a coincidence that the only known inhabited world was in such a special cosmic location…

  11. #641
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    Quote Originally Posted by Colin Robinson View Post
    There are other possible explanations, yes – other hypotheses consistent with the data.

    What Paul Wally said, is how I see it also...
    So you made a conscious, subjective decision as to which explanation you will accept?


    How is that not "cherry picking" the data??

  12. 2011-Oct-06, 09:24 PM

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    Quote Originally Posted by R.A.F. View Post
    So you made a conscious, subjective decision as to which explanation you will accept?


    How is that not "cherry picking" the data??
    Colin Robinson and Paul Wally talked about following up possibilities, not choosing beliefs.

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    Quote Originally Posted by Paul Beardsley View Post
    Colin Robinson and Paul Wally talked about following up possibilities, not choosing beliefs.
    Yet that is exactly what they did...is there any mention of a geologic explanation before I forced the issue??

    Nope...cherry picking, plain and simple.

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    Quote Originally Posted by R.A.F. View Post
    Are there no other explanations for the presence of methane on Mars?
    Of course there are. That is what "consistent with" means; it is one possible explanation.

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    Quote Originally Posted by R.A.F. View Post
    So you made a conscious, subjective decision as to which explanation you will accept?


    How is that not "cherry picking" the data??
    Nobody is accepting anything. The hypothesis will only be accepted as true when conclusive evidence is found, e.g. if microbes are found. In the mean time
    there is no acceptance, presumption, belief etc. I think, this has been the problem all along; hypothesis is being equated with belief.

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    My error for not making myself clear. 1st off, I knew the answer to the question before I asked it. I wanted to see what reaction It would illicit. I was not disappointed.

    2nd, when you have 2 completely different explanations for the same phenomena, it isn't very forthcoming to not mention both when discussing the phenomena.

    3rd, there was no mention of a geological explanation until I "asked" if there were any other explanations besides life that would explanation the phenomena.


    ..and with that, I'm out of this thread...it ain't worth arguing about.

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    Quote Originally Posted by Strange View Post
    Of course there are. That is what "consistent with" means; it is one possible explanation.
    Can you link or reference a respectable source that supports this interpretation of "consistent with?"
    (or at the least clarify this statement so that it is "consistent with" standard understandings. - to my reading, "consistent with" states or implies nothing about alternate possibities or potentialities.)

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    Quote Originally Posted by Paul Wally View Post
    Nobody is accepting anything. The hypothesis will only be accepted as true when conclusive evidence is found, e.g. if microbes are found. In the mean time
    there is no acceptance, presumption, belief etc. I think, this has been the problem all along; hypothesis is being equated with belief.
    Properly qualified remarks are rarely misunderstood or misinterpreted.

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    Quote Originally Posted by Trakar View Post
    Can you link or reference a respectable source that supports this interpretation of "consistent with?"
    (or at the least clarify this statement so that it is "consistent with" standard understandings. - to my reading, "consistent with" states or implies nothing about alternate possibilities or potentialities.)
    I think it is quite clear in this context what "consistent with" means. It means that the available evidence does not contradict the hypothesis. It doesn't then require a great conceptual leap to understand that a limited set of evidence can be consistent with a number of different, even conflicting, hypotheses. Ever, heard of a crucial experiment? It is an experiment exactly designed to decide between different explanations of the same data. The case of the methane plumes (data) requires something like a crucial experiment that would decide between different explanations. I think at the moment it is safe to say that we don't know whether the methane is produced by living organisms or some other means, and this will require further observations that will decide between the different hypotheses.
    Last edited by Paul Wally; 2011-Oct-07 at 09:10 AM.

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    Quote Originally Posted by Trakar View Post
    Properly qualified remarks are rarely misunderstood or misinterpreted.
    I strongly suspect that this is one of those rare cases.

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    Quote Originally Posted by Paul Beardsley View Post
    Regarding the emotional aspect, I think a lot of people share my stance: I really, really want there to be life out there, and I really want to know for certain that there is life out there. However, above all else I want the truth, even if it isn't the truth I hoped for. I don't want to pretend that something is evidence when it is not. I will not grasp at straws!

    I actually feel hatred for the sort of UFO proponent who deliberately mischaracterises skeptics such as myself as being closed-minded and opposed to the idea of there being life. We are not in denial; when real evidence is found, it will be impossible to deny.
    I'd agree that if there is extraterrestrial life close enough to detect, and if the effort is made to find it, it will one day be as undeniable as the presence of lichen in Antarctica.

    I'd suggest, though, that its discovery may involve several steps, like the discovery of the element helium in the 19th century -- first a bright yellow line in the solar spectrum, which some thought indicated a new element, but was hardly undeniable proof of one; then a few years later someone found the same bright line in a lava spectrum on Earth; and then finally the undeniable stage, when helium was successfully isolated in a laboratory...

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    Quote Originally Posted by Trakar View Post
    Can you link or reference a respectable source that supports this interpretation of "consistent with?"
    (or at the least clarify this statement so that it is "consistent with" standard understandings. - to my reading, "consistent with" states or implies nothing about alternate possibities or potentialities.)
    You are right. I probably rather overstated the case. (I was going to write something much longer but it was getting late).

    I was intending to contrast "consistent with" and a word like "confirms" (for example). If someone said that something (e.g. methane) "confirmed" the existence of life then they would be effectively ruling out other explanations (and, one would hope, relying on a lot of other evidence beside that). Saying that it is "consistent with" life says nothing about other possible explanations; it doesn't rule them out and doesn't guarantee there are others. But it certainly allows others.

    I don't see why someone discussing one possibility has to, every time, list every other possibility as well. Especially in an informal context and especially when they are using cautious language such as "consistent with", "may" and "possible". I was just (over?) reacting to the way such statements are often met with "prove it" or "what about X as a possibility". I agree such a response is appropriate if someone were to say "there is life on planet xxx" but not just because they are discussing possibilities.

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    Quote Originally Posted by Colin Robinson View Post
    Do you think that emotion wants life beyond Earth to exist, while reason is on the other side?
    I think it depends on the individual (and, perhaps their cultural background and values).

    About 100 years, Alfred Russel Wallace (one of the pioneers of the theory of evolution) wrote a book called Man's Place in the Universe, where he said that the idea of many inhabited worlds "would imply that man is... of no importance".
    I don't understand that idea at all. My feeling about the discovery of any sort of life (simple or intelligent) elsewhere, is one of great excitement about the new areas of understanding it would open up. I don't see how it would change us; we would still be exactly who we are now.

    Conversely, if Earth is the only world with life, and we humans are the dominant life form on it, that makes the human race a big frog in a small pond.
    I don't know. Doesn't leave us exactly the same but in a much, much bigger pond?

    Maybe this is why many humans are reluctant to take seriously the idea of life beyond Earth?
    It may account for some. Who knows whether it is a few, many, or most.

  25. #654
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    Quote Originally Posted by R.A.F. View Post
    <snip>
    My error for not making myself clear. 1st off, I knew the answer to the question before I asked it. I wanted to see what reaction It would illicit. I was not disappointed.
    R.A.F.

    Chill with the attitude. People are having a friendly discussion about possibilities and speculations. No one seems to be advocating any particular non-mainstream ideas. Don't 'test' people as to whether they are matching some expectation you have of their behavior. If you want to participate in the discussion, then actually participate. If that's not to your liking, then maybe you should stay out of thread.
    Last edited by Swift; 2011-Oct-07 at 04:47 PM. Reason: 'Snip' quote for emphasis
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    I just want to add this, then I think I'm more or less done with this topic again.

    Observation: Methane on Mars...
    a) Hypothesis: ...indicates life.
    b) Hypothesis: ...indicates volcanic activity.
    c) Hypothesis: ...indicates "recently" exposed methane ice.
    d) Hypothesis: ...indicates some other phenomenon we haven't observed yet.

    While the highly improbable but highly desirable Hypothesis A would be the ultimate in discoveries, it in no way diminishes the importance and "Wanna know right now; when does the probe get there? Get it there faster, NASA!" factor of all three other possibilities.

    Just sayin'.
    "Words that make questions may not be questions at all."
    - Neil deGrasse Tyson, answering loaded question in ten words or less
    at a 2010 talk MCed by Stephen Colbert.

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    Actually, I take that back, slightly. I do have one more thing to say for the moment.

    Quote Originally Posted by Strange View Post
    I don't understand that idea at all. My feeling about the discovery of any sort of life (simple or intelligent) elsewhere, is one of great excitement about the new areas of understanding it would open up. I don't see how it would change us; we would still be exactly who we are now.
    I do. See how it would change us, I mean.

    Think back... The (widespread) knowledge that the sky isn't an overturned bowl changed us forever. The repeated discoveries that we're not really the center of anything in time and space, except our own ignorance, helped bring about radical and progressive changes in how we think about ourselves and how we interact with the world. Changes that were invariably met with a great deal of kicking, screaming, upheaval and death (both real and threatened). A very large fraction of the world's population is wailing incessantly over the notion that we've distant common ancestry with every other critter on the planet. We're still choking on the notion that we've common ancestry with ourselves.

    If scientific discoveries have not changed us, why all the fuss?

    No, our science is dragging us into the future by the scruffs of our necks, sweeping along the unwilling with each next discovery that reveal how we're a much smaller player in a much _much_ larger universe than we've ever imagined possible. This is necessary, if uncomfortable and humbling, and ultimately the very best thing for us.

    ... I just think it's important to let the science educate us in its time, and not anticipate its revelations.
    Last edited by Moose; 2011-Oct-07 at 05:22 PM. Reason: Grammar. Grampar, too.
    "Words that make questions may not be questions at all."
    - Neil deGrasse Tyson, answering loaded question in ten words or less
    at a 2010 talk MCed by Stephen Colbert.

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    Quote Originally Posted by Strange View Post
    You are right. I probably rather overstated the case. (I was going to write something much longer but it was getting late).

    I was intending to contrast "consistent with" and a word like "confirms" (for example). If someone said that something (e.g. methane) "confirmed" the existence of life then they would be effectively ruling out other explanations (and, one would hope, relying on a lot of other evidence beside that). Saying that it is "consistent with" life says nothing about other possible explanations; it doesn't rule them out and doesn't guarantee there are others. But it certainly allows others.

    I don't see why someone discussing one possibility has to, every time, list every other possibility as well. Especially in an informal context and especially when they are using cautious language such as "consistent with", "may" and "possible". I was just (over?) reacting to the way such statements are often met with "prove it" or "what about X as a possibility". I agree such a response is appropriate if someone were to say "there is life on planet xxx" but not just because they are discussing possibilities.
    Try replacing the term "consistent with" with the synonomous terms "agrees with" or "is supporting of" and you will probably more easily see why there is some "bristling" among those who require compelling evidences before they engage their "belief" engines.

    http://dictionary.reference.com/browse/consistent

    http://www.thefreedictionary.com/consistent

    http://www.merriam-webster.com/dictionary/consistent

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    Quote Originally Posted by Trakar View Post
    Try replacing the term "consistent with" with the synonomous terms "agrees with" or "is supporting of" and you will probably more easily see why there is some "bristling" among those who require compelling evidences before they engage their "belief" engines.
    OK. I accept that different people will use words and interpret them differently (from me and from each other). And that this could cause problems.

    (I am slightly surprised that, in a scientific discussion, anyone would use it to mean anything but "not contradictory". In other words, that anyone would use it differently from me. But, hey ho.)

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    Quote Originally Posted by Trakar View Post
    Try replacing the term "consistent with" with the synonomous terms "agrees with" or "is supporting of" and you will probably more easily see why there is some "bristling" among those who require compelling evidences before they engage their "belief" engines.
    The core meaning is clear. When used in a scientific discussion, especially a speculative one, it is understood to mean "does not disagree with" rather than actively agrees. I don't think there's any excuse for "bristling".

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    Quote Originally Posted by Trakar View Post
    Try replacing the term "consistent with" with the synonomous terms "agrees with" or "is supporting of" and you will probably more easily see why there is some "bristling" among those who require compelling evidences before they engage their "belief" engines.
    The issue is that the same evidence can be explained by different theories. So it is conceivable that some observations can be consistent with, agree with or be supporting of different theoretical explanations. Replacing "consistent with" with these synonyms doesn't make any appreciable difference, as far as I can see. I think what you have a problem with is the underdetermination of theory by evidence.

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