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Journal insanecarbonbasedlif's Journal: What is life? 16

Journal by insanecarbonbasedlif

I've run into flack for the broadness of my personal definitions of life, that is, what is alive, what are the properties of life, and all that. What do you all think a good definition is, and are you concerned with the broadness of it applying to, for example, electro-mechanical constructs?

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What is life? More

What is life?

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  • ...is information that replicates and perpetuates somewhat independently of context, and, arguably, has some teleological purpose about it.
    A friend once tried to contend that a Pentium chip was alive, and simply using Intel engineers to aid its nativity, and I accused him of mental gymnastics. The argument, while novel, dies on the vine if the engineers walk away.

    • Well, that's a workable definition. The inclusion of teleology as a prerequisite is not worthwhile, I think. Arguments can be made as to why people would have faith that there is some teleology to life processes, but I don't think there's any consideration given to teleology when trying to decide whether a prion is alive or not, or whether an electro-mechanical system is alive.

      Which, following up with your friend's creative Pentium argument, brings me to my next question. If a machine was made that

      • Yeah, the teleology point might be my own bias leaking through. Caught putting in a plug for my sponsor again.
        With regard to your second point, I would point to my "somewhat independently of context" point. Is the machine operating from fixed ROM, where any alteration outside of its error-handling code stops its process?
        DNA-based replication is significantly more sophisticated than any Rube Goldberg-ish machine, or even a machine shop turning out machine tools.
        So, maybe there is a complexity metric tha

        • The machine has some unknown mix of RAM and ROM. For a best case scenario, I would say it's using fuzzy logic for both production and stimulus response, and has a certain error (mutation) rate in copying of both software and hardware. Obviously, the error rate would have to be within a reasonable range, or the species would be very short lived, but that's not a hard parameter to nail down.

          • One can speak of internal error rate as well as sensitivity to external noise inputs.
            Something not alive is going to fare poorly in dealing with either.
            Of course, naked human beings don't do so well in space. ;)

            • Living things (that is, things that people unequivocally agree are living) are in some cases extremely tolerant of internal error and external change, and in other cases, hyper-sensitive. Naked humans in space being one example, but some people's reaction to allergens (peanuts, bees) is a more common one. So, while I think that's a fairly general criterion.

  • A definition that works quite well... It consists of five or so points in the style of "must replicate", "must have a metabolism", etc.... Lemme see if I find a link: Of course... Wikipedia [wikipedia.org]

    That's what we learnt in school, but there probably are some counterexamples. I'll go and read it now.

    • I don't think this counts as a counterexample, but I think that list is broad enough to encompass human-created electro-mechanical life, or even completely electrical life (that is, life inside a computer). Is a definition that broad agreeable to you?

      • Depends if the conditions have to be merged with an and or with an or ;-) Take fire for example. We do not consider it alive but it does satisfy a number of those points.

        Now, a metabolism for example, I have a hard time to picture with electrical life (we're talking "life", not "intelligence", I must presume). Of course, I'm sure you can come up with something, but then you must admit that "The Sims" are for all intents and purposes "alive". Are they?

        • I think if you reword "Metabolism" to be converting energy into structure (i.e. chemical engery into cell walls, or electrical energy into logical structures), it works just as well, and doesn't run into the anthrocentric problem as much. I don't know enough about "The Sims" in particular to know if they count as life forms in an logic based electrical world, but I happen to use such a broad definition of the idea of life* that I actually consider many things that are generally called "simulations" to be ru

          • I consider anything that adapts to its environment, grows, and produces offspring to be life

            In that case "The Sims" are life, even though it's the player that makes them adapt... Even then, left on their own, they will do stuff (eat, be lazy, etc...) They can also produce offspring, but I don't know if they can do it on their own. (Meaning: without player inter-action.... However they could most certainly be programmed that way if Maxis would want to.)

            Anyway, with your definition "fire" can be seen as ali

            • Ergo, by your definition "fire" is life.

              Well, considering that everything that is unequivocally considered life is actually composed of lots of atoms and molecules undergoing chemical reactions all the time, I think an argument can be made that fire is a form of spontaneously arising, rapidly growing, and extremely transient life. Consider rust, an extremely slow form of oxidization - at first glance, it looks like, and grows (yeah, people use the word grows for fire and rust; this is very telling, I think) like molds or lichen. And, yes, I am aw

              • In that case, haven't you found your definition of life and as such the journal discussion is closed?

                Let me conclude with the idea that life is just a special form of chemistry....CDK007 on abiogenesis [youtube.com]. I agree with him.... (And never really disagreed with you, I just tried to provoke thought)

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