What makes life?

[Cryopyre]

WHat makes life life? What is the definition of a living organism.

How about the virus debate, is something like a virus considered a living organism, it can reproduce, but it needs the aid of others.

How about the must basic life form that is not under debate, a single celled organism. It has no intellect, it is just a repeating clock of chemical reactions.

http://www.youtube.com/watch?v=_VxQuPBX1_U

here is a video that talks about us in the same way, simple chemical reactions.

Lastly, if we constructed a robot that could recreate itself without any intervention from other organism, would that constitute as life?


This may appear jumbled, so sorry, but these questions have bothered and confused me for quite a while.

[Cryopyre]

UGGHHH, the word game. I think we are going to find various opinions here. For me, it is anything organic with the ability to reproduce (despite the mechanism), respiration (despite the mechanism of aerobic or anaerobic, digestion, and growth.

Yes, the word game. Now, first of all, I'm going to assume organic means chemical compounds that evolved into life from non-life.

Now what is a virus, it has organic compounds, but it is unable to reproduce without a host.

Since it has yet to be shown that chemical compounds can evolve into life from non-life, I can't answer that one. I can only start with organic. I can't assume the cause of the organic since science has yet to make any real progress in that area.

If you recall, I included "despite the mechanism" when I listed reproduction as a part of the equation.

Okay, however, a virus does not have any other activity other than reproduction and destruction of other organisms. At least, that's what I think.

[Cryopyre]

So would this robot be able to evolve? I've heard of books that address this question, and it is very interesting, after all this machine that has the intelligence of, let's say, a fly, and this machine was able to reproduce, would it evolve a higher intelligence over the course of millions of years just as man did?

Then, if this potential for intelligence exists, does the ability to evolve then mean that it is alive?

It probably wouldn't evolve perse because it wouldn't need to. An intelligent AI would be capable of designing improved versions of itself, effectively leapfrogging evolution by thousands or even millions of years.

It isn't, however, an intelligent AI, it has the intelligence of a fly, it simply has a program telling it to survive and reproduce. Over a course of a million years or so, these robots would have had enough glitches in their programs accumulating to evolve into another animal.

Ah, missed the fly part. Well I suppose the survival part of the "survive and reproduce" part above is key. If the AI can only crank out carbon copies of itself then it cannot evolve. If, however, it's programming allows it to make subtle changes to itself in response to changes to it's environment, then effectively speaking it is evolving.

Well even if it produced carbon copies of itself wouldn't they evolve slowly at first, and maybe even acquire an epigenetic-like system.

What would be the mechanism for this evolution? If they are carbon copies that means they never change. No change, no evolution. There has to be options for natural selection to have something to select.

Well, aren't genetics, at least in early organisms supposed to produce carbon copies of themselves, they just fail in the long run because of mutations caused by radioactivity etc.

If that is the case, a program built to make carbon copies of each other would slowly change because of "mutations" in the program.

[Metatron]

So would this robot be able to evolve? I've heard of books that address this question, and it is very interesting, after all this machine that has the intelligence of, let's say, a fly, and this machine was able to reproduce, would it evolve a higher intelligence over the course of millions of years just as man did?

Then, if this potential for intelligence exists, does the ability to evolve then mean that it is alive?

It probably wouldn't evolve perse because it wouldn't need to. An intelligent AI would be capable of designing improved versions of itself, effectively leapfrogging evolution by thousands or even millions of years.

It isn't, however, an intelligent AI, it has the intelligence of a fly, it simply has a program telling it to survive and reproduce. Over a course of a million years or so, these robots would have had enough glitches in their programs accumulating to evolve into another animal.

Ah, missed the fly part. Well I suppose the survival part of the "survive and reproduce" part above is key. If the AI can only crank out carbon copies of itself then it cannot evolve. If, however, it's programming allows it to make subtle changes to itself in response to changes to it's environment, then effectively speaking it is evolving.

Well even if it produced carbon copies of itself wouldn't they evolve slowly at first, and maybe even acquire an epigenetic-like system.

What would be the mechanism for this evolution? If they are carbon copies that means they never change. No change, no evolution. There has to be options for natural selection to have something to select.

Well, aren't genetics, at least in early organisms supposed to produce carbon copies of themselves, they just fail in the long run because of mutations caused by radioactivity etc.

If that is the case, a program built to make carbon copies of each other would slowly change because of "mutations" in the program.

Which brings up the issue of whether a mechanical device is capable of mutation. Since mutation seems to occur because of copying errors in the genes during cell division or due to exposure to things like U/V radiation, chemical mutagens, and viruses, I'm not sure what the mechanism would be for machine based mutation.

[Metatron]

So would this robot be able to evolve? I've heard of books that address this question, and it is very interesting, after all this machine that has the intelligence of, let's say, a fly, and this machine was able to reproduce, would it evolve a higher intelligence over the course of millions of years just as man did?

Then, if this potential for intelligence exists, does the ability to evolve then mean that it is alive?

It probably wouldn't evolve perse because it wouldn't need to. An intelligent AI would be capable of designing improved versions of itself, effectively leapfrogging evolution by thousands or even millions of years.

It isn't, however, an intelligent AI, it has the intelligence of a fly, it simply has a program telling it to survive and reproduce. Over a course of a million years or so, these robots would have had enough glitches in their programs accumulating to evolve into another animal.

Ah, missed the fly part. Well I suppose the survival part of the "survive and reproduce" part above is key. If the AI can only crank out carbon copies of itself then it cannot evolve. If, however, it's programming allows it to make subtle changes to itself in response to changes to it's environment, then effectively speaking it is evolving.

Well even if it produced carbon copies of itself wouldn't they evolve slowly at first, and maybe even acquire an epigenetic-like system.

What would be the mechanism for this evolution? If they are carbon copies that means they never change. No change, no evolution. There has to be options for natural selection to have something to select.

Well, aren't genetics, at least in early organisms supposed to produce carbon copies of themselves, they just fail in the long run because of mutations caused by radioactivity etc.

If that is the case, a program built to make carbon copies of each other would slowly change because of "mutations" in the program.

Which brings up the issue of whether a mechanical device is capable of mutation. Since mutation seems to occur because of copying errors in the genes during cell division or due to exposure to things like U/V radiation, chemical mutagens, and viruses, I'm not sure what the mechanism would be for machine based mutation.

[Confused]

UGGHHH, the word game. I think we are going to find various opinions here. For me, it is anything organic with the ability to reproduce (despite the mechanism), respiration (despite the mechanism of aerobic or anaerobic, digestion, and growth.

Yes, the word game. Now, first of all, I'm going to assume organic means chemical compounds that evolved into life from non-life.

Now what is a virus, it has organic compounds, but it is unable to reproduce without a host.

Since it has yet to be shown that chemical compounds can evolve into life from non-life, I can't answer that one. I can only start with organic. I can't assume the cause of the organic since science has yet to make any real progress in that area.

If you recall, I included "despite the mechanism" when I listed reproduction as a part of the equation.

Okay, however, a virus does not have any other activity other than reproduction and destruction of other organisms. At least, that's what I think.

No, a good virus will just make its host suffer for a while, ie common strains of influenza etc... A bad virus (usually a new one such as HIV in its early phases ) will kill its host. A virus isn't necessarily only functioning to destroy other organisms, rather it is trying to survive. Viruses have long been theorized to be a perfect vehicle for introducing genetic sequences into human DNA to correct or minimize mis-translations/trancriptions. Is there another purpose for them? Time will tell. But not all viruses are bad. The influcence of disrupting a human genetic sequence with a viral DNA sequence could and does lead to anitgens formed to milder forms of viruses to provide immunity before exposure.

[Cryopyre]

UGGHHH, the word game. I think we are going to find various opinions here. For me, it is anything organic with the ability to reproduce (despite the mechanism), respiration (despite the mechanism of aerobic or anaerobic, digestion, and growth.

Yes, the word game. Now, first of all, I'm going to assume organic means chemical compounds that evolved into life from non-life.

Now what is a virus, it has organic compounds, but it is unable to reproduce without a host.

Since it has yet to be shown that chemical compounds can evolve into life from non-life, I can't answer that one. I can only start with organic. I can't assume the cause of the organic since science has yet to make any real progress in that area.

If you recall, I included "despite the mechanism" when I listed reproduction as a part of the equation.

Okay, however, a virus does not have any other activity other than reproduction and destruction of other organisms. At least, that's what I think.

No, a good virus will just make its host suffer for a while, ie common strains of influenza etc... A bad virus (usually a new one such as HIV in its early phases ) will kill its host. A virus isn't necessarily only functioning to destroy other organisms, rather it is trying to survive. Viruses have long been theorized to be a perfect vehicle for introducing genetic sequences into human DNA to correct or minimize mis-translations/trancriptions. Is there another purpose for them? Time will tell. But not all viruses are bad. The influcence of disrupting a human genetic sequence with a viral DNA sequence could and does lead to anitgens formed to milder forms of viruses to provide immunity before exposure.

Right, right, but what I meant was they only reproduce, they don't even digest food.

[Confused]

Right, right, but what I meant was they only reproduce, they don't even digest food.

But the abillity for a virus to insert itself into a bilogical cell to perform the actions negates the need for it to carry its own enzymatic functions. It is a parsite, but as it injects its own genetic code into the host cell, it takes over the functioning of that cell.

http://www.howstuffworks.com/virus-human1.htm

If you have read How Cells Work, you know how both bacteria cells and the cells in your body work. A cell is a stand-alone living entity able to eat, grow and reproduce. Viruses are nothing like that. If you could look at a virus, you would see that a virus is a tiny particle. Virus particles are about one-millionth of an inch (17 to 300 nanometers) long. Viruses are about a thousand times smaller than bacteria, and bacteria are much smaller than most human cells. Viruses are so small that most cannot be seen with a light microscope, but must be observed with an electron microscope.
A virus particle, or virion, consists of the following:

Nucleic acid - Set of genetic instructions, either DNA or RNA, either single-stranded or double-stranded (see How Cells Work for details on DNA and RNA)
Coat of protein - Surrounds the DNA or RNA to protect it
Lipid membrane - Surrounds the protein coat (found only in some viruses, including influenza; these types of viruses are called enveloped viruses as opposed to naked viruses)
Viruses vary widely in their shape and complexity. Some look like round popcorn balls, while others have a complicated shape that looks like a spider or the Apollo lunar lander.
Unlike human cells or bacteria, viruses do not contain the chemical machinery (enzymes) needed to carry out the chemical reactions for life. Instead, viruses carry only one or two enzymes that decode their genetic instructions. So, a virus must have a host cell (bacteria, plant or animal) in which to live and make more viruses. Outside of a host cell, viruses cannot function. For this reason, viruses tread the fine line that separates living things from nonliving things. Most scientists agree that viruses are alive because of what happens when they infect a host cell.
Inside the cell:
Once inside the cell, the viral enzymes take over those enzymes of the host cell and begin making copies of the viral genetic instructions and new viral proteins using the virus's genetic instructions and the cell's enzyme machinery (see How Cells Work for details on the machinery). The new copies of the viral genetic instructions are packaged inside the new protein coats to make new viruses.
Once the new viruses are made, they leave the host cell in one of two ways:

They break the host cell open (lysis) and destroy the host cell.
They pinch out from the cell membrane and break away (budding) with a piece of the cell membrane surrounding them. This is how enveloped viruses leave the cell. In this way, the host cell is not destroyed.
Once free from the host cell, the new viruses can attack other cells. Because one virus can reproduce thousands of new viruses, viral infections can spread quickly throughout the body.

Lysongenic Cycle
Once inside the host cell, some viruses, such as herpes and HIV, do not reproduce right away. Instead, they mix their genetic instructions into the host cell's genetic instructions. When the host cell reproduces, the viral genetic instructions get copied into the host cell's offspring. The host cells may undergo many rounds of reproduction, and then some environmental or predetermined genetic signal will stir the "sleeping" viral instructions. The viral genetic instructions will then take over the host's machinery and make new viruses as described above. This cycle, called the lysogenic cycle, is shown in the figure below.

In the lysogenic cycle, the virus reproduces by first injecting its genetic material, indicated by the red line, into the host cell's genetic instructions.


Because a virus is merely a set of genetic instructions surrounded by a protein coat, and because it does not carry out any biochemical reactions of its own, viruses can live for years or longer outside a host cell. Some viruses can "sleep" inside the genetic instructions of the host cells for years before reproducing. For example, a person infected with HIV can live without showing symptoms of AIDS for years, but they can still spread the virus to others.

[QED]

Which brings up the issue of whether a mechanical device is capable of mutation. Since mutation seems to occur because of copying errors in the genes during cell division or due to exposure to things like U/V radiation, chemical mutagens, and viruses, I'm not sure what the mechanism would be for machine based mutation.

It all depends no "what level of technology" you are considering. Agencies like NASA have already developed Evolvable Hardware wherein Genetic Algorithms generate designs for space hardware. Developing this technique one step further could result in Self-replicating spacecraft - or von Neumann probe. But whether these developments run on organic or inorganic platforms should be irrelevant if the products evolve self-awareness. I can't see the favouring of organic life over inorganic as anything other than an unwarranted prejudice based on our parochial outlook.

Self-awareness would seem to me to be the ultimate criteria for discerning life from non-life in my opinion. The problem would then be transferred to ascertaining in which atomic structures this property resides and where it does not. The temptation to say that it is obvious that a bunch of unfeeling parts cannot be assembled into a self-aware, and feeling structure, can be shown to be in error if we consider that we ourselves could not identify feeling in any of our constituent parts. Only if we go down the dualistic route and propose that particular, favoured, atomic structures become blessed with a metaphysical component that endows them with feeling, can we give in to the temptation.

[Metatron]

Which brings up the issue of whether a mechanical device is capable of mutation. Since mutation seems to occur because of copying errors in the genes during cell division or due to exposure to things like U/V radiation, chemical mutagens, and viruses, I'm not sure what the mechanism would be for machine based mutation.

It all depends no "what level of technology" you are considering. Agencies like NASA have already developed Evolvable Hardware wherein Genetic Algorithms generate designs for space hardware. Developing this technique one step further could result in Self-replicating spacecraft - or von Neumann probe. But whether these developments run on organic or inorganic platforms should be irrelevant if the products evolve self-awareness. I can't see the favouring of organic life over inorganic as anything other than an unwarranted prejudice based on our parochial outlook.

Part of my point was that mutation perse seems unlikely when we are talking about a self-replicating machine. However, a machine whose programming allows it to make modifications of its design to meet changes in its environment can effectively evolve. This Evolvable Hardware concept from NASA that you mentioned sounds like an interesting first step on this road.

Upon reading your reference to Von Neumann probes, I am both intrigued and somewhat disquieted by them. According to one of the parts of the article, these self-replicating probes, if sent out with no ingrained limitations, could multiply at a geometric rate and eventually essentially strip-mine the cosmos of materials for their continued creation. Kind of a scary idea.

Self-awareness would seem to me to be the ultimate criteria for discerning life from non-life in my opinion. The problem would then be transferred to ascertaining in which atomic structures this property resides and where it does not. The temptation to say that it is obvious that a bunch of unfeeling parts cannot be assembled into a self-aware, and feeling structure, can be shown to be in error if we consider that we ourselves could not identify feeling in any of our constituent parts. Only if we go down the dualistic route and propose that particular, favoured, atomic structures become blessed with a metaphysical component that endows them with feeling, can we give in to the temptation.

Since there is no proof as of yet of some metaphysical component that makes us who we are, namely the soul, there seems no reason to believe that self-awareness and emotions are impossible things to design into an artificial entity whether constructed of organic or inorganic matter. Obviously, whether these things CAN be created by man's design is also yet to be proven. Perhaps research into our brain's functioning and their application to artificial intelligence will answer some of these questions within our lifetime. If so, then the fun really begins because man will be faced with a number of tough ethical/moral choices as well as the practical choices of how man wants these discoveries to influence our lives.

[QED]

Part of my point was that mutation perse seems unlikely when we are talking about a self-replicating machine. However, a machine whose programming allows it to make modifications of its design to meet changes in its environment can effectively evolve. This Evolvable Hardware concept from NASA that you mentioned sounds like an interesting first step on this road.

That's exactly what I wanted to suggest. The focus is often too much on the individual. The concept of the probe is that it makes use of the material resources scattered throughout the Galaxy -- or maybe even the universe as a whole. With an effectively infinite supply of materials, evolution rates should be comfortably able to achieve the continuity required for total colonization.

Upon reading your reference to Von Neumann probes, I am both intrigued and somewhat disquieted by them. According to one of the parts of the article, these self-replicating probes, if sent out with no ingrained limitations, could multiply at a geometric rate and eventually essentially strip-mine the cosmos of materials for their continued creation. Kind of a scary idea.

It's a can of worms alright. It should, of course, be noted that life on this planet might be the result of this kind of colonization process. The machinery just happens to be on an elemental scale. The principle of evolution by natural selection is one grounded in universal logic so in the thermodynamic landscape afforded by our universe it seems rather inevitable that ripples of colonization will follow.

Since there is no proof as of yet of some metaphysical component that makes us who we are, namely the soul, there seems no reason to believe that self-awareness and emotions are impossible things to design into an artificial entity whether constructed of organic or inorganic matter. Obviously, whether these things CAN be created by man's design is also yet to be proven. Perhaps research into our brain's functioning and their application to artificial intelligence will answer some of these questions within our lifetime. If so, then the fun really begins because man will be faced with a number of tough ethical/moral choices as well as the practical choices of how man wants these discoveries to influence our lives.

You mean we get to "play God" No doubt this kind of thought experiment has taken place before (albeit in a far less technologically inspired fashion). It seems to have automatically fostered the notion that life is here for a purpose, which could indeed follow if we consider our own potential motives for creating von Neumann probes. But in the presence of natural ordering processes, we have no unbroken chain of creation to follow back to a prime motive so we must remain wary of anyone claiming to know otherwise.