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Are We a Living Thing?

  1. Jun 5, 2008 #1

    Pythagorean

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    or are we just a collection of living things (i.e. cells) working in coordination?
     
  2. jcsd
  3. Jun 5, 2008 #2
    I see life as a process, rather than an entity in itself.
     
  4. Jun 5, 2008 #3
    I think it's somewhat comparable to say a piano.
    Is there really a piano or is it a bunch of strings and wood blocks.
    I mean, we can say this about anything basically.

    I see a human as a complete life. If we go by the wikipedia definition of life, which includes reproduction, response to stimuli and so forth, we see that we need to include a lot of different things that individually would not be life.
    Therefore I think a life is a compound of different functions, like the ones mentioned on wikipedia..

    But on a more analytical level, if I cut off my arm, that arm could say to be alive at least for a period, so that brings up some interesting questions like which things define life.
    But I don't know exactly what you meant in your original post so won't get into it.
     
  5. Jun 5, 2008 #4
    I would say a living thing. All of our "parts" work together with a central mind in control. A colony of ants would be a "collection of living things working in coordination".
     
  6. Jun 5, 2008 #5

    Pythagorean

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    So in that aspect then you would say the Earth is alive? Or perhaps the universe? Noting that single living cells came together and formed animals that we also call living.

    I'm no biologist, I'm a physics student who has just been reading a lot about the cell lately as a precursor to neurology.

    As far as I know, your cells can live separately from you as a complex functioning living thing. Cells themselves have "organs" called organelles. Each of your cells also has your complete structure "on file", structures that lead specifically to your physical and mental characteristics (+ errors, but the cell somehow knows that it can generally get a six if it rolls six times, which is why it sees the advantage in symbiotic relationships with other cells).

    Perhaps when we perceive consciousness we are undergoing long-term orders from the cells who have been practicing their code-writing for billions of years, passing the code down through cell generations.
     
    Last edited: Jun 5, 2008
  7. Jun 5, 2008 #6

    Pythagorean

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    I'd have to disagree about it being like a piano. Pianos have no fractal nature to them whatsoever. Life does. Living cells are also defined as living, just like you and me. Piano strings are not defined as pianos.
     
  8. Jun 5, 2008 #7
    Debating the merit of an analogy may not be so fruitful but of course neither is philosophy so here I go: like living humans, cells are defined as living, but not as human. Like inert objects, piano strings are defined as inert but not as pianos. The analogy works.

    The fractal parallel however does not work for more than a single step. While humans are made up of components (cells) that are considered alive as well, this doesn't hold for the cells themselves: their components are not considered alive.

    So what is life? I like Moridin's interpretation. Life is a process. An entity that undergoes this process is called alive. This works for individual cells as well as a whole human. Yet another analogy would be that of a machine made up of other machines, like an automobile. The whole is a machine, and so are a number of its parts. At some point parts are no longer considered machines, they are just parts.
     
  9. Jun 5, 2008 #8

    Pythagorean

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    to the contrary, I remember hearing lots of theories about the animal cell today being made up organelles that may have actually been their own single-celled organism at one point and formed a symbiotic relationship with what is now the animal cell.

    I'm not sure that flies with me very well. A better analogy exposing the fractal nature of pianos would have been to talk about how a piano has notes, but so does a single string. Furthermore, each string's note has more notes (the harmonic series). So yes, I take it back, this is a pretty decent analogy. But we do call all those things 'notes'. I wouldn't be claiming that a note is a piano. I'm claiming that the piano is NOT a note. That would make the analogy consistent.

    If you'd like to carry the analogy to the animal being the string, well then the string's only a single note in the reference frame of the piano (not the guitar, for instance). In this way, it's not really a single note (adding that the harmonics series of note anyway). Only a pompous pianist would presume such profuse propaganda.
     
    Last edited: Jun 5, 2008
  10. Jun 5, 2008 #9
    No, I think that's enough analogyzing. Staying with your OP where you ask if we are a living thing or a collection working in coordination, under the point of view that life is a process then both points of view are not mutually exclusive. Each cell undergoes a process we call life. The collection of cells that form a human also undergoes a process we call life. We are both a living thing AND a collection of living things. One does not preclude the other.
     
  11. Jun 5, 2008 #10
    A well-rounded operational definition of life could be "a self-sustaining chemical system that can undergo Darwinian evolution".
     
  12. Jun 5, 2008 #11
    Basically, we are part of a system. Just as we are a system with components in it.
     
  13. Jun 5, 2008 #12

    Pythagorean

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    I guess I'm trying to find the difference between obvious biological systems and systems like our planet. I doubt evolutionary processes apply to Earth at all though. It can be said that it has changed with time, but as far as we can tell, it does this in accordance with the physical laws that govern it. But how are life systems different (given that the chemical system is fundamentally a physical system) than other cycles that exchange energy and chemistry. For example, would it be possible for non-biological systems to experience consciousness? Could we even answer such a question?
     
  14. Jun 5, 2008 #13

    Pythagorean

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    Yeah, I didn't mean to imply they're mutually exclusive, my apologies. My OP is meant to assume that cells are living either way.
     
  15. Jun 7, 2008 #14
    Hence my piano example.

    Humans may not be a living thing as a whole, that may be a thing we apply to ourselves by means of our brain, just like the piano is not really a piano, it's a collection of it's component parts.
    But either way it gets kind of messy in my head when I think about this.
    Like for instance how do we define what a living things boundaries go?
    We know that the body is contained within the skin, so is the skin the boundary of the living entity?
    Can the skin be defined as the life, and everything within it is alive?
    Because in that case we just have to say that everything contained within a container of sorts that belongs to the entity, is as a whole a living thing.
    I don't know if you want to get this overly complicated about it though.
     
  16. Jun 7, 2008 #15
    1) That's because the earth is not alive?
    2) If consciousness is seen as also a biological process or metaprocesses nested within other biological processes, then the sort of consciusness we experience would be improbable given non-biological processes.
     
  17. Jun 7, 2008 #16
    Does 'we' include frogs, bacteria, worms, plants etc too?
     
  18. Jun 7, 2008 #17

    Pythagorean

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    My point is that consciousness doesn't necissarily belong to life. Cells themselves are pretty automated. I'm suggesting that "Consciousness" could be the result of living things working together in a very complicated, but ordered process.

    The reference I'm about to cite views societies of prokaryotes as a multicellular organism. It's not widely accepted; it might even be a source of debate.

    Shapiro, J. A. 1998. “Thinking about bacterial populations as multicellular organisms.” Annu. Rev. Microbiol. 52: 81-104.

    But as I get deeper into studying biology, I'm starting to find that the definition of life simply revolves around DNA. Is that the case? Is there anything we consider living that doesn't have DNA?

    I haven't seen anyone use DNA in their definition of life.

    not bacteria, they are single-celled, I believe, so they're assumed alive for sure in this discussion. The others are multi-cellular, so the question would be about them too. Though I'm starting to see that all these things have DNA specific to them (the DNA in a frog is probably a lot different than the DNA of a single-celled organism from the past that evolved into a frog)
     
    Last edited: Jun 7, 2008
  19. Jun 7, 2008 #18

    Pythagorean

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    These are similar to the questions I've been asking myself about this. I wonder why DNA is never included in these definitions though. It seems to be the clear difference between self-organized systems that we consider alive and those that we do not.
     
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