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Is there intelligent life out there? I have a strong argument that says no.

  1. Sep 15, 2011 #1
    ...or maybe not a definate "no", but a positive "much more rare than scientists predict".
    I have been pondering this question, and every scientist I hear speak on the matter does the famous "alien life equation".

    What they fail to do is factor in a few variables along with how many planets have water and are in the "goldilocks zone"

    1. When viewed from earth, we have one moon and one sun that are the exact same size.
    This ratio of matter and gravity broke and continues to break up our supercontinent when it forms.
    The moon effects our tides just enough not to be destructive, but it helps oxygenate and mineralize our waters, along with our sun. And since its theorized that we all originated from the water, a planet having a moon and sun close enough to churn our waters is important.

    2. We have a gas giant close enough to us that it "helps" deflect some space junk, keeping major asteroid calamities at a minimum (IMO)

    3. We DID have had a calamity with an asteroid that was big enough to melt the majority of the iron in the earth, and sank it into the middle which helped give us a sizeable magnetosphere. Which protects us from gamma rays, solar winds, etc etc.

    4. Our "smarts" did not make a major jump during the evolutionary road until we had plenty of meat, and a very balanced diet. Which says to me, intelligent life needs a LONG LONG LONG time to develop. So you need pretty much a stable planet because you can only get so far when you have to start all over every 100 years.

    5. The sun and moon also keep our earth "warm and toasty" on the inside, and plate tectonics are more important for life than we ever knew in the past.
    It is important to our weather and our coastlines.

    6. This also causes Vulcanism which is also important for our soil, food, land, and of course yea old plate tectonics.

    7. I could go on and on...but I will stop here and finish with one last thought.
    There are many people living who remember a time before we even knew how to split an atom.
    If you look at every single living creature and their will to survive, violence is in our nature if we want to admit it or not.
    Us (as human beings) are the "creme' de le creme'" of intellegent beings as far as we know...and we can not even resolve our problems without war.
    If intelligent life ever did exist on another planet... does intelligence have a very long lifespan?
    All arrows tend to point to "no" if you ask me.

    So you basically get where I am going with this argument.
    When you factor in all these variables, are we just lucky?
    ...or do you think there is life out there.
    I happen to think it is more rare than anyone ever expected it to be. Do the equation with all the variables figured in.

    I do not post alot in forums, this topic has just been on my mind so much, I would like to hear others points of view on the topic.
  2. jcsd
  3. Sep 15, 2011 #2
    Could you specify which equation? I assume you mean the Drake Equation, but clarifying that would be beneficial.
  4. Sep 15, 2011 #3


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    I assume the http://en.wikipedia.org/wiki/Drake_equation#The_equation" as well.

    It does take into account the lifetime of an intelligent civilization (7th variable: L).

    The size of Earth's Moon is certainly a factor considered in almost any conscientious guesstimate of alien life. It is covered in the 3rd variable ne.

    Note: Scientists do not predict how likely intelligent life is out there. The Drake equation is an equation that identifies generally what factors are involved. It leaves it up to the reader to insert their own numbers.

    Fine, so the numbers you'd insert into the equation might be a little lower than others.
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  5. Sep 16, 2011 #4


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    As has been pointed out the drake equation predicts nothing. Rather it identifies a possible way you could potentially identify how many "intelligent" species are likely to exist if you know the answers to the variables.

    This is a huge fallacy because goldilocks zones refer to conditions under which Earthlike life can evolve. It doesn't say anything about the likelihood or implications of http://en.wikipedia.org/wiki/Hypothetical_types_of_biochemistry" [Broken].

    Do you have any references for any of this? These are also disjointed points. The Moon and the Sun are not the "exact same size" (that's something I have heard creationists claim a lot). Hence why we get different eclipses.

    Certainly Jupiter is credited with grabbing up junk but I'm unaware of how different it would be without it.

    What evidence is there that this is the only way that the conditions for a magnetosphere can be generated? Futhermore in periods of geomagnetic reversal the magnetosphere weakens greatly yet there is http://scholar.google.com/scholar?q...eversals&hl=en&as_sdt=0&as_vis=1&oi=scholart" of a link to any kind of extinction event. I remain unconvinced that life could not arise on a planet without a magnetosphere.

    This is not true. There is no compelling reason why a species with our intelligence could not have evolved at almost any point since the Cambrian. The reasons as to why we evolved intelligence are not clear however current understanding is that it was selected for thanks to the increased success of group behaviour; Theory of mind applied to prey, applied to fellow animal, (selected for), applied to self and voila.

    How does the Moon contribute to the energy entering the Earth in a manner that would make evolution of intelligent life impossible without it? And how exactly are plate tectonics important for the evolution of intelligent life?

    Again why is this necessary for intelligent life? Vulcanism is not the primary method by which soil is nourished. Rain helps massively in this arena.

    Nonsense. Violence doesn't prevail in human societies, cooperation does. This is how we arose to the state that we are, not violence.

    We cannot meaningfully predict how many tool-using intelligent species occur in the universe because we do not know the factors that cause this nor the conditions in the universe.
    Last edited by a moderator: May 5, 2017
  6. Sep 16, 2011 #5
    1. As has been pointed out, the sun and moon aren't the same size, they just appear that way to us. At some point in the future, the moon will (IIRC) will appear smaller than it does today. AFAIK, the concensus is that internal heating of the earth (which is mostly caused by radioactive decay of promordial radionuclides) causes plate tectonics. What oxygenates the seas better is wave action, which is primarily caused by winds, not tides.

    5. Weather is caused by the uneven heating of portions of the planet and the resulting movement of air masses. Any planet will have this (assuming they have air masses in the first place).

    6. Again, vulcanism is ultimately a result of primordial radionuclides in the earth.

    7. Violence may be part of our nature but it isn't the dominant part. Many species have cooperative societies just like us. There's nothing to say that a species with a "hive mind" couldn't develop intelligence on par or greater than humans.
  7. Sep 16, 2011 #6


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    Mr. 360,

    Despite the details of your argument (which others have picked at), there's nothing fundamentally wrong with your observations: intelligent life may be extremely unlikely. However, for all of the "divide by tens" the probability of of intelligent life might suffer, the fact still remains that it arose on 100% of the planets we've begun to explore in depth.

    I fully agree, that it seems that none of the other planets in our own solar system now (or indeed have ever) supported intelligent life (microbial life or simple plant/animal life is yet to be seen). But perhaps "thinking meat" is the least likely form of intelligent life in the universe. Perhaps we are the rarity searching for other rarities; diamonds searching for diamonds instead of sand searching for sand.

    Either way, as Carl Sagan was fond of saying, there's no shame in admitting you don't know. We all have intuition, and the only things that separate our firm understanding of fact from that vague tugging of "common sense" are the harsh mistresses of Science and Rigor.

    So, it's true to say we don't know how abundant intelligent life in the universe is, but we do know that it is possible.
    Last edited: Sep 16, 2011
  8. Sep 16, 2011 #7


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    I guess you have a conservative definition of 'in-depth'. Cuz I can think of at least two we've explored in depth.

    Um. Not none. One.
  9. Sep 16, 2011 #8


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    Maybe. I feel like we have a much better grasp on our own planet's biological history as opposed to, say, Mars'.

    Uh, yes, embarassing typo. Should read "...none of the OTHER planets[...]."
  10. Sep 16, 2011 #9


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    Hey, he said intelligent life :tongue:

    Your arguments are fair OP but I have contentions.

    Consider if there were life on a zillion different planets all springing up and evolving simultaneously with Earth.

    All of them looking for intelligent life and lacking the tools to easily discern its presence, just like us.

    Just think, there could be trillions of civilisations ALL stuck at the exact point we're at now, thinking they're all alone.

    Then a couple of them develop interstellar communications techniques and suddenly the entire cosmos just explodes into life - "Holy crap we had no idea you existed all along... and neither did the 300 other civilisations that introduced themselves to us today!"

    Could happen!

    We're like blind men feeling around inside an endless dark hallway for other critters who we think are probably blind like us when actually they might not even use senses to percieve reality the way we do.
  11. Sep 19, 2011 #10
    What is intelligent life? Maybe a better question is what isn't intelligent life. It seems to me that we are coming to the point when we realize that we aren't really that much more intelligent than many other animals. They communicate, they make and use tools, they build things. All the things that we once thought we alone did, things that made us unique, we now know aren't. I would have to say almost everything with a brain is intelligent. So if there is life there will probably be intelligent life.

    We should stop referring to intelligent life as if it were solely our domain. This planet is full of intelligent life. We are a technologic intelligence and civilization, not just intelligent life. That is what really distinguishes us.

    One other thing distinguishes us from all other animals. There are a few other animals that understand death but we are the only species that understands personal death. We are the only animal that knows that we will die. Maybe that is the thing that truly defines intelligence.
  12. Sep 19, 2011 #11


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    I agree slightly moejoe15, intelligence is a vague and multifaceted thing. It would be better to use terms like tool using or conscious. I don't think an understanding of death is what defines us, feral children don't understand death any more than animals do. Though I also don't think it is fair to suggest animals don't understand death (what animals? what understanding? etc)
  13. Sep 19, 2011 #12
    I didn't say it defines us, I am saying that it is the only thing that makes us unique. No other animal knows it is going to die or changes its actions with that knowledge in mind. We change our behavior many years in advance because of that knowledge.

    It doesn't matter what a feral child doesn't understand, what matters is what we DO understand.

    Some animals, like Elephants, understand death. I said that they don't understand personal death. Even though an animal sees and understands death it does not have the intelligence to extrapolate that it too will die eventually. We are the only species that has to live with that knowledge, thus we invented religion.
  14. Sep 19, 2011 #13


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    It doesn't matter.

    It's like a guy wandering for days in the frozen wilderness, stumbling across a farmer's house with a blazing fire on the hearth, a phone and a truck. And the frozen guy says 'Too bad. What I really need is a hospital...' :wink:
  15. Sep 19, 2011 #14


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    It is not the only thing that makes us unique. I've never seen anything but a human type on physics forums for instance. Animals change their behaviour all the time through fear of harm, I don't think you can make the definitive statement that they don't understand death.

    It matters a great deal because it separates knowledge from the capacity for knowledge.

    How do you know? You cannot make this statement definitively.
  16. Sep 19, 2011 #15


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    Guys, this is off-topic.
  17. Sep 19, 2011 #16


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    Quite. Thread closed.
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