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Why does life exist and

  1. Mar 23, 2009 #1
    why does it fight so hard to continue it's existence? I'm generalizing all life as a force of it's own. It's one thing to say that life simply evolves, but in a universe of gases, rocks, and lots of space, how does the phenomena of "life" fit in to the physics of everything? What is the driving mechanism?
  2. jcsd
  3. Mar 23, 2009 #2


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    Those are separate and unrelated questions. The answer to the first really is evolution, perhaps with the anthropic principle thrown in for good measure.

    For the second and third, I don't know that there really is an answer besides to say that what we now know about biochemistry implies that life is an inevitable result of biochemistry.
  4. Mar 23, 2009 #3
    If life did not exist, then entropy would increase at a slower rate. Doesn't entropy increase maximally, subject only to constraints? Mammals our size eat food, all either directly or indirectly from photosynthesis, and dissipate the stored energy at about a 100 watt rate. Population increase certainly adds to the total dissipation rate. Man has learned by manipulating the environment (e.g., burning fossil fuels, uranium) to dissipate energy at a rate of about 10,000 watts per capita, roughly 100 times our metabolic rate. Without our superior intelligence, entropy would increase a lot slower.
  5. Mar 24, 2009 #4
    Evolution on it's own doesn't answer the question really. Evolution is a theoretically sound observation that simply explains species. The question is, what drives it? I looked up anthropic principle and it basically asks the question and gives a number of reasons. None of which are debatable or observable. Maybe it can never be understood? To me, it is very interesting that something so basic is so profoundly unexplicable, scientifically. It's obvious but there is no explanation.
  6. Mar 24, 2009 #5
    One can explain the origins of life with a process like evolution.
    You can get into all kinds of talk about crystals forming and self-replicating molecules leading to the more complex forms we call life...

    The real question you are asking is 'why does anything exist'.
    What makes the universe happen?

    And there are all kinds of explanations for that. Science doesn't deal with that very much because we only have one universe to observe, we didn't see it begin, and its hard to concieve of what got the ball rolling when you're talking about 'everything'... that is, you run into an infinite regression, which might simply be due to a lack of understanding of what 'causation' is.
  7. Mar 24, 2009 #6
    I'm not asking what makes the universe happen, that question is too abstract. I'm asking, why does life strive to exist? There is nothing we have identified that explains this. But, the fact that this process is happening, shows that it is immediately observable. It's a fascinating question to me. This explains the existence of "religion". It at least gives an explanation that cannot be disproved anymore than my question can be answered scientifically. Religions are considered superstition and illogical nonsense by a majority of the scientific community but it's interesting to me that there are fundamental things that systematic observations alone cannot identify. And we are experiencing them every moment.
  8. Mar 24, 2009 #7
    And how is that less abstract?

    Does a rock strive to exist? Why does life need to strive, when a rock doesn't?
    Life is a physical process, just like a volcano.
    Does a volcano strive to erupt?

    "life" is an abstraction, and attributing intention to it is anthropomorphism. More abstraction.
    Two hundred years ago we hadn't identified bacteria. So what? The universe is complicated and we've just started investigating it. They haven't explained who killed Kennedy to me either, but I don't blame the Pope.... mostly.
    Because the explanations religion gives are vague and often nonsensical. Its easier to make up an explanation than to come to one scientifically.
    What holds the earth up? Its turtles all the way down. Nice explanation, not that useful.
  9. Mar 24, 2009 #8
    I use the definition of life as a self-similar replicating system. It seems to apply better than most. Why life exists isn't difficult question. But when you say 'so hard' this is making a comparison ---but to what?

    There is life because life self-similarly replicates. It continues to exist when it successfully replicates. It's nearly a tautology.

    Where the plethora of mechanisms fail in replication for a particular branch, there is no life. But you are asking, not about all life, but that which has survived, I think. If so, it's not really a fair question without include life that failed in replication--which is the bulk of it. It hasn't tried 'hard enough'.
    Last edited: Mar 24, 2009
  10. Mar 24, 2009 #9
    So far I've been getting a lot of dismissal of my question. And I'm speaking of all life in general, from single cell to the largest mammals. It is relentless in it's ability to survive and compete in all environments on Earth. I don't think it is abstract at all. It's happening through a biological means that we can observe. There is a mechanism common in all life forms that competes to maintain it's existence. This is a unique quality when looking at all the processes in the universe.

    Life is not comparable to a rock. Science and philosophy are not about dismissing questions because we don't have the answer, yet.
  11. Mar 24, 2009 #10
    You're right, that's the job of religion.
  12. Mar 24, 2009 #11

    We are the eyes of the universe. Maybe the universe wants to know itself(the fields want to know why they exist). You shouldn't assume that stupid human beings can know all the answers to all questions about anything in the universe. It'd be arrogant to think so. But maybe in time i'll be proven wrong.

    My personal take on this is that neither life nor the laws of physics that allow its emergence and existence for billions of years are random events. In fact i don't believe there is randomness at any level anywhere. QM may say otherwise, but "the ol' one doesn't play dice".
  13. Mar 24, 2009 #12

    I agree but we have no idea why it's(setup to be) inevitable in the first place.
  14. Mar 24, 2009 #13
    If you want the 'deep' answer to your question, then you'll have to wait a while. :smile:

    If you're not looking for the deep answer, but instead are "generalizing all life as a force of its own" (ie., as some emergent, scale-dependent phenomenon), then you're not looking for how what we call life fits "in to the physics of everything?", because, in the big picture, the fundamental mechanism(s) that drive life would, necessarily, be the fundamental mechanisms that drive ... everything.

    So, take your pick:
    The deep question is an open one.
    The life-specific question is an open one.

    That is, there isn't, afaik anyway, a definitive answer to either question.
  15. Mar 24, 2009 #14
    LOL, you're on my line of thought. This is the natural conclusion I've considered. A kind of evolution of the Universe. I certainly believe that life obeys the laws of physics completely. It's just a level of physics we haven't grasped yet. Everything behaves exactly as it is supposed to. And this in no way conflicts with my personal religious beliefs.
  16. Mar 24, 2009 #15


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    You're looking at it from the wrong end.

    Think about its origins. "Life" at its origins was really just a bunch of simple lipids that could contain an environment and keep certain nutrients from drifting away. (Or substitute your favourite genesis hypothesis). It wasn't even alive at this point, it was just some self-sustaining and replicating processes.

    There would have been umpteen billion different configurations in the primordial soup, all with slightly different ways of competing for nutrients and hanging on to what they're got - some doing well, some not so well. Those that had superior techniques and/or properties for "striving to exist" did so. Those that did not "strive" as hard still lived, but got weeded out eventually.

    All we see, 3.5 billion years later, is the progeny of the forms of life that "strove" better than others.

    (All that being said, you can't anthropomorphize "life". "Life" doesn't do any "striving". But individual organisms do. Life is the sum total of individual behavior.)
  17. Mar 24, 2009 #16
    Help me out, you just contradicted yourself. Life strives or life does not strive? Life doesn't do anything? I haven't observed this. Can you give an example?
  18. Mar 24, 2009 #17


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    Well, what I really did was contradict the OP. It is the OP's contention that "life strives to live". This is not my contention, but I was going with it, to frame my answer in the OP's terms.

    As for my contention (and other scientists), no, "Life" does not "do" anything. Organisms do things. To hint that Life does something is to anthropomorphize it as a thing, i.e. with desires and goals.
  19. Mar 25, 2009 #18


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    The way I see it is that life came about because of a system with excessive energy that could not be equaled out in any other way then to organize into complex structures to try to dissipate this extra energy.
    So basically life is just a way of trying to even this out. When and if the universe ends it has to all come out equal to Zero. But that is just my point of view.
  20. Mar 25, 2009 #19
    why should life exist --may I attempt to re frame this question as "whats goal of life"
    Life exists because it wants to know it's purpose/goal.Life is incessantly driven by this natural force to know it's purpose.Behind it's highs and lows, the life has this one driving factor.The moment it knows it's goal, it will cease to exist as it is no longer hanuted by the quest about it's existence.

    Lets say how long would any science exist? Until it reaches it's unit cell/the one thing out of which it is evolved. When physics finds out it's unit element, out of which it sprang, then physics stops. There is nothing to be explored further. So is Chemistry, when it finds the one element out of which all the chemical elements sprang, it will cease to exist. So, all the phenomenon and nature are necesary conditions for any science to exist..Why should it be different for life?

    Lets see how metaphyscis attempts to explain the life existence.
    Science generalizes things and shows one common roof for all related phenomenon. Ex: One apple fell at a place.Another apple fell at a different place, So all apples fall down, infact all objects! So Newton explored it and observed that all objects fall down and thus came up with Gravity.This Gravity would exist even if Newton did not
    observe it and even if all human race forgets it. It is a principle ever existing

    So is life made up of principles, like whatever takes birth,(is composed of elements) will grow-->Decompose-->Perish
    This is universal, applicable to all beings which have life.
  21. Mar 25, 2009 #20
    Define striff. Define Life. I think it can be put into consistent equations.
  22. Mar 25, 2009 #21


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    :uhh: Organisms do not have "excessive" energy. They've fought long and hard to get and keep their shreds of energy, and they're not about to give them up without a fight. Organisms operate on a tight energy budget, which is why you don't see a whole lot of large-brained, large-bodied animals with fifty legs running around at top speed. If an animal is exceptional at one thing, then it has done so at the great expense of many other things.
  23. Mar 25, 2009 #22
    In my opinion, the driving mechanism is evolution, which is a direct consequence of physics. Physics produced the environment, like the earth and a nearby sun; this can be viewed as a process of evolution, though it is obviously not biological. This environment was conducive to the successful evolution of organic molecules into the first and simplest forms of life by the physics of chemical cues. Eventually, evolution produced sentient organisms that could respond to their environment.

    I agree with Dave's previous response. It is not Life that strives to continue its existence, but organisms. Every organism is egocentric in their perspective of reality and the top priority is survival. There are many ways of increasing the probability of survival, such as evolution and forming organizational hierarchies, which need not rely on a general life force as you suggest.
  24. Mar 25, 2009 #23
    Life (I really mean organisms) exists because the physics of our universe provided the means to do so and non-existence is a very unattractive option. We strive to survive and that is the main goal. Only when this condition is satisfied, life can then contemplate its purpose.
  25. Mar 27, 2009 #24
    It hardly matters. All the multicelled organisms are dead-ends, anyway. They are way too specialized and fragile to make it through the changes that bacteria manage. They don't learn from the last batch of dead-end attempts; there's no genetic code to tell a bacterium it's a loosing game to go multicellular.
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