what is "life?"

[billy rubin]

alien lifeseems to me to be a very likely occurrence

remember the drake equaton?

but when we'r elooking for civiliztions and wondering whether they're communicating, we're essentially lookign in the mirro and trying to see ourselves

what makes me curious is whether "civilization" is even a reasonable expectation. sure, we have a sample size of one, which is us, but that doesn't let us evaluate whether we're at all likely to find something that looks like we do. i keep thinking about all th eforms of highly evolved life for which our patterns of existence are totally irrelevant

https://www.youtube.com/watch?v=MOL10kuSt1s

^^this was as close as i could get to a video of a radiate organism without intrusive captioning. even here, we re trying to pigeonhole a form of life into a human system of clasification using names, sound, and a screenplay, all of which are superimpositions of human culture into a world where it doesn't exist.

what if life is recognizeable but unclassifiable?

what is"life," anyway? we're not even sure whether we should call a virus alive, or at least, i'm not.

[billy rubin]

this came to me in tank's thread about alien communication. here's someone's definition

life līf►
n.   The property or quality that distinguishes living organisms from dead organisms and inanimate matter, manifested in functions such as metabolism, growth, reproduction, and response to stimuli or adaptation to the environment originating from within the organism.

^^^this seems like a pretty good description of what i might call life around where i live.

but does something have to have all these characteristics for us to call it "alive?"

look at reproduction. the whole idea requires a final form to be agreed on. crystals grow in the right environment, but do they reproduce? is reproduction exclusive of crystal accretion?

crystals respond to their environment by incorporating different chemicals into their structure, like the difference between aragonite and calcite being the magnesium, but not much else. solife would therefore seem to require a final fixed form, else reroduction could not be established.

what if life has no final fixed form? is a slime mold an organism? an atom? a galaxy?

"response to stimuli" means behaviour. does life have to "behave?"

i dunno. if we can't recognize life unless it looks lots like us, will we be like ly to discover it?

just thinking

[No one]

- A joke.


And death is the punchline.

[billy rubin]

i don't disagree. but the joke isn't in the phenomenon, it's in the imaginary meaning we like to ascribe to it.

in my opinion, an atheist world-view is generally a life lived in intellectual denial of the facts, because no matter how much we detest injustice, dishonesty, cruelty, and pain, it's all just soo much entropy in the end.

still, i have no difficulty skipping on the surface over the indifferent depths, and i think the radiata are beautiful things.

if the universe can offer similar beauty elsewhere, i'm all for it.

[Dark Lightning]

Biologists generally maintain that viruses aren't alive-

"Viruses are not made out of cells, they can't keep themselves in a stable state, they don't grow, and they can't make their own energy. Even though they definitely replicate and adapt to their environment, viruses are more like androids than real living organisms."

[billy rubin]

what is an "android?"

i think its clear that viruses are not alive in the sense that a monkey is alive. but ^^^this definition seems more like one of those describing things rather than defining them.

for example, viruseas are certainly not cellular. but i don't see why that should be part of the definition. it's like defining life as containing chloroplasts. easy to do, but lots of things don't contain chloroplasts that fit the rest of the definition. look atthese weird things

https://en.wikipedia.org/wiki/Plasmodium_(life_cycle)

so that leaves homeostasis, growth, and respiration. if these are characteristics of life then sure, viruses are not alive. but are they definitional or just descriptions of things we intuitively already have decided to call alive?

i don't know. i'm not convinced i know what life is, in the end.

[Dark Lightning]

I don't know either. One year of high school biology was enough to turn me off to squishy things. It's why I was a mechanic instead of a doctor, which career I did consider. I don't like the sight of blood at the tender age of 68 (especially my own), and I didn't like it then. I'd've felt like shit if a patient died, as well. I don't give a shit if a vehicle dies, though. It just goes to the junk yard...excuse me, vehicle dismantler/recycler. 

[xSilverPhinx]

That's probably one of the most important questions in biology and there definitely are no easy answers.

When I was an undergrad we learnt that living organisms are creatures that:

- Have a metabolism;
- Have genetic material;
- Grow and reproduce;
- React to stimuli;
- Are made up of cells or are a cell, which is considered to be the smallest unit of life;
- Evolve.

*counts fingers*

I think that's about it. 

Of course, per this definition viruses are not alive because they do not have cells, lack a metabolism and have to hijack the cellular machinery of a living cell in order to reproduce. I wouldn't refer to them as "androids", rather "viral particles" (I'm in the camp that believes viruses are not living beings -- they're basically genetic material enveloped in a lipid and protein capsule). There are a number of biologists who argue that definition of life must be expanded to include other kinds of organisms on this planet, such as viruses. There's very likely already an updated and broader definition of life that includes these particles, but it's no consensus.

This list that attempts to define life is one that would probably exclude the very alien lifeforms, if find them. Would we even recognise them as living being based on that list if we did? Probably not. 

[xSilverPhinx]

for example, viruseas are certainly not cellular. but i don't see why that should be part of the definition. it's like defining life as containing chloroplasts. easy to do, but lots of things don't contain chloroplasts that fit the rest of the definition.

The interesting thing about chloroplasts (and mitochondria) is that they were once independent, living organisms, but seem to have lost their "alive" status as they became cell organelles. Talk about demotion! 

[xSilverPhinx]

I don't know either. One year of high school biology was enough to turn me off to squishy things. It's why I was a mechanic instead of a doctor, which career I did consider. I don't like the sight of blood at the tender age of 68 (especially my own), and I didn't like it then. I'd've felt like shit if a patient died, as well. I don't give a shit if a vehicle dies, though. It just goes to the junk yard...excuse me, vehicle dismantler/recycler. 

Heh, the sight of blood I can handle, it's the smell of blood that really bothers me.

[Old Seer]

When/if anyone actually brings life to an understanding and it can be concluded that knowledge to be correct, we may have to change our methods of life and existence. The question you ask shows that - it's not known. So then, that brings up the understanding that presently we could be very wrong. What's going to happen to society/civilization when we find out that we were incorrect and come to a knowing of what is" correct. Would the people's existing at that time be willing to make changes to accommodate what's been found to be correct. 

[billy rubin]

i didnt know that about chloroplasts

[Old Seer]

alien lifeseems to me to be a very likely occurrence

remember the drake equaton?

but when we'r elooking for civiliztions and wondering whether they're communicating, we're essentially lookign in the mirro and trying to see ourselves

what makes me curious is whether "civilization" is even a reasonable expectation. sure, we have a sample size of one, which is us, but that doesn't let us evaluate whether we're at all likely to find something that looks like we do. i keep thinking about all th eforms of highly evolved life for which our patterns of existence are totally irrelevant

https://www.youtube.com/watch?v=MOL10kuSt1s

^^this was as close as i could get to a video of a radiate organism without intrusive captioning. even here, we re trying to pigeonhole a form of life into a human system of clasification using names, sound, and a screenplay, all of which are superimpositions of human culture into a world where it doesn't exist.

what if life is recognizeable but unclassifiable?

what is"life," anyway? we're not even sure whether we should call a virus alive, or at least, I'm not.

Info from Bio Smurf. Life is "being". Being in two forms. You are a "being" because you exist mentally, also known as person, this would be the your spiritual side. Two-Being as "physical" life, a matter of a physical existence, our body is present therefore it "is'. A rock is also existing but it isn't biological, but it is being something (using common language). (Being is, you are as you at present). If you think and have bio functions ---that's life with the two present, each depending upon the other for existence of you .
  The result of that in manners of good or bad is --life, as in the saying of a happening---that's life. Life then is you as the result. A cell is physical life, but how can it be understood to be life as such, this may be a point of fact that may never be known. A cell depends on a chemical reaction between oxygen and a fuel producing heat along with other ingredients and components, after which we refer to as "life". Q- is life something other then the material components that make the cell and it's functions. 

[billy rubin]

im going to start playing in the metaphysics for a moment.

im not convinced that the animists were wrong. what if life is a normal characteristic of matter, like mass and volume, and is present in variable amounts, just as mass and volume, but maybe along a different axis?

this is a meaningless supposition unless having life also has something that corresponds to silver's list of biologically appropriate measures from ^^^above. after all, what's th epoint of calling a rock "alive" if it doesn't correspond to anything else that we call "alive?" this immediately brings up seer's question-- could "life" correspond to more than the biological list? here we run into both earthly ghosts and the questuon as to whether the stars sing for joy.

this is closely related in my mind to the idea of consciousness, since consciousness appears to be a characteristic of "higher" life--whatever that is-- and may therefore be a defining characteristicof life itself, present in difeent quantitites

[Old Seer]

im going to start playing in the metaphysics for a moment.

im not convinced that the animists were wrong. what if life is a normal characteristic of matter, like mass and volume, and is present in variable amounts, just as mass and volume, but maybe along a different axis?

this is a meaningless supposition unless having life also has something that corresponds to silver's list of biologically appropriate measures from ^^^above. after all, what's th epoint of calling a rock "alive" if it doesn't correspond to anything else that we call "alive?" this immediately brings up seer's question-- could "life" correspond to more than the biological list? here we run into both earthly ghosts and the questuon as to whether the stars sing for joy.

this is closely related in my mind to the idea of consciousness, since consciousness appears to be a characteristic of "higher" life--whatever that is-- and may therefore be a defining characteristicof life itself, present in difeent quantitites

From your OP it can be seen you are dealing with the two concepts that I mentioned. The material and the mental. So, when one is asking, what is life, it must be within the realm of of those two, because the universe doesn't contain anything else. Lets say for instance you omitted one and just stayed with the physical. Then that leaves a one concept that "life" can be discussed. But---you mentioned "civilization", that that brings  the mental into the picture as civilization is a product of thought. Biology as you well know studies and experiments with only one of these, the physical. The other of course is a matter of psychology. With that then, one must consider if each is of it's own realm but cannot get along without the other.
Example, the term psychosomatic, which means that the mental is causing a physical reaction for good or bad, and that is what PTSD is based on. And, at this time we've evolved into a "being" that is dependent upon both. In order to understand life both must be taken into account--because both have an effect on one's life.
It could/can be that the universe contains only material. That's if, thought patterns and the processes are electron patterns happening in the brain are mere formations of particles. Particles then, are material and the idea of a person is invisible (biblical extraction) and non  material wouldn't be true-with no way present to know if so.
Material itself is not life , bio or mental, but there is an arrangement when life is apparent through the processes that take place to allow it to exist from a material construct. Material came first because we know that it takes material to form the material structural processes for the mental to be. For the time being, (for me) life is what it takes to be alive. Life may not be a "what", it may be an "is".