Life

Originally posted by Andrew Hamilton
I agree that this must be generally true because I assume that the vast majority of people wouldn’t be so unreasonable to define a lump of rock as “living” because that would just be giving a meaning to the word that deviates by an unreasonable extend from what people normally mean by the word.

But, hypothetically, some extremely awkward unreasona ...[text shortened]... in his own mind.
-still, I think you are right -I shouldn’t have said “purely” subjective 🙂

Funnily enough, I actually don't think this is so unreasonable. I'm not saying that we should start studying rock figurines in biology class, but have you ever noticed how easy it is to ascribe lifelike properties to inanimate objects? Cartoons, puppets, mannequins, robots and sometimes even pet rocks all give us the impression from time to time that they are alive, even if we would never consciously label them "alive" using a hard-science definition.

According to Steven Pinker, a proponent of the computational model of the mind, humans have several identifiable "modules" or intuitive thought processes that developed as quick and dirty solutions to the problems faced by our evolving ancestors. A few of the proposed modules include: intuitive physics, intuitive engineering (tool identification, use and fashioning), intuitive psychology, intuitive spatial sense (for organizing and keeping track of objects), intuitive number sense (for rough counting and size comparison), etc... Intuitive biology is also included on the list. With respect to its functioning, Pinker writes:

"- An intuitive version of biology or natural history, which we use to understand the living world. Its core intuition is that living things house a hidden essence that gives them their form and powers and drives their growth and bodily functions." (Pinker, "The Blank Slate", p.220)

A module like this would help explain why some cultures cling to the notion of widespread animism, where the "life essence" is embedded in nature (water, trees, wind, even rocks), and it would also help explain why most religions centre around the notion of a "soul" as the driving force in human action and interaction, a "soul" which makes a person "alive" and persists into the afterlife because of the strong memory of the person's personality or "soul" which also persists with the bereaved. It's possible that cartoons, puppets, mannequins, robots and sometimes even pet rocks constructed to remind us of certain key properties we recognize in people or animals (eyes, mouths, facial expressions, human-like movement, and in the case of pet rocks blissful sloth 😉) trigger a reaction in our intuitive biology modules giving us the uncanny feeling that our favourite stuffed animal or cartoon character just might be "alive".

For those of you (including me) wanting to discuss life in a spiritual aspect of view, I have opened a thread "Spark of life" in the Spiritual Forum: Thread 104942. Now we can continue to discuss life here in its scienctific aspects without going off-topic.

Originally posted by Palynka
An article about it:
http://www.astrobio.net/news/article226

It's interesting how something which seems so easy to grasp intuitively is actually very hard to pin down. Is life much less different from non-life than our intuition tells us?

It seems to me that Life cannot be solely identical to a biolgical phainomenon, thus it cannot be specified solely with regards to the biological phainomenon itself -and this is the reason why it remains unconceivable to the Science. So the Science is unable to determine in full what is Life although it does offer scientific explanations regarding the evolution of the Life on Earth.

Originally posted by Andrew Hamilton
[b]…But why not just define “life” as anything which has either undergone Darwinian evolution or at least has the potential for Darwinian evolution (regardless of whether or not it is “self-sustaining&rdquo😉?
The first problem is that evolution is defined in a way that requires genes and
.…

Actually not quite -remember that when Darwinian evolu ...[text shortened]... in his own mind.
-still, I think you are right -I shouldn’t have said “purely” subjective 🙂[/b]

Am I the only one that thinks that Darwinian evolution is an outdated term? Evolution theory has gone beyond Darwinism.

Actually not quite -remember that when Darwinian evolution was first conceived there was no knowledge of the existence of “genes” and yet evolution was still defined.
Note that in that point I'm addressing the concept of "gene" simply as a unit of heredity. This is a very vague definition which also contains the first example you provide. The thing is, evolution cannot work without basic units of heredity, so although you might define it without referring to genes, you are implicitly admitting their presence.

I am always puzzled to why so many people don’t want viruses to be defined as “living” -personally I see viruses as “living” because of what I vaguely mean by “life” -but that is just me.

Virus are certainly a sort of a puzzle. However, I do think it is weird to consider an entity that cannot metabolize nor reproduce as "alive". If I were to search one property of living things that I find "essential", it would have to be metabolism. Of course, I'm not a biologist...

Originally posted by PBE6
Funnily enough, I actually don't think this is so unreasonable. I'm not saying that we should start studying rock figurines in biology class, but have you ever noticed how easy it is to ascribe lifelike properties to inanimate objects? Cartoons, puppets, mannequins, robots and sometimes even pet rocks all give us the impression from time to time that they are ...[text shortened]... our favourite stuffed animal or cartoon character just might be "alive".

I think that's a different issue. If you notice, not only are those properties lifelike, but they're usually also anthropomorphic. We also apply such anthropomorphism to animals and plants (the dog is smiling, the cat is vain, etc.). I think it relates to more of a relationship between human/non-human than between living/non-living.

If I seem a bit contrarian here, it's not because I think everybody is wrong, but just to express my own doubts and see how you would address them. I'm not arguing for the sake of arguing, though, just that I'm focusing more on what we disagree on, as it is there that I can potentially learn the most.

Originally posted by Palynka
Am I the only one that thinks that Darwinian evolution is an outdated term? Evolution theory has gone beyond Darwinism.

[b]Actually not quite -remember that when Darwinian evolution was first conceived there was no knowledge of the existence of “genes” and yet evolution was still defined.
Note that in that point I'm addressing the concept of "gene" s ...[text shortened]... at I find "essential", it would have to be metabolism. Of course, I'm not a biologist...[/b]

…Am I the only one that thinks that Darwinian evolution is an outdated term? .…

I am surprised you think that -in your mind, in what way do you think Darwinian evolution is an ‘outdated’ term?

…Evolution theory has gone beyond Darwinism.…

Are you merely pointing out the fact here that the various aspects of the theory have been elaborated on since Darwin’s time? -I think the core or essence of the theory hasn’t changed fundamentally since then.

…Note that in that point I'm addressing the concept of "gene" simply as a unit of heredity. This is a very vague definition which also contains the first example you provide. The thing is, evolution cannot work without basic units of heredity, so although you might define it without referring to genes, you are implicitly admitting their presence....

If, hypothetically, some self replicating robots where released into the environment and evolved with the information about each robots inherited characteristics being stored only in software, then wouldn’t it be a bit inappropriate to describe the evolution of such robots by referring to “genes” as it is not immediately obvious what constitutes a particular “gene” in that scenario?
-true, to properly define evolution you must make a reference to “heredity” (or at least imply the word) but “heredity” doesn’t necessarily imply there must be some entities in existence that you could appropriately label as “genes”.

…Virus are certainly a sort of a puzzle. However, I do think it is weird to consider an entity that cannot metabolise nor reproduce as "alive". If I were to search one property of living things that I find "essential", it would have to be metabolism. Of course, I'm not a biologist.…

I believe that your suggestion that something must “metabolise” to be “alive” is neither right or wrong because it depends on what you really mean by “alive” -if one of the essential things for something to be “alive” in your mind is for it to metabolise, then, to you, to say something must “metabolise” to be “alive” is a factually correct assertion.

-but that should mean that, even with what you mean by “alive”, viruses are “alive”!
This is because it is not quite technically correct to say viruses don’t “metabolise” -true they don’t have any meaningful “metabolise” while they are not actually inside a living cell hijacking the living cell’s metabolism, but, when they are inside a living cell hijacking the living cell’s metabolism, they are doing more than just using the living cell’s metabolism, they unravel their own DNA/RNA and then self replicate that and, also, they hijacking the living cell’s metabolism to make their own proteins that are normally not the same kind of proteins that are naturally part of the cell’s metabolism. Some of these viral proteins then interact to build the various parts of new virus particles that are copies of the original -this is part of what is called “viral metabolism”.

Originally posted by Palynka
I think that's a different issue. If you notice, not only are those properties lifelike, but they're usually also anthropomorphic. We also apply such anthropomorphism to animals and plants (the dog is smiling, the cat is vain, etc.). I think it relates to more of a relationship between human/non-human than between living/non-living.

I think the main purpose of the biological module is just to separate things that may try to eat you (living) from those that won't (non-living). The psychological module is supposed to help you deal specifically with people. Things that move tend to trigger the "living" response, but only in so far as they move unpredictably, or seemingly without regard to physics (i.e. a ball rolling down a hill doesn't trigger it, but a ball rolling down a hill, stopping, and then rolling back up the hill seemingly of its own accord does). Anthropomorphic attributes (like the appearance of a dog's smile, or a cat's endless preening) will usually trigger this response, but the strongest response undoubtedly stems from objects that appear to posses a "will". This is probably the most anthropomorphic attribute we ever use, but it is distinct from simple visual resemblances.

The only reason I brought all this up in the first place is that I don't think there's anything fundamentally different between living and non-living things in terms of their basic building blocks. Of course, living systems do behave differently than non-living systems due to the arrangement of those building blocks, and it may be useful to categorize systems as either "living" or "non-living" to make various predictions about their future behaviour, but because there are so many ways to arrange the building blocks into systems that exhibit certain (but not all) aspects of what researchers call "life", I don't think the definition will ever be cut-and-dried. It appears to be more of a continuum, from "definitely non-living", along "probably non-living" and "partially living" to "probably living" and "definitely living". I think our intuition fools us because it's programmed to make quick and dirty decisions about life, so definitions along a continuum give us the nagging feeling that we're missing something.

We're all part of the same closed system. I think it is a mistake to try to separate objects within a closed system based on one objects understanding of itself.

"alive" "Not alive" are irrelevant. We should recognize that all objects in our system are comprised of the same basic material and therefore "alive" and "not alive" are relative terms that are meaningless on the grand scale.

All objects form part of the larger whole. The universe exists, and therefore we are the Universe.


This conversation sounds like a bunch of toes trying to debate whether the hair on a person's body are the same or different than they are.

We're all part of the same system! We are the body!

Originally posted by Palynka
Heredity. You also seem to forget that we're talking about evolution in the biological sense. Like I said, this is only defined for living organisms, rendering it's use, for defining life, circular by construction.

Computer models can implement heredity. Of course the definition is circular, the question is, what's the circle?

Originally posted by KazetNagorra
Computer models can implement heredity. Of course the definition is circular, the question is, what's the circle?

No, it can't. It can only simulate it because heredity is a property of living organisms.
http://en.wikipedia.org/wiki/Heredity

Originally posted by Palynka
No, it can't. It can only simulate it because heredity is a property of living organisms.
http://en.wikipedia.org/wiki/Heredity

There is a branch of programming called 'genetic' programming where you start with a set of rules on how you want a particular outcome, say a better cellphone antenna, then let it start with a simple dipole and introduce small changes/mutations and let it run and it indeed comes up with innovative solutions never thought of by any engineer. By definition, it is an improvement so it sounds like evolution to me.
Can we define what non-life is, to do the other half of the equation?

Originally posted by sonhouse
There is a branch of programming called 'genetic' programming where you start with a set of rules on how you want a particular outcome, say a better cellphone antenna, then let it start with a simple dipole and introduce small changes/mutations and let it run and it indeed comes up with innovative solutions never thought of by any engineer. By definition, ...[text shortened]... s like evolution to me.
Can we define what non-life is, to do the other half of the equation?

A professor in genetic programming showed a demonstration of genetic programming.
He defined a set of rules of aquadynamics, and building blocks initially two boxes connected with a joint, movements in this joint, and the outcome to move as quickly as possible through water.
The result was very amazing! Wiggeling, and screwing, and methods of swimming I don't know the name for.
Every time he started the program from anew, the outcome were different. Some very animal like, some very innovative, but always different result.

This is simulated evolution in action! Here it takes a moment, in nature it takes millions of years.

Originally posted by Palynka
An article about it:
http://www.astrobio.net/news/article226

It's interesting how something which seems so easy to grasp intuitively is actually very hard to pin down. Is life much less different from non-life than our intuition tells us?

A very interesting question!! I'm inclined to think that only through life, can matter begin to understand it's creator. 😏

Originally posted by bill718
A very interesting question!! I'm inclined to think that only through life, can matter begin to understand it's creator. 😏

So your anti-science agenda shows through, interested only in proving your sick god is the creator.