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    Can Science Define Life In Three Words?
    By Carl Zimmer | January 11th 2012 08:31 PM | 88 comments | Print | E-mail | Track Comments
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    Carl Zimmer has written hundreds of articles for the New York Times and magazines including National Geographic, Time, Scientific American, Science...

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    In November 2011, NASA launched its biggest, most ambitious mission to Mars. The $2.5 billion Mars Science Lab spacecraft will arrive in orbit around the Red Planet this August, releasing a lander that will use rockets to control a slow descent into the atmosphere. Equipped with a “sky crane,” the lander will gently lower the one-ton Curosity rover on the surface of Mars.

    Curiosity, which weighs five times more than any previous Martian rover, will perform an unprecedented battery of tests for three months as it scoops up soil from the floor of the 96-mile-wide Gale Crater. Its mission, NASA says, will be to “assess whether Mars ever was, or is still today, an environment able to support microbial life.”

    Curiosity rover: Will it know life if it finds it? Courtesy: NASA

    For all the spectacular engineering that’s gone into Curiosity, however, its goal is actually quite modest. When NASA says it wants to find out if Mars was ever suitable for life, they use a very circumscribed version of the word. They are looking for signs of liquid water, which all living things on Earth need. They are looking for organic carbon, which life on Earth produces and, in some cases, can feed on to survive. In other words, they’re looking on Mars for the sorts of conditions that support life on Earth.

    But there’s no good reason to assume that all life has to be like the life we’re familiar with. In 2007, a board of scientists appointed by the National Academies of Science decided they couldn’t rule out the possibility that life might be able to exist without water or carbon. If such weird life on Mars exists, Curiosity will probably miss it.

    Defining life poses a challenge that’s downright philosophical. There’s no ambiguity in looking for water, because we have a clear definition of it. That definition is the same whether you’re on Earth, on Mars, or in intergalactic space. It is the same whether you’re dealing with water as ice, liquid, or vapor. But there is no definition of life that’s universally agreed upon. When Portland State University biologist Radu Popa was working on a book about defining life, he decided to count up all the definitions that scientists have published in books and scientific journals. Some scientists define life as something capable of metabolism. Others make the capacity to evolve the key distinction. Popa gave up counting after about 300 definitions.

    Things haven’t gotten much better in the years since Popa published Between Necessity and Probability: Searching for the Definition and Origin of Life in 2004. Scientists have unveiled even more definitions, yet none of them have been widely embraced. But now Edward Trifonov, a biologist at the University of Haifa in Israel, has come forward with a new attempt at defining life, based on a new strategy. Rather than add on yet another definition to the pile, he’s investigating the language that previous scientists have used when they talk about life.

    Edward Trifonov: Life is self-reproduction with variations.

    Trifonov acknowledges that each definition of life is different, but there’s an underlying similarity to all of them. “Common sense suggests that, probably, one could arrive to a consensus, if only the authors, some two centuries apart from one another, could be brought together,” he writes in a recent issue of the Journal of Biomolecular Structures and Dynamics (article PDF).

    In lieu of resurrecting dead scientists, Trifanov analyzed the linguistic structure of 150 definitions of life, grouping similar words into categories. He found that he could sum up what they all have in common in three words. Life, Trifonov declares, is simply self-reproduction with variations.

    Trifonov argues that this minimal definition is useful because it encompasses both life as we know it and life as we may discover it to be. And as scientists tinker with self-replicating molecules, they may be able to put his definition to the test. It may be possible for them to create a system of molecules that meets the requirements. If it fails to come “alive,” it will show that the definition was missing something crucial about life.

    Trifonov’s editors at the journal invited a number of other scientists who study the origin of life to issue their verdict on Trifonov’s definition. Judging from their responses, it doesn’t look like anyone’s ready to link arms and sing Kumbaya over their beakers of primordial soup. Popa, for example, questions whether the best way out of the definitional bind is to look for consensus. “It does apply very well to fields where basic research has more or less ended, yet it makes it difficult for pioneers and novel theories to gain recognition, irrespective of how right they are,” he writes (article PDF). If science is nothing but a popularity contest, ideas like plate tectonics might have never been discovered and confirmed.

    A number of the scientists who responded to Trifonov felt that his definition was missing one key feature or another, such as metabolism, a cell, or information. Eugene Koonin, a biologist at the National Center for Biotechnology Information, thinks that Trifonov’s definition is missing error correction. He argues that “self-reproduction with variation” is redundant, since the laws of thermodynamics ensure that error-free replication is impossible. “The problem is the exact opposite,” Koonin observes: if life replicates with too many errors, it stops replicating. He offers up an alternative: life requires “replications with an error rate below the sustainability threshold.”

    Jack Szostak, a Nobel-prize winning Harvard biologist, simply rejects the search for any definition of life. “Attempts to define life are irrelevant to scientific efforts to understand the origin of life,” he writes (article PDF).

    Szostak himself has spent two decades tinkering with biological molecules to create simple artificial life. Instead of using DNA to store genetic information and proteins to carry out chemical reactions, Szostak hopes to create cells that only contain single-stranded RNA molecules. Like many researchers, Szostak suspects that RNA-based life preceded DNA-based life. It may have even been the first kind of life on Earth, even if it cannot be found on the planet today.

    Life, Szostak suspects, arose through a long series of steps, as small molecules began interacting with each other, replicating, getting enveloped into cells, and so on. Once there were full-blown cells that could grow, divide, and evolve, no one would deny that life had come to exist on Earth. But it’s pointless to try to find the precise point along the path where life suddenly sprang into being and met an arbitrary definition. “None of this matters, however, in terms of the fundamental scientific questions concerning the transitions leading from chemistry to biology,” says Szostak.

    It’s conceivable that Mars has Earth-like life, either because one planet infected the other, or because chemistry became biology along the same path on both of them. In either case, Curiosity may be able to do some good science when it arrives at Mars this summer. But if it’s something fundamentally different, even the most sophisticated machines may not be able to help us until we come to a decision about what we’re looking for in the first place.

    Originally published on Txchnologist.com. Republished with permission.

    Carl Zimmer has written hundreds of articles for the New York Times and magazines including National Geographic, Time, Scientific American, Science, and Popular Science. He is the author of ten books about science, most recently Science Ink: Tattoos of the Science Obsessed.

    Since 2003, he has written the award-winning blog The Loom.

    Comments

    Hank
    Since this is a guest post by Carl, he may have login fatigue and not want to log in and respond in another place, so you can comment on Txchnologist or at his Discover home.  Or Twitter. Or Facebook...or here anyway, of course.

    It's his first guest post here but he's no stranger. Here he is accosting Bloggy with Jennifer Ouellette and Kirsten 'Dr. Kiki' Sanford at an AAAS conference - which is a pretty good way to go, for a stuffed bear.

    ‎"Intelligence recognizes what has happened. Genius recognizes what will happen." -John Ciardi
    GO TO MY BLOG about pressure systems: https://ciscosphere.wordpress.com/category/uncategorized/
    Cellular life is a pressure system manifested from other systems of pressure.
    Nassim Haramein is also a genius. He predicted that someone (me) would PROVIDE a simple explanation. AND it also predicts many other things. There is no GOD, no Higgs Boson, No escape from all reality realized in the Universe.
    For Love of humanity, we can now direct all efforts to poverty, homeless, sickness, Thank You, Francisco Martinez (me)
    Ultimate Truth is that: Pressure = Energy (conserved,giving or taking) which eventually leads to the chance for cellular life only in a slim window of chance. We cannot escape this reality!

    Gerhard Adam
    LOL
    Mundus vult decipi
    Gerhard Adam
    How about "exploits [not simply uses] its environment".  After all, wouldn't we expect to see some environmental modification occurring as a result of a life form, regardless of how small, that would suggest that the environment is being exploited to support the life form itself?  Unlike other chemical reactions that simply utilize resources until they are expended, life tends to utilize chemistry to "advance" itself.

    Even in the case of oscillating chemical reactions, there is no other purpose except to continue driving the reaction, however life always transforms those processes into something more.
    Mundus vult decipi
    The MatrixDNA

    Gerhard, so, what about this definition: Life in three words is “self-reproductive opened systems”?

    I am watching my theoretical model of a complete working closed natural system and making comparisons with an opened system. What has changed between the non-living astronomical system and the life of biological systems that arose inside the first? The opening of an ancestral closed system and the evolution of self-recycling mechanism towards self-reproduction. I can’t see here anything else. That’s the basic for the definition of life above. As about exploitation, of external environment, it is only performed by an opened system. What do you think?   

    Gerhard Adam
    I'm afraid you're going to have to give me a more complete definition of what you mean by an "open" system.  Life doesn't appear to have such characteristics from any definition of "open systems" I've ever seen or heard about, so I need to know how you are using it.

    Bear in mind, that life itself is fundamentally about keeping itself segregated from its environment and only selectively bringing in resources it needs and expelling those it doesn't.  Therefore, certainly at the cellular level, it would be hard to argue that there's anything "open" about the process.
    Mundus vult decipi
    The MatrixDNA

    Ok, you are right, thanks.  I will give up because 1) I am not seeing how a human definition of life in three words could help Curiosity; 2) As it is impossible for our little brain processing the complex information of an ultimate thru – it is impossible to human language translating into intelligible communication the natural phenomenon called “life”. 3) Short definition of life is a philosophical issue that will not help Biology facing real phenomena. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

    I am just now seeing the diagram of a kind of life that does not need water and carbon, moreover, performing all life’s properties in a mechanical level of matter organization.  I am sure about something: all kind of organized matter, be it alive or not, need be a system. A part, pieces, does not presents the requirements for being alive. Our problem is again – the language and the definition of system: what people are calling “systems”, like the interaction between H1 and O2 forming a water molecule is not a system in my viewpoint; the interaction is merely a process. A real perfect closed system presents at least seven parts performing the seven universal systemic functions. Opened system are those that two or more systemic functions are poorly performed because it is aggregated in a unique part forcing the system making changes with external world. Biological animal systems are opened systems because they miss the tool for the last function, which makes chloroplasts and photosynthesis in vegetal systems. But vegetal is only half system because they exploit matter for growing (while a perfect system does not - and does not grow, has no variations) and a vegetable needs another half system for reproduction (while perfect system recycles itself). For example, when you say that living cellular system is not an opened system because it only aggregates matter, I will say that it is opened system because interacts with the external world and every kind of life give back to the environment everything that it had absorbed. But, giving up to the search of a short definition, does not means giving up to the event about Curiosity, we can continuing it with my following  post:  

               

    The MatrixDNA

    Curiosity mission is “to assess whether Mars ever was, or is still today, an environment able to support microbial life.” It remembers Oparin and Stanley/Miller experiments. What kind of “state of the world"  is suitable for arising life? We don’t know how was the state of Earth at life’s origins, since that all experiment trying to reproduce those conditions is missing something. It is missing the ingredient that leads amino acids to next step, composing proteins by themselves. If the Matrix/DNA theoretical models are rights, the mysterious ingredients are (half of them) coming from Sun’s radiation and another half, from the planet’s nuclear radiation. But I am not seeing how Curiosity could grasp it. Maybe taking pictures and transmitting to us working atomic systems, searching if they present abnormal behavior, but it seems technologically difficult.

    Maybe Curiosity will walk among the parts of a living thing without grasping that it is “alive”, if the theoretical models are right: only spherical balls and tornadoes in the space with only the gaseous and solid states of matter can performs all life’s properties and be a living thing. Included being conscious..., maybe. Can pieces of rock and/or amount of gas over planet’s surface interacts as living thing? It is possible. So, Curiosity should be equipped with instruments for capturing signals of interactions. But the interactions of processes dominates the planet and should be noises, perturbations turning difficult the search. It needs capturing only the signals of interactions among parts of systems. Again, I think that animated software of the Matrix/DNA inserted into Curiosity as template, should help to recognize any similar interactions. I don’t know if it is technically possible.

    The seeds of life are everywhere being transmitted by stars and planets’ nucleus. They flourish where there is a good, suitable, land. But, the seeds do not came as a whole. They came as bits of a Matrix software. How to identify if a land, a territory, is a good hardware for receiving, capturing and operating those bits, in the way that the bits can leads atoms to combinations that re-composes the software? I don’t know, I should ask help here to someone like Bill Gates: he understands about relationships between hardware and software.

    Gerhard, we cannot leave the poor Curiosity alone in that hell working for us without knowing what search for. We need doing our parallel mission here, burning our neurons and quickly…
    Steve Davis
    There's only one problem in defining life, and that's the inability of people to think logically.
    Too many confuse the functions of life, metabolism homeostasis and reproduction, with the definition of life. 
    To find a definition we have to look at the essence of the functions, and in the case of life its essence can be defined in three words; independent spontaneous cooperation, as explained here.
    We can refer to "the life of a group" and "the cooperation of a group" and the terms are synonymous.
    Gerhard's introduction of exploitation is useful, but I think too general, as the terms "life of a group" and "exploitation of a group" are not synonymous, they require explanation.
    Mr. Steve … You have a very good point but you can improve it. The independent spontaneous cooperation when is dependent of a lot of elements (several types of molecules, the 20 aminoacids, etc) is difficult if have no hidden directionality. And if one element does not cooperate, we should have no biological life. It is more difficult in a changing environment, where chaos is present, and self- cooperation should be impossible.

    My models are suggesting that while the earlier land environment was changing, the first prototype of life could live in homeostasis because were feeding from something that was not changing: Chemosynthesis/photosynthesis with energy coming from sun and/or earth’s nucleus.
    There was cooperation, but non spontaneous. Inside the primordial soup there was photons-bits-information from energy coming from a ancestor astronomic closed system. These photons inside atoms works like virus inside cells, they driven the machinery and to new systemic organizations. Then, the primordial elements were infected with a genetics that imposes cooperation to the parts. I know that it is difficult to understand a never saw worldview resulted from a different method and written in poor English…
    But your insights has helped me testing my results, maybe mines can help you thinking new insights. Cheers…

    Steve Davis
    Louis, thanks for your thoughts.
    You said, "And if one element does not cooperate, we should have no biological life. It is more difficult in a changing environment, where chaos is present, and self- cooperation should be impossible." Difficult, yes. Impossible, no, because we are here, after all.
    You are on the right track when you talk of systemic organizations.
     Life is not something material.
    Talk of photons and elements and atoms and nuclei, only confuses the issue.
    Life is a process. 
    What is the best way to describe this particular process?
    Cooperation.
     
    Steve, life can be not material being natural. Like computers are visible hardware and invisible software, both encrypted in the machine, both natural, but one (software), is driven by another "allien" system performing the natural hierarchy among natural systems.

    Instead “life’s process” I bet in “natural systemic’s process”. My theoretical models are suggesting that from atoms to galaxies to cells, there is a systemic cycle: every new cycle begins with chaos (conflict among systems), intermediate equilibrium with grow (cooperation), order ( super-specialism and accommodation), degeneration (dissolution), chaos (with mutation and transcendence), new species of system, and go on…
    If you focus over one phase you’ll not grasp the whole. I am sure that my process above is not complete. The systemic cycle must be fit with seven variables and I pointed only five. The template for a systemic cycle came from a unit of life’s cycle with is imprinted into matter by the variables vibrations of a light ray spectrum. The best model is a nucleotide: four central variables, a fifty recycling variable (uracil), and two fixed elements (two sugars) which became variables among nucleotides. Cooperation alone does not explain everything, I think, but I could be wrong. It could be hidden important elements, like the step from order to chaos, where the particles of the fragmented hardware suffers a kind of will for re-organization which I call the will for change for transcendence. It is like when Bill Gates is not satisfied with the limitations of the hardware that does not operates the new more complex software he has in mind. Then, I am suspecting that there is a hidden element in this process, a kind of natural software. If we think that cooperation is the final answer, we will not looking for any possible hidden element.

    Steve Davis
    Louis, your attempt to see the big picture to the life process is to be admired, but I get the impression that you are more concerned with the origins of life rather that defining what life actually is. We need a definition of life that is simple, that fits all levels of systems, and that can be used to assess alien life if any exists. Independent spontaneous cooperation fits those requirements. As someone once said, "If you can't state it simply you don't know enough about it" or something along those lines. Cheers
    The MatrixDNA

    Steve, how Curiosity will search for life under this instruction: “Search independent spontaneous cooperation”...  ?  How to grasp that an atom, or a bunch of atoms, is emitting signals to another atoms and receiving signals that can be identified as channels of cooperation?  I know that my question is infantile and you have thought about it, but, if you can to explain it I will be grateful.  By another hand, I suggest that, if Curiosity is equipped with a working, animated image, of the universal formula for any kind of life, from electro-magnetic to mechanical to biological organization of matter, like the Matrix/DNA formula, I think that if has any resonance at Mars’ surface with that image, Curiosity will grasp it. What do you think?  

    Louis, you are in the right direction. It takes a genius to know this. I hope you have received my messages I have sent you through your site. I have also contacted Nassim Haramein (theresonanceproject.org)
    EVERYONE: YOU CANNOT PASS THIS UP: It's my blog. I have the explanation and language that ties in everything that exists and is visible. It's all energy and potential of energy because everything we observe is in a captive system of balance of pressure (Energy). https://ciscosphere.wordpress.com/category/uncategorized/
    The secrets are coded in the geometries etched in crop circles and mandalas. They are the blueprints of the steps/phases of evolution/transformation of manifestation. The steps, phases of systems of all manifested PRESSURE. My explanation is not complete yet. But it is clear that it is the Ultimate Truth. Pressure = Energy (conserved,giving or taking) which eventually leads to the chance for cellular life.

    Gerhard Adam
    Delusion makes all answers seem simple.
    Mundus vult decipi
    The MatrixDNA

    Francisco, thanks, and I will pay attenption to your theory. I think it is my obligation remembering you about something:

    1) I am not grasping how your short definition of life could help Curiosity identifying life elsewhere. Can you explain it to me?

    2) Our little human brain is not able to grasp the ultimate thru. Because the brain’s logics and real knowledge inserted into the brain leads our mind to an ultimate question with only two alternatives:  or this world began from nothing, or this world exists eternally.  Do you know a third alternative? I don’t, if you know, please tell me. But our brain/mind is not capable of processing a world under any of those two alternatives.  A world existing from all times is not possible; it needs a beginning, but, from nothing can not coming something.  So…?  Must have a third alternative, and no human brain can process this information. In my website I have a charter about Nassin’s insights, really it is wonderful, but is far from the ultimate thru, yet.

    If the secrets (the third alternative) are coded in the geometries of mandala, etc., it means that were inserted there by a non-human brain.  But, this alien brain did it for what?  If we never will use it because we cannot process it?!

    You have a good insight, you have a theory, but it is about one aspect of the whole, it is not the whole. Like my theory of Matrix/DNA never will be the ultimate thru, and if has something right on it, it will be only a little aspect of ultimate thru. But here is the value of continuing the search and not believing in ultimate thru: this search exercises our brain, theories are guides for new experimentations, new discoveries, in this way walks evolution, the evolution towards our transcendence. The transcendence of our actual shape, the acquiring of a new powerful  brain, which, then, maybe will be able for discovering the third, the fourth, and so on,  alternatives, till arriving to the final ultimate thru… if there is one. Cheers…

    Gerhard Adam
    ...as the terms "life of a group" and "exploitation of a group" are not synonymous...
    Not quite sure where you're going with this.  My point is simply that individual or group, makes no difference, it is in their ability to exploit their "environment" to advance themselves that the traits of life become manifest.

    You might also consider that the environment could be another living system, such as bacteria within a human host or viruses within a cell.  To each of these organisms, the "environment" happens to be another living organism or system. 
    Mundus vult decipi
    Steve Davis
    Gerhard, the problem with your use of "exploitation" is that it only describes the link between the living entity and its environment. It describes the link, it does not define the essence of the living entity, which is what we are trying to do.
    Gerhard Adam
    Exactly the point.  In other words, a modified environment is indicative of the existence of life.  Within life itself, I'm using the concept of "exploitation" as a directed activity to maintain itself, so unlike other chemical reactions, life exhibits the use of such processes in a controlled and/or repeatable manner.

    Basically my point is that all living things share a common trait ... they must bring in outside resources to maintain their internal chemistry and they must dispose of extraneous or irrelevant byproducts.  It is in this sense, that I mean "exploit".

    Also, I'm using it to differentiate simply "using" the environment like a fire "uses" wood or oxygen to burn. 
    Mundus vult decipi
    Steve Davis
    Gerhard, I agree with everything you have said, except that what you describe is merely a feature of living entities, as is homeostasis for example. It does not define what life itself is.
    You are describing the entity, not life.
    Gerhard Adam
    Perhaps the problem here [as with those that look for a philosophical definition] is that the purpose of this particular question is to use it as a basis for detecting life on other planets.  As a result, I'm focusing on what particular trait or process should we be able to see that would indicate such an existence. 

    An example I've often considered is watching rocks rolling down a hill.  Normally we just consider them rocks acting under the force of gravity.  However, if we suddenly observed them veering in different directions with the intent of specifically hitting us [the observer] then I think most of us would conclude that there is something directing these rocks and probably conclude that they were "alive".
    Mundus vult decipi
    Steve Davis
    Exactly so, Gerhard.
    Except that for the rocks to "suddenly veer" it would require some form of internal cooperation between the rock's constituent parts.
    So the veering is the trait, the essence of the veering is the cooperation.
    Life needs to be able to replicate on its own, which is why viruses, prions, transposons, etc. are not really life. They are, at best, "life-like." But, precisely defining, "What is life?" is more a philosophical exercise than biologically useful.

    Gerhard Adam
    I think the reproduction angle is too specific.  There is no requirement that an living organism be capable of reproducing, beyond the fact that they age and die [for the forms we know of]. 

    If we discovered cells that were, for all practical purposes, "immortal", why impose the need to reproduce on them?

    It is also worth considering that when life originated on this planet, reproduction would not have been an established process.  In all likelihood, any cells "dividing" would have been accidental and ad hoc.  Yet, we wouldn't think to argue that it wasn't actually life, simply because a reproductive mechanism wasn't already functional and in place.

    More specifically, to argue that viruses are not alive is stretching the boundaries of the definition, because since they are not only capable of exploiting the cell's machinery, but have explicit "knowledge" of the means to do so, requires that they be living [since, they exploit their environment, i.e. the cell] whereas prions do not.
    Mundus vult decipi
    Yes, it is for us that love philosophical exercise. There is something not alive that can replicate itself. When a stellar system dyes, its degraded matter composes a nebulae that becomes a new star system. What is name of this process: self-recycling, self-replication or self- reproduction?

    Then the evolution of this process comes from the non living world from Physics laws. Viruses cannot replicate because they are not a complete natural system, mere parts. Biological systems are the ones that evolved the self-recycling to self-replication and I know why. It is all about chirality, another long history.

    Gerhard Adam
    There is something not alive that can replicate itself.
    There are many non-living things which can replicate, so it doesn't add much to the conversation.
    Mundus vult decipi
    Really? Non-living natural systems able for self-replication?! Please. I am researching this issue and if you tell me which they are, I will be grateful. I know about, for example, crystals grows, divides, but crystal are not systems like star or atoms systems.

    Gerhard Adam
    How are crystals not systems?  In any case, DNA molecules are certainly non-living, and can replicate.  Depending on how you want to define replication, you can argue that everything from prions to fire are essentially self-replicating if the raw materials are available.
    Mundus vult decipi
    Interesting! We began searching a definition for life and now we are in troubles searching a definition for system. It is not a surprise. There is a problem with the word “life”. Universal evolution has been the evolution of a unique system that was born at the Big Bang. It was a kind of vortices, and vortices has all life’s properties in state of brutes forces. Then it makes no sense calling an atom or astronomical system non living and bacteria alive: the difference is at the level of organization of matter, electro-magnetic, mechanical or biological system.

    Same way there was no origins of life, since that there were no emergency of new systemic property.
    The simplest definition of system ( Wikipedia: system is a set of interacting or interdependent components forming an integrated whole) is not right because the key elements in a system are the functions of parts and the identity of the system. You know: in a system the parts lose their identities because the sum of informations of all parts plus the new information from fuzzy logic derivated from the connections became the identity of the system, which exerts pressure over the parts. In my website you can see a diagram of a natural closed system and I am in trouble trying to find a short definition.

    Crystals are not systems, mere a mass of sub-systems, atoms. There is no nucleus, no parts performing the seven universal functions.

    DNA is a curious intermediary situation. It is a mass of systems – nucleotides – but nucleotides composes parts, the genes, and the whole set of genes could be a system. But DNA replicates because the blueprint of system inherited from the galaxy system: each half face composes another half-faces because the internal circuit has information for a complete face.

    Gerhard Adam
    Crystals are not systems, mere a mass of sub-systems, atoms.
    Sorry, but that's simply a tautology.  Despite your usage here, a "subsystem" is a system that is merely subordinate to a higher system.  It makes it no less a system.
    Mundus vult decipi
    The MatrixDNA

    Interesting! We have different understanding about systems, but you are right, accordingly to the definition in Wikipedia. Wikipedia is written by academic modern official scientific thought which is the best for Humanity given the success of its products. Educated by Nature in the jungle, and interested in observation of natural systems, I can’t understand  “yours” definition in Wikipedia.

    To me the Wikipedia definition confuses “system ”with “process”. To me system is matter organized in the way that has nucleus, division among different parts that performs different functions, etc. In a crystal, which different groups of atoms can be called “parts” and which specific function each part executes?

    Who will be the ultimate judge between us? Only the time, when we will know what dark matter is. By your definition, the whole Universe is a system that must be a subsystem merely subordinate to the higher system, in which it is immersed: dark matter. This analogy is valid because you say that any system is a subsystem immersed and subordinated to a higher system. Is dark matter a system composed by subsystems? I bet that it is not, but… I am nobody for to criticize the definition universally elected just now.
    Steve Davis
    "But, precisely defining, "What is life?" is more a philosophical exercise than biologically useful."
    That's like saying that the search for truth is irrelevant to biology. Which is a fair assessment of the history of evolutionary biology, but I don't think that is what was implied.
    A definition of life is useful if it enables us to identify life that is not based on carbon and water, an issue raised in the article.
    The definition of spontaneous independent cooperation satisfies that requirement. 
    Gerhard Adam
    The definition of spontaneous independent cooperation satisfies that requirement.
    While you know that I agree with the dominance of cooperation in biology, I can't really support this particular statement [within this context].  The primary problem I see is that it presumes the existence of more than one organism.  Regardless of how prevalent such a trait may be, if we're considering fundamental definitions, then we must consider the possibility of a single organism existing as a precursor to whatever may follow.  Therefore, at some point in the origin of life, there would have been some time [even if quite short] where life existed, despite having nothing to "cooperate" with.

    In other words, we must consider the possibility of long-lived [if not "immortal"] organisms that have no need to reproduce, nor interact with each other.  In such a sparse limited existence, there may be life without cooperation.

    Mundus vult decipi
    Steve Davis
    "In other words, we must consider the possibility of long-lived [if not "immortal"] organisms that have no need to reproduce, nor interact with each other. In such a sparse limited existence, there may be life without cooperation."
    Not at all Gerhard.
    You've overlooked the internal processes of the living entity.
    The consituent parts of a cell, for example, cooperate. The cells cooperate.
    So there could hypothetically be a single instance of life forming somewhere in the universe, that did not reproduce, but its underlying essence would still be cooperation.
    Gerhard Adam
    I don't think you're going primitive enough.  If you look at the prokaryotes and note the absence of organelles, it's entirely possible for life to consist of a "sack of chemicals" with nothing more sophisticated beyond a means of taking in and expelling chemical products.

    Once again, this is why I'm using the term "exploit" as a means of differentiating a "directed" set of chemical processes versus simply an uncontrolled set of reactions.
    Mundus vult decipi
    Steve Davis
     "...with nothing more sophisticated beyond a means of taking in and expelling chemical products."
    That's a process that involves accessing energy, using energy, distributing energy, expelling waste, etc. The process is cooperation.
    Whether there was a big bang or not, we are not concerned for the purpose of nailing down 3 words that define LIFE. Whatever fabric of space and the nature of it, was prepared for life to happen is not yet important as in terms of defining LIFE as fundamental as you'd like. First, there was movement of matter through what we refer to as outer space (dark matter/vacuum). The scattered matter attracted (gravity) to each other and formed all sorts of celestial bodies. We are concerned with the path for the possibility of LIFE. More concentrated matter (higher PRESSURE towards the center point of "singularity") formed stars which shed (LIGHT) and created magnetic fields to fully develop its own solar system with planets. As a result of all the PRESSURE interactions in the Earth's core, the right combination of physiological interactions created (WATER). From this point on only time and other cycles produced as a result, the right pressures (temperatures) to form an atmosphere suitable first for microbes and whatever other evolutionary theories you want to apply, gave chance for the evolution and existence of LIFE.

    As it concerns Human LIFE, we survive because of Pressures in our various systems (heart), The LIGHT that continues to shine sustains LIFE to continue to sustain plant life which many other forms of life depend on. And the WATER that was developed is crucial to sustain and prolong the final creation of physical LIFE in the history of these PRESSURE, LIGHT, and WATER cycles.

    (The final result of the cycle of LIFE is cancer, disease and evil)

    And finally and ultimately, wisdoms of good intention (mostly Religions) exist to guide us and develop into decent and loving human beings. If we don't, an even higher cycle of evolution in LIFE (Human Life) is in the human mind as a result of our inventions and the many creations throughout human history that can poison our minds and that can and have created the chance for cancer, diseases, and evil to develop.

    Gerhard Adam
    Life isn't just about humans. 
    Mundus vult decipi
    Very interesting! You are advocating that there is a new universal constant: pressure. Inclusive the action of moral and religious is a kind of pressure.
    There is another situation where we can see pressure driving evolution: the feed-back between software and hardware. The increase in complexity of software exerts pressures for more complex hardware. Better hardware leads to capture new information, which is grasped by the human mind that transfers these information to the software.
    This is just what the results of my method of comparative anatomy between living and non-living systems are suggesting: the Universe is composed by hardware and software working in feed-back. Nature does need a mind transferring informations between hardware and software, because the software is encrypted in the hardware, pure genetics. My models suggest what is and how is the software of atoms and astronomical systems: the systemic circuit of flow of energy works like a flow of information and has the shape of a diagram of software.

    But how the ancestor galaxy system that produced the hardware-biological system transferred its software to Earth’s surface? Mechanic genetic process: entropy produces photons-bits information that works like genes when emitted by stellar radiation.

    You made me earning my day, thank you! This universal constant, pressure, needs to be added to my work. And you have a discovery that can result in a good book.

    Thank You Louis. I have come to terms that you are soundly right. But I don't believe pressure itself is a constant. Since nothing is perfect in the Universe, I would say that pressure is a near constant variable. The constant existence and nature of it brought about LIFE. I would say it is a variable in every system because of its dynamically constant effects in parent systems. I made a discovery through imagining the nature of PRESSURE and all of its manifestations that are clearly evident to mankind. Water and Light are irreputably unavoidable in describing and explaining the nature of LIFE, also in all of its manifestations. It is everywhere that you try to imagine and/or has resulted from a previous event, cycle or system of pressure. Even in human day-to-day activities. Inside your body, in the atmosphere of planets. In organic cells, there is pressure and they move about in fluid material. It takes pressure for a baby to be born. Clearly in software, as you suggest. The need for faster computers because of pressure from competition, company survival, etc also drives the need for better software and hardware to create near instantaneous communication between systems. A great and similar example is the need for faster and higher energy colliders in the quest to find the Higgs particle (GOD particle) as we know has already just recently begun. All because of pressure from a surrounding system(s) or within a system(s) that has or is already at work. In tandem or harmony if you will. I could definitely write a book about it. For now, stay connected with me on my blog: https://ciscosphere.wordpress.com/category/uncategorized/

    "Curiosity, which weighs five times more than any previous Martian rover, will perform an unprecedented battery of tests for three months as it scoops up soil from the floor of the 96-mile-wide Gale Crater."

    The primary mission is actually a full Mars year, which is almost two Earth years. The MERs were the ones with the 90 day mission, and Opportunity is still alive and kicking on sol (Mars day) 2834. If Curiosity comes even close to that sort of performance, it will have a very very long time to search for biomarkers.

    blue-green

    Exploit, exploit, exploit!

    Sounds harsh perhaps …. until you define exploitation and realize it is biology.

    http://www.kansascity.com/2011/12/17/3317510/commentary-rise-of-the-jellyfish.html

    “Providing for one’s family as a good husband and father is a water-tight excuse for making money hand over fist. Greed may be a sin, exploitation of other people might, on the face of it, look rather nasty, but who can blame a man for “doing the best” for his children?”
    Eva Figes (b. 1932), Anglo-German author. “A View of My Own,” in Nova (Jan. 1973).

    “Exploitation and oppression is not a matter of race. It is the system, the apparatus of world-wide brigandage called imperialism, which made the Powers behave the way they did. I have no illusions on this score, nor do I believe that any Asian nation or African nation, in the same state of dominance, and with the same system of colonial profit-amassing and plunder, would have behaved otherwise.”
    Han Suyin(b. 1917), Chinese author. The Crippled Tree, pt.1, ch. 9 (1965).

    “Self-reproduction with variations” doesn't cut the mustard because it gives no clue as to how it is achieved.

    Gerhard Adam
    I don't think your particular examples are appropriate, because they don't describe anything specifically to do with biology, and instead attempt to rationalize exploitation within the same species.  While there is competition within a species, there is rarely outright exploitation of other individuals [within the same group]. 

    We have to be careful here, because this is precisely the kind of argument that was raised by the eugenics movement and various rationalizations to explain how the status quo is biologically justified.  It's a false equivalence.
    Mundus vult decipi
    blue-green

    Where is Carl Zimmer? Seems a bit irrational that he would abandon us.

    As the unofficial fortune cookie slip-writer here, I am all in with the 3 word challenge.

    Gerhard, right above you wrote that I “attempt to rationalize exploitation within the same species.”

    Perhaps you did not open the link about the giant jelly fish. Here it is again:

    http://www.kansascity.com/2011/12/17/3317510/commentary-rise-of-the-jell...

    It is a huge cross species story. If Hank does not yet have the unfolding story at Science 2.0, let's get it on.

    Gerhard, 99% of the time I find your input at Science 2.0 to be “spot on”. Your feedback here has been contradictory and irrational. Further up, in your own suggestion on how to distinguish the essential parameters of life you write:

    “How about "exploits [not simply uses] its environment". After all, wouldn't we expect to see some environmental modification occurring as a result of a life form, regardless of how small, that would suggest that the environment is being exploited to support the life form itself?”

    After I seize upon your insight with “exploit, exploit, exploit!” you say “I don't think your particular examples are appropriate, because they don't describe anything specifically to do with biology, and instead attempt to rationalize exploitation within the same species.”

    The jelly fish example is a perfect and current example of exploitation across species. How many more examples do you want? Why the irrationality in your feedback? Is it a symptom of you being alive?

    Thanks to the clues you have set, I now have a TWO word definition of life. Without further ado and another 500 words to anticipate your plea for a definition of irrational, I'll give it to you now.

    Life = Irrational Exploitation.

    Directly above Gerhard notes: “While there is competition within a species, there is rarely outright exploitation of other individuals [within the same group].”

    Are you kidding? Is this an irrational moment for you Gerhard? Question: how did so much Inca gold end up gilding cathedrals in Spain? 

    OK. Define “group”.  When a divorce case comes to court, Gerhard implies that neither party pleas that they have been exploited.  When a crime or injustice is committed, police know that the prime suspects are “family members” within the immediate group. Crazy. That's why I define life with the pocket phrase: irrational exploitation.

    (Gerhard, with your last sentence above you veer off on a crazy tangent … symptomatic of life as we know it.)

    Here is another two-word definition of life (with a nod to Alan Greenspan):

    Irrational Exuberance!

    Gerhard Adam
    Your link regarding jellyfish doesn't appear to work [it shows page not found].

    The exploitation you keep bringing up is cultural or social and relates exclusively to humans competing within their social group(s).  While they occur within the human life experience, they are not definitive regarding life as a general principle. 

    Gaining additional gold to gild a cathedral isn't biological in any context.  Divorce isn't a biological concept, neither is crime.  These are social events within human society and are cultural.  While you can certainly argue that they may be involved [to varying degrees] with respect to competitive for sexual selection, they are not biological in the sense of "exploitation of the environment" that would be useful in a definition.

    If you wish to demonstrate that there is exploitation within a group [in this case; species], then people present something other than humans.  The point is quite specific regarding social groups, because at that point, the group itself may be considered a kind of "super-organism" whose behavior needs to be analyzed, rather than simply observing the individuals in it.  However, exploitation [as I mean it] is not simply aggression, advantage, or competition.  It is specifically intended to describe the situation of where something is "used" to achieve some biological objective for the organism in question. 

    In that respect, we "exploit" oxygen for respiration.  We "exploit" other species as food.  We "exploit" other resources for construction, etc.  In short, we take from our environment [including other species] for the express purpose of our particular biological needs [after all, this is a definition of life]. 
    Mundus vult decipi
    blue-green
    Gerhard's 7 word confession of life (slightly adapted from above):

    We take from others to please ourselves.  

    ((the clickable link works fine in my browser .... google chrome))
    Gerhard Adam
    Mundus vult decipi
    Gerhard Adam
    Where did you get that interpretation?  Where would you conclude that "pleasure" was a factor?
    Mundus vult decipi
    Bonny Bonobo alias Brat
    Well I tend to agree, my three words to define life are PAIN, PLEASURE, PAIN.
    My article about researchers identifying a potential blue green algae cause & L-Serine treatment for Lou Gehrig's ALS, MND, Parkinsons & Alzheimers is at http://www.science20.com/forums/medicine
    blue-green
    Same jelly-fish article by Fred Grimm is here in the ever changing www. I saw a related special on TV! Try googling Jelly Fish and Nuclear Power .... with the date function set to within the last month.

    http://www.mcclatchydc.com/2011/12/17/132941/commentary-rise-of-the-jellyfish.html 
    Gerhard Adam
    OK, I've looked at the story.  I'm somewhat familiar with the rise of jellyfish blooms, but I'm not clear on the point you're trying to make.  Certainly if it's just to illustrate how changes in one area can create opportunities for others, I'm in complete agreement.
    Mundus vult decipi
    Curiosity will search for biological life. But it could be equipped for searching non-biological life also, in places at Mars’ surface that there is not liquid state for chemical reactions. And we can make these equipments.

    How Nature created life? There was – at 10 billion years ago – a unique kind of astronomical body resulted from the aggregation of primordial atoms. This body was being transformed by a physical force that came from the spectrum of light, and we call this law as “life’s cycles”. The life’s cycle makes that a body has transformations of shapes, then, the seven principal shapes were planets, pulsar, quasar, comet, supernova, red giant, black hole. The Universe was populated by these shapes. The next step is the same that human beings created the familiar system, by symbioses. Seven shapes aligned in the same sequence of a body under life’s cycle, then Nature got a system.
    I designed this system and discovered that it has all life’s processes in a mechanic way.

    But this system was created only with the solid and gaseous state of matter, where there is no organic chemistry. Attacked by entropy and fragmented in its bits-information, if these bits fall in a place where there is the liquid state, they reproduces the astronomic system in a biological fashion. It is nanotechnology, that’s the explanation of microbial life.
    I am alone testing this model because nobody, neither me, can believe in it. But, it was made 30 years ago, and the following scientific discoveries matches with its previsions. Then I am looking for scientific data, and collecting thousands of evidences.

    If the secret behind life’s origins lies in this model, there is no way to define life, as postulated by Gödel’s theorem: no one can define a system from inside the system. We are inside a cosmological system that seems alive.

    I have extracted the circuit of both systems – biological and astronomical – and discovered that it has the same configuration of nucleotides. It means that astronomical systems have DNA also, or in another words: every natural system has a Matrix/DNA. Then, Curiosity shall be equipped with a template of this model of Matrix for to search for life that does not use organic chemistry.

    blue-green

    Steve's three word definition: “independent spontaneous cooperation” ….. fits a spring. What a spring does is a process that in Steve's words: “involves accessing energy, using energy, distributing energy, expelling waste, etc. The process is cooperation.”

    Sorry Steve. Neither your definition nor “self-reproduction with variations” cuts the mustard. They give no clue as to how their processes are achieved.

    As long as you fellows ignore the irrationality of life and pretend it is rational and logical, you'll be confined to rational physics and chemistry ~ in a single word ~ springs ~ or as our standup physicist calls them ~ Lagrangians. (I once suffered through a graduate level economics class in which the professor tried to use Lagrangians ... for which he was clueless as to how to implement .... yet it impressed his students). 

    No humor, no life. No tragedy, no life.

    If you retort that I'm "describing the entity, not life," ... I'll eat Gerhard's hat.

    Steve Davis
    "Steve. Neither your definition nor “self-reproduction with variations” cuts the mustard. They give no clue as to how their processes are achieved." I thought you might at least take the trouble to read the article I wrote on this matter. I did provide a link, after all. And your spring idea does not fit the independent cooperation definition at all. Motion by springs has to be initiated by an outside agency. It is therefore not independent. With your "irrational exuberance" definition, followed by your red herring spring, it's obvious that you are trivialising a serious subject. Well done.
    blue-green
    You are not seriously offering to listen to my critique your article. It uses the word "independent" only once and it is in your 3-word phrase. Life is independent of nothing. Self-reproduction can simply be an oscillation. Variations are insured by the 2nd Law .... heat sinks.
    Steve Davis
    "Life is independent of nothing." Like I said above, the only problem in arriving at a definition of life is the inability of people to think logically. Give me a serious refutation of my article or go away.
    blue-green

    None of the molecules in a spring know that they are part of a greater whole, and yet they respond and quiver in tune with environmental impulses as though they were cooperating to preserve their greater form in some form of homeostasis.

    An engine is more complicated than aspring, yet it is still a mechanical device running on logical and classical physics.

    Although life may house many engines and springs, it is according to Steve not the sum of these parts.

    “an engine demonstrates cooperation between its various parts to achieve a particular end, but we would only refer to it as being alive in a metaphorical sense, as an engine needs external inputs for initiation and for sourcing of energy. The limitations of the engine example however, lead us in the right direction for a general definition. We can conclude as a general rule that independent spontaneous cooperation is life.”

    The keystone in this logical leap is that living things do not need “external inputs for initiation and for sourcing of energy” …. they are independent and spontaneous.

    It was my bad to deny that living systems “need external inputs for initiation and for sourcing of energy.” Forget that they are open system and need also to shunt used energy, per the 2nd Law.

    Deep in the comments, Gerhard surmises that Steve's means that living things can “obtain their energy means by their own volition (or motivation).”

    This is Gerhard skating close to free-will which he has relegated to fiction in other posts.

    Yes, countries and citizens declare their independence. It is a comforting illusion.

    Steve clarifies by saying, “they collect the energy themselves, as in a plant collecting energy from the sun, or a human or other animal society organising the external collection and internal distribution of energy.”

    That sounds like they EXPLOIT their environment, but I'm mistaken.

    If Steve's touchstone for life is worth anything, then it has consequences. Perhaps it can shed some light on whether free-will is a distinguishing characteristic of life or merely an illusion.

    Maybe the touchstone dissolves when it delves into real issues.

    Can it answer the question as to whether life is special and different from say a rainbow? I predict that Steve will consider my query about free-will to be a red-herring. He does a lot of predictable non-spontaneous things.

    And what about his highfalutin cooperation? If everyone simply cooperated, we would be mere cogs in a machine. There would be no innovation. Cooperation is what all rulers wish from their subjects. It never lasts long. It is never perfect, not even at the molecular level. Those spontaneous independent streaks are about as hard to bottle …. as a short lived radioactive substance … which would be yet another counter-example.

    I can hear him howl and see him patting himself on the back for his water-tight argument while he rests in the certainty that I'm an idiot. Bringing opposites like cooperation and spontaneity and independence in a definition is a good way to cover all the bases. Is it a rational way to reason about something? If he is being so logical, why does he have to remind us: “the only problem in arriving at a definition of life is the inability of people to think logically.”

    For each of Steve's three founding attributes for life, their opposites are also symptomatic of life, individually and all together.

    Steve concludes his short essay with “Life is far more basic and easier to explain than consciousness, and the very simplicity of the definition given here has consequences that might have contributed to the reluctance of some to delve toodeeply into its meaning. But that is another story.”

    ...

    My apologies for delving.

    Gerhard Adam
    What on earth are you talking about?  I won't get into your debate with Steve, but I can't understand why you insist on using terms that focus on human societal issues and then conflate them with biology [i.e. cooperation within a ruler and subjects].  Even within that context, human society is fully cooperative, but it has little to do with broader biological principles.

    You point regarding "exploitation" was "wrong" because you keep insisting on putting it into human social terms.  It isn't intended as an argument where someone can rationalize exploiting another individual.  There's no biological basis for that; it is a pure social construct.

    Similarly, I don't know why you feel compelled to bring up "free will".  The acquisition of energy and external resources has little to do with volition.  You don't consciously have to breathe any more than you consciously control your digestion.  Why you think that "will" [free or otherwise] has anything to do with this, escapes me.

    Mundus vult decipi
    Steve Davis
    Blue-green, thanks for finally treating the matter seriously.
    Now for a look at your logic.
    " living things do not need “external inputs for initiation and for sourcing of energy” …. (for) they are independent and spontaneous. (According to Steve.)
    Wrong.
    The living things are not independent, the cooperation is independent. You've confused the concept with the entity, a common mistake.
    "That sounds like they EXPLOIT their environment, but I'm mistaken."
    That was an unfortunate choice of words by Gerhard, he used it in the sense of "use their environment" which is acceptable, you are putting a selfish slant on it, which is not acceptable.
    "Bringing opposites like cooperation and spontaneity and independence in a definition is a good way to cover all the bases."
    I think the definition does cover all the bases, but not for the reason you give, as your reasoning is confused. Yes, independence can be seen as the opposite to cooperation, but that is because independence is a noun, while I use "independent" as an adjective of cooperation, which is perfectly acceptable.
    "For each of Steve's three founding attributes for life, their opposites are also symptomatic of life, individually and all together."
    The mistake you make here is that you have attempted, in true individualist style, to reduce the issue beyond the point where analysis is useful. The three words are not single units as you would have us believe. They are grouped together to complement each other, to give the definition clarity, to promote understanding. But when clarity comes up against ideology, ideology wins every time.
    Gerhard Adam
    I think the term "exploit" is being misinterpreted from my intention.  I'm not using some exotic definition, but I'm also not using it within the negative context of human social interactions.

    For example, we know that wood burns through oxidation producing a fire.  By itself, this is simply a chemical reaction that, left to itself, will simply continue until one of the required resources is exhausted.  However, we can "exploit" fire for light and heat.  The distinction here is that we are "using" these traits for a specific purpose, whereas fire has no "intent" to produce light and heat.

    Part of the reason for this distinction is that if we consider wood burning, then technically one could argue that the process of oxidation is "using" the wood as a fuel.  However, it is not "exploiting" any particular trait of the wood for some other purpose, it is simply an uncontrolled chemical reaction that will run until the wood fuel is depleted.  On the other hand, organisms can "exploit" the wood for shelter, fuel, food, etc.  In short, living organisms "exploit" the wood's traits for their own purposes. 

    Definition:
    exploitMake full use of and derive benefit from (a resource)

    In this context, it becomes easier to see why burning wood for light and heat is "exploiting" it, rather than simply "using" it.  The operative concept here is "benefit".


    Mundus vult decipi
    blue-green

    Steve, you are naturally fond of your own creation. Being protective of one's creation is a hallmark of life…. I can't fault you for that.

    When such behavior is excessive, it's narcissism. If your irrefutable creation doesn't seem fragile, see how it fairs after it leaves your bosom and travels far in the world. Time dampens most enthusiasms. As for your mastery of logic, there's another cautionary tale:

    "Logic is like the sword— those who appeal to it, shall perish by it."

    Samuel Butler (1835–1902)

    Thanks for addressing how your touchstone sheds light on the existence of free-will.
    What else can you do with it?

    By cautionary tales, I mean cautionary for us lesser mortals. I have already been skewered by my logic and your three-fold triangle of complementaries. Your fruit is over my head.

    Steve Davis

    "Steve, you are naturally fond of your own creation. Being protective of one's creation is a hallmark of life…When such behavior is excessive, it's narcissism."
    Nothing could be further from the truth.
    I would be absolutely delighted if you or anyone else could come up with a better definition. My concern is knowledge, not self-promotion.
    "Time dampens most enthusiasms."
    Well, my definition has been out there for three years now, but no serious refutation has been attempted. That does not mean it's untouchable, but it does mean it has substance.
    "Logic is like the sword— those who appeal to it, shall perish by it."
    What does that mean? That logic is dangerous?
    "Thanks for addressing how your touchstone sheds light on the existence of free-will.
    What else can you do with it?"
    Free-will is not relevant to a definition of life.

    Thor Russell
    OK I can't pass up that kind of a challenge ...Firstly what do you classify as life? Presumably a prion isn't, a cellular virus is, what about a computer virus that can modify its own code? 
    Its not known how life began, but a definition of life must give sensible answers to different proposed processes. One I personally find interesting (compared to the replicator starting first) is that the boundary came first "closed, membrane vesicles" as they are called.

    I can't remember the steps in detail unfortunately but lets go with what i have, and you tell me exactly when chemistry becomes life.
    1. The vesicles are essentially stable bubbles, made up of a phospholipid bilayer. These can form naturally, grow naturally in the right environment divide into two because of surface tension effects I think. Now as I said I don't think it makes sense to make a binary on/off decision about what is life, because unless it starts suddenly it makes sense to describe the steps in terms of a progression. I would not call these vesicles alive, but label them as the beginning of a potential process from which it could start.

    2. Vesicles that are porous enough to let long thin molecules through are more successful than those that don't, because those molecules clump together when inside to give structure. These vesicles out-compete the other type. Alive or not?

    3. Sometimes crystal-like molecules that can grow by themselves are assimilated into the vesicle. These provide more consistent structure than just random molecules. Vesicles that let these ones through specifically are more successful than those that just let anything through. The crystals and vesicles are now dependent on each other for their successful proliferation. This is looking a lot like "independent spontaneous cooperation" now isn't it? Surely if you insist on this definition and a binary yes/no for life then this system is now alive. 

    However the system described is also clearly less life-like than a complete living cell with DNA. I argue that a clear yes/no answer for what is life is not possible or desirable and that your particular definition while definitely useful and thought provoking does not always give the correct answer.






    Thor Russell
    Gerhard Adam
    ...a complete living cell with DNA.
    Well, that's kind of extreme, since it isn't likely that DNA was even a factor during the origin of life.

    Your examples need answer only one question.  Do they exploit the environment to their own ends, or simply interact until resources are exhausted?  Despite the awkwardness of the terminology, life displays a "purpose" that a chemical reaction lacks.

    NOTE:  I am not ascribing a mystical, magical, or any kind of exotic meaning to "purpose" here beyond using the word to indicate that life directs its "exploits" towards its own survival.  Therefore "purpose" or "intent" are used to describe life's activities [i.e. when a cell divides, it would be hard to argue that it didn't "intend" to divide]. 
    Mundus vult decipi
    Steve Davis
    Thor, thanks for your thoughts.
    "Presumably a prion isn't, a cellular virus is, what about a computer virus that can modify its own code?"
    A virus is almost alive in the sense that it takes over the cooperative aspects of host cells. (See below) A computer virus is not alive because it did not arise independently.
     "This is looking a lot like "independent spontaneous cooperation" now isn't it?"
    It's getting close, but the cooperation bit is not clear. Dependency is not necessarily cooperation.
    "...your particular definition while definitely useful and thought provoking does not always give the correct answer."
    Why or where does it not give the correct answer?
    There will always be debate about the point where cooperation begins. But there should not be.
     If the constituent parts of the entity perform functions that contribute to the success of the entity then that is cooperation. A virus therefore, becomes a constituent part of a new entity that has a new measure of success.
    Thor Russell
    To me your definition gave the wrong answer in situation 3, however that depends on the definition of cooperation as you point out. Mine was different from yours apparently. I think that you would need to define cooperation more explicitly so as to avoid misinterpretation etc. I personally am not sure that trying to define life in so few words is possible without misinterpretation. Any short definition is going to need to be explained and expanded upon.To me your definition is interesting because it appears quite different to the others and I originally assumed it wouldn't work. 
    However I still stand by my claim that any sensible discussion on what life is should discuss various stages of things on the way to life. Personally I think that this would make it seem less magical. The question "how can life come from non-life?" must involve stages so why not introduce them from the start?
    Thor Russell
    Steve Davis
    "I think that you would need to define cooperation more explicitly so as to avoid misinterpretation etc." But what could be clearer than the parts of the entity performing functions that contribute to the success of the entity? If your idea of cooperation is different or better then please let us know. "However I still stand by my claim that any sensible discussion on what life is should discuss various stages of things on the way to life. Personally I think that this would make it seem less magical. The question "how can life come from non-life?" must involve stages so why not introduce them from the start?" But that's part of the problem Thor. People are obsessing about this to the point where they cannot focus on what life actually is. The origin of life and the definition of life are separate questions.
    Thor Russell
    I clearly have a different definition of cooperation to you, that leads me to classify 3. as life. Even if this is the "wrong" definition if enough people have it, then clarification of "cooperation" would be useful for people seeing your definition.
    Thor Russell
    Steve Davis
    So clarify it Thor. What is your definition of cooperation?
    Thor Russell
    Well this is Wikipedia:"Cooperation or co-operation is the process of working or acting together. In its simplest form it involves things working in harmony, side by side, while in its more complicated forms, it can involve something as complex as the inner workings of a human being or even the social patterns of a nation. It is the alternative to working separately in competition. Cooperation can also be accomplished by computers, which can handle shared resources simultaneously, while sharing processor time."


    The stage of life described in step 3 fits "In its simplest form it involves things working in harmony, side by side," The crystals and vesicules clearly are working in harmony, they are furthering each others existence. 
    Thor Russell
    Steve Davis
    Thor, if you're happy to consider a crystal to be working, that's fine, although I would probably not go quite that far. And it's possibly a situation like the one you describe that could have been a stage in life developing originally. But that's not of great importance to this discussion, however, I think we have a workable theory of life to apply to any alien life possibilities that might eventuate. We have a definition that has practical benefit.
    Gerhard Adam
    Vesicles that let these ones through specifically are more successful than those that just let anything through.
    Perhaps another element that is missing is the definition of "successful" in this context.
    Mundus vult decipi
    The MatrixDNA

    Hi…, Steve,

    My best workable definition for life in three words would be: self-reproductive opened systems.

    If you don’t know it, there is a new paper about “cooperation” here:

    Could simple anger have taught people to cooperate?

    World Science

    http://www.world-science.net/exclusives/110620_cooperation.htm

    You will say that is not cooperation for defining life, but about human social behavior. I think that it is a deterministic evolutionary result from primordial mechanism of cooperation, so, if the social is ruled by mechanisms/process of Nature, the social is a source for learning about natural cooperation.

    The very fact that the authors found cooperation coming from anger is a strong evidence of (a still Matrix/DNA theory) a mechanism in Nature:

    1) An ordered super-specialized system (like dinosaurs, solar system, etc.) reaches its limitations, cannot absorbs more informations from the environment for continuing self-evolution;

    2) the system is attacked by entropy from the environment, which causes degeneration, which means a collapse in time/space,cleaning the last erroneous informations added by the system searching its thermodynamic equilibrium and closing doors to evolution ( example: a)evolution discards dinosaurs and go back to small reptile like cyanodonts. From here evolution built the mammals apparatus and continued ahead; a) evolution discards astronomical systems and go back to microscope world lifting organic matter, molecules, cell systems);

    3) Entropy causes the fragmentation of a super-specialized system into its bits-information (genes). The collapse makes that these bits are inserted towards the past and inner center of the specie (example: activation of inactive genes of cyanodont inside the reptile specie, stellar radiation emitting the fragments of whole astronomical systems towards planets’ surfaces, etc.):

    4) Fragmentation into bits and orientation for them to meet at a same point of time/space causes chaos at an ordered environment. The bits are under chaos and conflicting among themselves;

    5) The chaos state produced by the war among bits threats the bits to death. Weakened they learn stopping conflicts and how to cooperate;

    6) Cooperation brings order, order brings grow and equilibrium, absorption of informations from the environment;

    7) The species goes against evolution towards thermodynamic equilibrium, absorbs the wrong informations, super-specializing in a way of life;

    8) Nature discards the species and goes back in time and space of the species for beginning again by a new way…chaos again.

    Them, as you can see in that paper, social human behavior makes that cooperation is the next step from states of anger among the bits ( I mean, among the individuals). It’s the same universal law that Nature apply over any natural system, from atoms, to astronomical, to biological shapes of natural systems. So, in my theory, cooperation does exists, but is only a phase  of a complex process. What do you think?   

    Steve Davis
    Hello again Louis.
    I'm sure that anger can be useful in starting the cooperation process, as can fear. But these are behaviours that develop long after the development of life itself.
    As I pointed out in a few of my earlier articles, the molecular level cooperation that began the life process existed prior to evolution beginning, because there had to be life before there could be evolution.
    Other forms of cooperation can come into being through evolution itself, and then evolve further, which is why cooperation is a complex concept.
    The authors of the article you linked us to, along with almost everyone else who has an opinion on this subject, somehow fail to realise that cooperation preceded evolution.
    Thor Russell
    The first problem is that well informed people can have genuienly different ideas of what the word means. Their ideas could be self-consistent and just as valid as each other. In that case when discussing it, it makes sense to just define it first.
    The second is that just like how you can never say exactly when one species becomes two (e.g. a parents offspring would have to be a different species to it) you can never say exactly when non-life becomes life. If you were to have watched life start on earth, you would see a process that became more and more "life-like" and would have to just make an arbitrary distinction about when "life" started. You could definitely label each step, but giving an arbitrary not life/life distinction wouldn't be meaningful.


    In order to refute someone elses definition you would need to show that it would mis-classify something clearly agreed upon e.g. classify fire as life. Of course the shorter a definition the less precise. For "self-reproduction with variations" you need to define "variations" and at what stage something varies to the point where it is no longer self. You could even read that definition to be self-contradictory as "variation" no longer means "self".
    Thor Russell
    Hi Thor, you certainly sound like a more careful thinker. I have just developed a theory and it turns out it is the whole truth about all life and cellular life. I have developed a language of understanding that is infallable. Universal truth about any life form. Take a look and you WILL find Ultimate truth in it and explanation of the nature of existence. It affirms that cellular life form is possible elsewhere in the Universe. My blog: https://ciscosphere.wordpress.com/category/uncategorized/
    You have to catch up with Nassim Haramein's work sometime. He predicted that someone (me) would come along and have a simplified explanation for all the phenomena humans have observed and knowledge we have accumulated and the theories or laws he presented, in all of history. The closest I have found so far in explaining what I have, is these guys: http://quod.lib.umich.edu/cgi/t/text/text-idx?c=ptb;idno=6959004.0003.00...
    Just remember this: "Intelligence recognizes what has happened. Genius recognizes what will happen." -John Ciardi
    Nassim is a genius, he predicted that someone would come along with a simpler explanation for everything in the universe, in an interview by Coast2Coast radio. Nassim's site:. theresonanceproject.org

    Steve Davis
    Francisco, you have not come up with a definition of life.
    You have developed a theory about the conditions necessary for life to develop anywhere in the universe. That may well be useful, but it is not a definition of life.
    The MatrixDNA

    Hi, Francisco… Life is pressure towards cooperation?

    Thanks for mentioning my name at your blog.Since I gave the idea for you writing a book about “pressure” I must advise youthat is not easy. Before doing that, I think, you must now going down to details in Nature, looking for scientific data, and arresting those that are evidences for your theory. You need transforming a theory designed in language into a sequence of real data. I will follow you, in your progress, because your data help me developing my theory and is a good job for human kind evolution of knowledge. You have an insight, explore it.  

    Your basics are “pressures”. Ok, life is result from pressure, but where come from this pressure? Where was pressure at the Big Bang? How it was present in the whole universal evolutionary History? Pressure could be a hidden purpose in Nature? From who, what?

    Look to the description of a process where pressure is seeing as unavoidable, a force of evolution acting over established natural systems, in my post-reply to Steve, but remember, it is only theory. In this process, pressure upon a system is created by the system itself. It seems that life is a process of self-correction, self punishment, for going back into synchronization with Nature. Like we now need change our behavior for avoid climate changes.

    You say in your theory:  “Manifestations are manifested forms of manifestations of Pressure.” If you don’t go further defining pressure, this will be seeing as circular reasoning. I have a suggestion: remember that the relationships between hardware and software in computer science history are all about pressure, feed-back of pressures. The development of a new hardware abilities man for getting more new informations; those new informations are pressures, while processed in the mind of man, which was the creator of the primordial software; this processing makes that the mind develops a new imaginative software, but the currently hardware cannot process it; than, the new imagined software makes pressures over the hardware, asking for new tools. And so on. It is just this process of feed-back that I  found explaining evolutionary Universal History and if you see my website, you will see the research about this field. Where was “manifestation” at the Big Bang? My suggestion: two vortices, opposites spins, created the primordial chaos; the chaos weakened the two vortices, the chaos and the universe became cold, which permitted the fusion of those vortices by self-cooperation. The fusion was the first event of manifestation, creating matter. What do you think?
    What actually is the point in defining something which we know exists, we know operates as a thoroughly interdependent system and which has a perfectly good name in English and most other natural languages?  If my six-year-old nephew says "What's that bird?" and I say "It's a robin", I don't then go away and define the word "robin", it's just a label. In fact if I did define it, it would lose its usefulness. So why the urgency to define "life"? It's not as if we have thousands of possible candidates and need to decide which ones are alive and which ones are not. Even borderline cases like viruses and prions are so obviously part of the same life system that it makes no difference what we call them. But suppose we define life based on our limited experience and something turns up which is intelligent but doesn't, for example, reproduce. Will any decision whatsoever depend on whether we defined life to include the ability to replicate? God help us if we act on limited definitions, I would have thought the utter disgrace of hunting aboriginals for sport would have taught us a lesson but maybe that's the point. Let's define life as narrowly as possible then we can rape, pillage and destroy in the way the human race has always done.
     
    Oh and please spare a thought for conscious computers too. They have rights.
    Gerhard Adam
    Actually the point is to avoid the problems you've mentioned.  That's why trying to be as general as possible might provide a generic enough criteria so that life that is significantly different won't be ignored or overlooked.

    This is why I opted for exploitation, because if we were to see something in the environment that seemed unusual or out of place, it might just be the byproduct of some life-form which hasn't been located or identified yet.  That certainly doesn't mean that the presence of life would necessarily leave a trace, but but it seems unlikely that such environmental modifications that we associate with life would exist without some life-form [even an extinct one] having been present.
    Mundus vult decipi
    Steve Davis
    "That's why trying to be as general as possible might provide a generic enough criteria so that life that is significantly different won't be ignored or overlooked." Exactly so, Gerhard.

    "But suppose we define life based on our limited experience and something turns up which is intelligent but doesn't, for example, reproduce."
     Derek, that's the beauty of the independent cooperation view of life, and the exploitation or use view. It's hard to envisage mistakes and poor judgements of the kind you fear, flowing from such generalised definitions.
    Some people (who are not giving enough thought to the matter) are hung up on things such as reproduction, failing to realise that reproduction is a function of a living organism as we currently know it. It has nothing to do with a definition of life. Life and organism are different concepts. 
    blue-green

    Exploitations on human scales are easy to spot. Have you glimpsed the Alaskan Gold Rush Mining series on the Discovery channel? What a tale of misery and irrational exploitation it is …. as they strip down precious riparian environments to find less gold (even at $1500/oz) than what they consume in operating costs.

    How can one be sure of the presence of life ~ from astronomic distances ~ on a celestial body?

    Long before nuclear weapons flashed and Earth was scarred by mankind, how would one know for sure ~ from a great distance ~ that life is (or was) teaming on the earth? What are the best tools to use,  short of sending a probe down for a really close look? How might one distinguish the electro-chemical signatures of volcanism, for instance, from those of living processes?

    ................

    The philosophical argumentation here can be entertaining, yet seriously, would anyone take their car in for repair to a shop run by Francisco 'n Louis? Would you entrust the care of your body to the Davis Health Clinic or Ed's Repro Services?

    (The latter is in honor of Edward Trifonov of self-reproduction fame with variations.)

    Gerhard Adam
    How can one be sure of the presence of life ~ from astronomic distances ~ on a celestial body?
    This probably wouldn't be possible unless life was quite prevalent on the planet.  On the early Earth, such a situation was seen in the production of oxygen as a byproduct of existing life.

    Obviously the larger the life forms that exist, the more readily one can observe environmental modification whether it be from something like an ant hill to a beaver dam.  However, for microscopic life, it seems most likely that we would be looking for an unusual chemical signature suggesting that there were some chemical byproducts present that would be unexpected.
    Mundus vult decipi
    MikeCrow
    Free oxygen is the signature of life on earth. From what I've read, if there was no life liberating free oxygen, it would all end up bound with other chemicals. If life stops liberating Oxygen, it'll vanish.

    As for Gold Rush, in a few decades (after they leave) the only thing you'll find there other than vegetation will be any equipment they leave behind, and that will melt away in a few 10's of decades(at most), and if(when) glaciers make it that far nothing they do will matter at all, it'll all be ground away.
    Never is a long time.
    Free oxygen is the signature of life on earth.
    The prevailing view is that early life was anaerobic. Oxygen would have been extremely toxic. A waste product from photosynthesis with the added advantage of killing off any neighbours who might be intent on eating you. In fact it still is an extremely dangerous chemical and has to be kept out of the inner workings of the cell - which are generally thought to be closer to the earliest life forms. Of course oxygen in the air made predation a viable way of life as you only had to eat your neighbour and then use their waste oxygen to metabolise their body tissues. Serves them right for polluting the planet - surely it was obvious that sooner or later so-called "animal" life would develop and plants would be left practically defenceless? 
     

    MikeCrow
    The prevailing view is that early life was anaerobic.

    True, and I skipped right over that period. Which might be very hard to detect from long distance. But my point still applies after oxygen generating life exists.
    Never is a long time.
    Big assumption. It just happens that sunlight on the earth has enough energy to split off oxygen from water so there was an opportunity for plants to exploit it, though they took umm, well, a very long time, to get round to it. Life managed perfectly well on other forms of chemical energy before that so there's no reason to assume that the invention of photosynthesis is ubiquitous. Did you ever read Asimov's _Goose that Laid the Golden Egg_ ? :)