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I need a logical justification for this question?

  1. Nov 20, 2005 #1
    I need a logical justification for this question???

    Why does a living thing have to perform these 8 functions ( respiration, regulation, reproduction, growth, excretion, nutrition, transport, and synthesis) in order to be considered living? Why aren’t all things considered living?

    Basically does this make sense:
    LOGIC PROOF 1: All living things are made up of cells. All cells are made up of atoms. Thus all living things are made up of atoms.

    LOGIC PROOF 2 (in conjunction with LOGIC PROOF 1): All things in the Universe are made up of atoms. If all things living are made of atoms and all things in the Universe are made atoms, then all things in the Universe are living.
     
  2. jcsd
  3. Nov 20, 2005 #2
    They have to, to be alive on Earth. However it is possible that life on other planets may devolp in other ways. Micheal Crieteon explored that concept in his book Andromena Strain. Did you read it or is this just a manifastation of your own thoughts?
    -Scott
     
  4. Nov 20, 2005 #3
    This is just a manifestation of my own thoughts.

    so umm does anybody have any reasons to disagree with my logic proof or any thoughts on this topic.
     
  5. Nov 21, 2005 #4
    Ask yourself this, given a lot of atoms (enough to make up an organism), how many possible ways can these atoms interact with themselves. The possiblities are very large (some may argue infinite.) Now imagine observing that a very small of number of the possible interactions are observed more often then seems probable. By this I mean that the interactions of atoms in a living organism by chance alone seem very unlikey. So we call this specific arrangement of atoms life. Now the reason we observe a certain way is a consequence of our senses and perceptions.

    Here's this as well...

    if A then B doesn't imply if B then A.

    If a dog is black doesn't imply a black is a dog or all things black are dogs.
    If smart people are tall it doesn't imply that all tall people are smart.
    If all living things are made of atoms doesn't imply that all atoms are living.
     
  6. Nov 21, 2005 #5
    true i do like your logic but i could also just easily say
    If A implies B then B implies A such as:
    If all things living have atoms all atoms are things living.
     
  7. Nov 21, 2005 #6
    a good question would be if a machine could think would it be alive implying it would be life.
     
  8. Nov 21, 2005 #7
    Absolutely not. All cells are made up of atoms, but not all things that are composed of atoms are necessarily cells.


    It is worth noting, however, that viruses and possible prions challenge conventional definitions of what it means to be living.
     
  9. Nov 21, 2005 #8
    well i didn't say that all atoms are cells what i did is that all cells are definately atoms but atoms are the building blocks of cells not the otherway around. If the logic proof says that cells are the building blocks of atoms plz tell me where it shows that. All i'm saying is that the current definition of living is wrong because it doesn't provide a reason as to why cells are defined as living but not atoms. If atoms are what make cells up i don't see a reason as to why we wouldn't define all things as living.
     
  10. Nov 22, 2005 #9
    While it is true that a cell consists of atoms, there are many things that are not cells that are also made up of atoms. Thus, something that is made up of atoms is not necessarily an cell.


    Allow me to use an analogy that might be easier for you to understand. All cars are made out of metal. Does this mean that all things that are made out of metal are cars? No, it does not. Now substitute "cars" with "cells" and "metal" with "atoms" and you may be closer to understanding why all things are not living.


    Again, I urge you to please take a jr. high science class on biology and chemistry before you continue to claim to know more than the entire scientific community about what defines life.

    Thanks,
    bluenotem3
     
  11. Nov 22, 2005 #10
    your extremely funny bluenote but i never said that all things that are made out of atoms are cells. that is an assertion that u put in to my mouth so u are not actually correcting me to any extent. now if someone could actually address the question at hand that would be nice.
     
  12. Nov 22, 2005 #11

    Moonbear

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    All you seem to be trying to do is redefine "living." The definition of living is NOT that something is made of atoms, it is that it meets those 8 criteria you listed in your first post.

    Your "proof" is not logical. Living things are a subset of things made up of atoms (as in your first statement). However, that does not mean all things in the superset (all things made up of atoms), belong to the subset.
     
  13. Nov 22, 2005 #12

    Evo

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    No, it does not make sense. You're forgetting that all non-living things are also made of atoms.
     
    Last edited: Nov 22, 2005
  14. Dec 9, 2005 #13
    JESUS CHRIST LOOK! the definition of living is anything which performs those 8 functions. A cell does this and just so happens to be made up of atoms. Now the problem here is that cells came from somewhere, they just didn't exist like atoms and energy have. they are not infinite, like matter and energy. For instance when the big bang happened, cells didn't go flying out into the universe, matter and energy did. So heres where the flaw is. According to this definition of living it doesn't explain where the first cell came from. it also implies that all cells must come from preexisting ones (living can only produce living).
    This doesn't make sense because of what I just said above, that cells did not just exist. They are created from the systematic structuring of atoms. So this is what i'm saying how can atoms which are defined as dead, inanimate, or not living, give birth, produce, or create cells which are defined as living. This means that the dead or not living can give birth to the living. DOES THAT MAKE ANY SENSE. NO IT DOESN'T. Thats why i am changing the definition of living to include atoms and energy because they are what created cells. this proves that cells shouldn't be defined as the basic buidling blocks of living things because having this premise means that cells (living) got created by atoms (dead). How can something dead give birth to something living. It doesn't make sense. Only living can give birth to living which proves that atoms and energy should be defined as living. DO U SEE NOW
     
    Last edited: Dec 9, 2005
  15. Dec 9, 2005 #14

    somasimple

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    Hi,

    Stars grow and die and made of atoms.
    But are they living ? Just no.
     
  16. Dec 9, 2005 #15
    see u even show the falacy just by your comment. how can a star live and die if its defined as not living. how can something thats already dead live and die. ITS SO STUPID
     
  17. Dec 9, 2005 #16
    You have a ligitimate arguement. However science's current defination of living is the way it is for a reason. Chemical reactions occur all the time in nature. It just so happens that a series of very complicated reactions inside actively dynamic objects denote life. Life may have organized itself from a series of very basic reactions occuring in a mixture of atoms, however this mixture is not changing and dynamic as a cell is. A rock responds to the enviorment with certain inputs but not in the same complex way a 'living' organizm may respond. There is a difference between a high level of organization in a complicated molocuel and a living thing. Living things are cyrstals so complicated the human mind can barely farothum all of the reactions and changes occuring in a single instant. A rock per say will not change. It will not look for food, it will not move on its own, etc. It does however organize itself chemically to have the most stable state. This is the basis of all reactions and of life itself. Once more your arguement makes sense, but the current defination of life is withstanding because of the constant change and complexity involved in these molocuels known as cells.
    Hopefully this provides some insight,
    -Scott
     
  18. Dec 9, 2005 #17

    somasimple

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    Hi,

    Nobody is able to convince him. his logic is wrong from the start.
     
  19. Dec 9, 2005 #18

    Monique

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    LOGIC PROOF 1: Lemons are made up of cells. All cells are made up of atoms. Thus all lemons are made up of atoms.
    LOGIC PROOF 2 (in conjunction with LOGIC PROOF 1): All things in the Universe are made up of atoms. All lemons are made of atoms and all things in the Universe are made atoms, then all things in the Universe are lemons!

    no?
     
  20. Dec 9, 2005 #19

    DaveC426913

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    This is the crux of GE's confusion. Help her to figure out how life came from non-life and her whole illogical argument goes away.
     
  21. Dec 9, 2005 #20

    Monique

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    Many things didn't go flying out into the universe during the big bang, there was an 'evolutionary process' where small consituents came together to form larger and heavier atoms. Then the atoms came together and formed molecules, molecules came together to form more complex structures that eventually led to a chemical system that we call life. Life is not absolute, that's why the definitions are needed to know what to include and what not.. as said there is still a lot of discussion whether virusses should be considered alive or not.
     
  22. Dec 9, 2005 #21

    Moonbear

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    That's simply arguing semantics. The "death" of a star is a different meaning of the word "death," than the "death" of a previously living organism.

    The problem you seem to be having is that you want the precursor of life to be defined as alive too, except those same precursors didn't only come together in the direction that became life, but also came together in other ways to form non-living things. You also have it backward. The definition of life isn't that it came from other life, but that one of the properties it holds is that it is capable of reproducing. However, if something can reproduce and make new life, it is not necessarily life itself. No single property is sufficient in the definition, they must all be satisfied.
     
  23. Dec 9, 2005 #22

    somasimple

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    Hi all,

    I used the words "death" and "life" intentionaly in place of duration. We use half life for radioactivity in the same way because man trends to give "life" to non living things.

    Where is the frontier in a cell? Where is life set in a cell? God Entity trapped us with his question because there is no response to give actually.
     
  24. Dec 9, 2005 #23

    DocToxyn

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    The definition of life does not need to explain where a cell came from, it simply defines what it is to be alive, not to assume life. Plus it makes no implication as to the origin of life, it only constructs the parameters that we use to differentiate between something living and something not. You're trying to make the definition explain too much.

    Maybe this will help. Before you stands all the required parts and fuel to make a car in an unassembled state. Is it a car? No, because it doesn't look like a car, it can't be started like a car, etc. Now you carefully assemble all the pieces into a functional unit, fuel it up and turn it over, it runs perfectly and you drive off. Is it now a car? Yes, it does all the things you expect from a car. Granted it is not alive, but it is clearly something entirely different from the pile of parts it once was. Thus, following the same example, the assembly of organic parts and fuels to make a cell and then an organism, proceeds from non-life to life, just as the car proceeds from non-functional to functional.

    Here's another perspective. By your definition of life (which I think we all agree with) stated in the original post, the two units that come together to form life, ie sperm and egg are not technically alive. They lack many fundamental cellular processes and/or machinery to fit into that definition, therefore your example of two "non-living" things that come together to ultimately form a living thing.
     
  25. Dec 9, 2005 #24
    It seems that everyone is trying to give Godentity their two cents. But it seems to me that he/she is simply rejecting the first assumption everyone makes with either "why does it have to be that way." Bottom line is everything is made of the same stuff. Human brain has developed naturally to be able to resolve things. By that I mean that a human that has never been taught anything by another human will go into the world and be able to resolve or tell one thing apart from another. There in lies the invention of categories and names. So when we name or categorize something, that's all we're doing. Your asking the wrong questions here. You should be asking why do humans resolve things so that one thing is separate then another thing? Then you'll realize why life is what it is...to us..humans.
     
  26. Dec 9, 2005 #25

    selfAdjoint

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    I pretty much agree, except that your statement that an untutored child will learn to categorize is optimistic. There are historical examples of children left to grow up by themselves in the wilderness, and they were pretty sad cases. It's not clear that they arose to any higher human classification powers. I conclude that human cognition is only achieved in a social setting.
     
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