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Full Version: The "why life does not really exist" proposal: It's a concept we invented
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https://blogs.scientificamerican.com/bra...lly-exist/

EXCERPT: . . . Even today, scientists have no satisfactory or universally accepted definition of life. While pondering this problem, I remembered my brother’s devotion to K’Nex roller coasters and my curiosity about the family cat. Why do we think of the former as inanimate and the latter as alive? In the end, aren’t they both machines? Granted, a cat is an incredibly complex machine capable of amazing behaviors that a K’Nex set could probably never mimic. But on the most fundamental level, what is the difference between an inanimate machine and a living one? Do people, cats, plants and other creatures belong in one category and K’Nex, computers, stars and rocks in another? My conclusion: No. In fact, I decided, life does not actually exist.

[...] Formal attempts to precisely define life date to at least the time of ancient Greek philosophers. ... In the 17th century, German chemist George Erns Stahl and other researchers began to describe a doctrine that would eventually become known as vitalism. ... Subsequent experiments revealed vitalism to be completely untrue—the inorganic can be converted into the organic both inside and outside the lab. Instead of imbuing organisms with “some non-physical element,” other scientists attempted to identify a specific set of physical properties that differentiated the living from the nonliving. Today, in lieu of a succinct definition of life ... widely used biology textbooks include a rather bloated list of such distinguishing characteristics...

[...] It’s almost too easy to shred the logic of such lists. No one has ever managed to compile a set of physical properties that unites all living things and excludes everything we label inanimate. There are always exceptions. Most people do not consider crystals to be alive, for example, yet they are highly organized and they grow. Fire, too, consumes energy and gets bigger. In contrast, bacteria, tardigrades and even some crustaceans can enter long periods of dormancy during which they are not growing, metabolizing or changing at all, yet are not technically dead.

[...] Why is defining life so frustratingly difficult? Why have scientists and philosophers failed for centuries to find a specific physical property or set of properties that clearly separates the living from the inanimate? Because such a property does not exist. Life is a concept that we invented. On the most fundamental level, all matter that exists is an arrangement of atoms and their constituent particles. These arrangements fall onto an immense spectrum of complexity, from a single hydrogen atom to something as intricate as a brain. In trying to define life, we have drawn a line at an arbitrary level of complexity and declared that everything above that border is alive and everything below it is not. In truth, this division does not exist outside the mind. There is no threshold at which a collection of atoms suddenly becomes alive, no categorical distinction between the living and inanimate, no Frankensteinian spark. We have failed to define life because there was never anything to define in the first place.

I nervously explained these ideas to Gerald Joyce on the phone, anticipating that he would laugh and tell me they were absurd. After all, this is someone who helped NASA define life. But Joyce said the argument that life is a concept is “perfect.” He agrees that the mission to define life is, in some ways, futile. The working definition was really just a linguistic convenience. “We were trying to help NASA find extraterrestrial life,” he says. “We couldn’t use the word ‘life’ in every paragraph and not define it.”

Carol Cleland, a philosopher at the University of Colorado Boulder who has spent years researching attempts to deliniate life, also thinks that the instinct to precisely define life is misguided—but she is not yet ready to deny life's physical reality. “It’s just as premature to reach the conclusion that there is no intrinsic nature to life as it is to define life,” she says. “I think the best attitude is to treat what are normally taken as the definitive criteria of life as tentative criteria.”

[...] Recognizing life as a concept in no way robs what we call life of its splendor. It's not that there's no material difference between living things and the inanimate; rather, we will never find some clean dividing line between the two because the notion of life and non-life as distinct categories is just that—a notion, not a reality. Everything about living creatures that fascinated me as a boy are equally wondrous to me now, even with my new understanding of life. I think what truly unites the things we say are alive is not any property intrinsic to those things themselves; rather, it is our perception of them, our love of them and—frankly—our hubris and narcissism. [...] Truthfully, that which we call life is impossible without and inseparable from what we regard as inanimate. (MORE - details)
“It is a slightly arresting notion that if you were to pick yourself apart with tweezers, one atom at a time, you would produce a mound of fine atomic dust, none of which had ever been alive but all of which had once been you.”
― Bill Bryson, A Short History of Nearly Everything
I love philosophy but sometimes, I think we over-analyze.

I’m not really here, I just think I am.....

*tin foil hat on my head as I breathe deeply ...downward dog on my yoga mat*

^_^
You could make that same fallacious atomistic argument about anything...even atoms don't "exist" when broken down into elementary particles.

We have very workable definitions for life. Just like we don't really know what an atom is other than our descriptions of what it does. It's composed of particles, but are those particles really strings, loops, or something else? For this article's perspective, we have no satisfactory definition for anything. The ultimate postmodern theory.
(Jul 13, 2019 12:49 AM)Magical Realist Wrote: [ -> ]“It is a slightly arresting notion that if you were to pick yourself apart with tweezers, one atom at a time, you would produce a mound of fine atomic dust, none of which had ever been alive but all of which had once been you.”
― Bill Bryson, A Short History of Nearly Everything

Right. We are all composed of atoms and molecules, but the atoms and molecules aren't alive and never were.

Of course we could say the same thing about a television or an automobile. We could take each one apart and reduce it to a pile of parts, and none of those parts would be a television or a car.

So how are wholes composed of parts? (It's a fundamental metaphysical question.) There's clearly something more involved than the arithmetical sum of the parts all tossed in a pile. There are the parts' relations for one thing. How they are configured. A specific combination of parts might perform a function that requires all of them behaving in concert.

And that's where I would look for a definition of life. Not so much in some seemingly occult property of the individual parts (charged with life force!) but in how the parts are related, how they behave together and what functions they collectively accomplish.

(Jul 12, 2019 08:23 PM)C C Wrote: [ -> ]EXCERPT: . . . Even today, scientists have no satisfactory or universally accepted definition of life.

That's true of most of our most familiar words and concepts. (What is "truth"? Or "reality"? Or "good"?) It's really only mathematics where words and symbols receive precise definitions.

Quote:While pondering this problem, I remembered my brother’s devotion to K’Nex roller coasters and my curiosity about the family cat. Why do we think of the former as inanimate and the latter as alive? In the end, aren’t they both machines?

Maybe, if we accept one view of biology. (One that I happen to share.)

But the fact remains that there's a huge category of these kind of super-complex systems (including us) that occur naturally on Earth. (The cat would belong in that category.) And much more recently, there's been a far smaller category of vastly simpler systems that bear some analogy to the naturally occurring ones (things that move under their own power, that might process simple data and so on) that depend for their existence on the creative and constructive activity of the naturally occurring systems.

Quote:Granted, a cat is an incredibly complex machine capable of amazing behaviors that a K’Nex set could probably never mimic. But on the most fundamental level, what is the difference between an inanimate machine and a living one? Do people, cats, plants and other creatures belong in one category and K’Nex, computers, stars and rocks in another?

Well, one is naturally occurring, self-reproducing, subject to natural selection and Darwinian-style evolution, infinitely more complex and sophisticated and shares many molecular biological details. I see nothing false or illusory in conceptualizing that class and giving it a name ("Life").

Quote:My conclusion: No. In fact, I decided, life does not actually exist.

In my opinion, that's just foolish.

Quote:[...] Formal attempts to precisely define life date to at least the time of ancient Greek philosophers. ... other scientists attempted to identify a specific set of physical properties that differentiated the living from the nonliving. Today, in lieu of a succinct definition of life ... widely used biology textbooks include a rather bloated list of such distinguishing characteristics...

That's probably the best that anyone can do. Life comes in many different forms from bacteria to us. It's doing all kinds of different things, adapted to an endless number of ecological niches. So about all that one can do is try to extract some common denominators. But these probably shouldn't be imagined as if they were Aristotelian essences.

Quote:It’s almost too easy to shred the logic of such lists.

It is? It seems to me to probably be the only intelligent way of going about distinguishing life from non-life.

Quote:Why is defining life so frustratingly difficult? Why have scientists and philosophers failed for centuries to find a specific physical property or set of properties that clearly separates the living from the inanimate?

I agree that there probably isn't any single property. But a set? I don't think that this author's argument succeeds there.

Quote:Because such a property does not exist. Life is a concept that we invented.

All of our concepts are things that we invented. That doesn't mean that the world that we use our concepts to refer to doesn't exist. (That's a literary theorist's conceit.)

Quote:On the most fundamental level, all matter that exists is an arrangement of atoms and their constituent particles. These arrangements fall onto an immense spectrum of complexity, from a single hydrogen atom to something as intricate as a brain. In trying to define life, we have drawn a line at an arbitrary level of complexity and declared that everything above that border is alive and everything below it is not. In truth, this division does not exist outside the mind.

Except that life is naturally occurring, self-reproducing, has phylogenetic relationships with all of the rest of life and seems to be descended from a common ancestor (LUCA), uses nucleic acids on pretty much the same way, has broadly similar cellular metabolism and cell membranes. maintains homeostasis... and on an on.

Quote:There is no threshold at which a collection of atoms suddenly becomes alive, no categorical distinction between the living and inanimate, no Frankensteinian spark. We have failed to define life because there was never anything to define in the first place.

That might work if it was an argument against vitalism.

Quote:I nervously explained these ideas to Gerald Joyce on the phone, anticipating that he would laugh and tell me they were absurd. After all, this is someone who helped NASA define life. But Joyce said the argument that life is a concept is “perfect.” He agrees that the mission to define life is, in some ways, futile. The working definition was really just a linguistic convenience. “We were trying to help NASA find extraterrestrial life,” he says. “We couldn’t use the word ‘life’ in every paragraph and not define it.”

I doubt very much that Joyce was endorsing this writer's foolish assertion that since 'life' is a concept, that means that life doesn't exist. My guess is that Joyce was looking at it from an exobiological perspective. Life on Earth seems to have had a common origin, but extraterrestrial life won't share that origin. Earth life uses nucleic acids, protein synthesis and so on in similar ways. Extraterrestrial life living in frigid seas of methane might not share those commonalities.

Our problem is that when we set out to define what life is in a way that's applicable throughout the universe, we only have a sample of one: Earth life.

So we can try to invent more abstract criteria that even alien life would have to meet to be considered life, but that isn't easy.

I expect that's Joyce's point. If we are too locked-in to some particular definition of Earth life, we might not even recognize that alien life is life. Alien life might not have any DNA for example, so if we are using DNA as a criterion of life, we might dismiss it as not being life at all. But it might perform a similar function in some unexpected way. A possibility that suggests that we need to move in the direction of functional abstraction.

Quote:Carol Cleland, a philosopher at the University of Colorado Boulder who has spent years researching attempts to deliniate life, also thinks that the instinct to precisely define life is misguided—but she is not yet ready to deny life's physical reality. “It’s just as premature to reach the conclusion that there is no intrinsic nature to life as it is to define life,” she says. “I think the best attitude is to treat what are normally taken as the definitive criteria of life as tentative criteria.”

That's probably all we can do at this point. Life probably doesn't have a single Aristotelian essence, applicable throughout the universe. It probably does share many things in common: reproduction, metabolism, evolution etc., but might have come at those very broad functions in very different ways. Recognizing alien life might be more a matter of recognizing a family resemblance than determining if it satisfies some precise definition. So yes, we probably should treat our criteria as tentative, and be willing to learn as our sample size grows (if it ever does).