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Working towards a definition that shows no circular reasoning[edit]

Dear editors of Wikipedia, after working more than 20 years now on this subject I like to point at an aspect of the Wikipedia definition of life which may well require your attention. It concerns a circularity in the separate definitions of what is life (In Wikipedia: "Any contiguous living system is called an organism") and what is an organism (In Wikipedia: "an organism is any contiguous living system"). From a philosophical point of view, circularity is considered as to be highly undesirable when constructing definitions. As an example of how a definition can be anchored and the circular reasonign may be solved, I invite you to find inspiration on the following page of my website:

One of the interesting aspects of a definition of life is that organisms are only living beings when they show physical activity, but not when they are for example Jager008 (talk) 14:36, 24 July 2013 (UTC)frozen. When they are frozen they are still organisms, but no longer living beings (because they have stopped living). Accordingly, it is necessary to first define organisms, then te define living being (an active organism) and finally to define life as an abstract group-property of organisms.

Contrary to opinions which are broadly held by the public, the following properties do not define life, as can be demonstrated by means of simple test cases:

1. An organism can show the property of life even when it does NOT show reproduction (there exist many organisms which are alive but fail to reproduce)

2. An organism can show the property of life even when it does NOT show metabolism (frozen and dried organisms are still organisms when they are frozen or dried). A frozen organism does not show the property of 'living' though.

3. An organism can show the property of life even when it does NOT show signalling functions or mobility or the like (frozen organisms don't show dynamic aspects at all). Signalling and other dynamic functions are indications of the concept of 'living', which differs from the concept of 'life'.

I think it would be a challanging undertaking if Wikipedia would test its own definition agains such litmus test examples.

As a definition which has no problems with a broad range of test cases, I can suggest the following (page 94 of The Pursuit of Complexity):

'All 'operators' at least as complex as the cell are organisms' (this preparatory sentence is required to define the concept of organism, all the different operators are: the quark, the hadron, the atom, the molecule, the cell, the endosymbiont cell, the cellular and endosymbiont multicellular, and the organism with neural network).

Now we can define life as:

'Life is a general term for the presence of the typical closures found in organisms' (the typical closures are e.g. a memebrane and an autocatalytic set in the cell).

With the above I hope to have supported your valuable work.

Kind regards, dr. mult. Gerard Jagers op Akkerhuis 14:31, 24 July 2013 (UTC)Jager008 (talk) 14:36, 24 July 2013 (UTC)[1] — Preceding unsigned comment added by (talk) 14:45, 23 July 2013 (UTC)


Crafting a definition to incorporate frozen organisms seems too much. Frozen organisms, although non-metabolizing, have the potential to be viable if thawed. Any way, if your living system definition ("Life is a general term for the presence of the typical closures (e.g. a memebrane and an autocatalytic set in the cell) found in organisms".)) was published in a peer-reviewed journal I think we could include it. BatteryIncluded (talk) 14:57, 14 August 2013 (UTC)

Dear editors at Wikipedia, upon visiting this talk page again after quite a while, I appreciate that you ask for references that can support my above suggestion for a definition of life. In this respect, I can contribute in the following way. A first reference is my book "The pursuit of complexity" (reviewed by 20 colleques, KNNV Publishing, Zeist, The Netherlands, 2012) where I discuss the definition of life in three steps, on pages 27-29, pages 87-88 and pages 94-96. If I restate the definition on page 94 the abstract concept of life can be defined in two sentences as follows: First on has to define what is an 'organism'. This is possible by invoking the complexity ladder of the operator theory, and defining an organism as "any system with an organisation that complies with an operator type that is at least as complex as the cell (as an operator type)". As part of the operator hierarchy, every type of operator is defined by type-specific closures. Now that we have defined the organism, we can say that "life is a general term for the presence of the closure found in organisms". If the closure is lost a system is neiter an operator anymore, nor an organism. An organism is living, if it is dynamically activy. If it is not active, it can still represent life (not 'be' life!) as long as its closures are intact. This approach to defining life has also been published in the following studies:

1. Towards a hierarchical definition of life, the organism, and death. Jagers op Akkerhuis G.A.J.M. (2010). Foundations of Science 15: 245-262.

2. Explaining the origin of life is not enough for a definition of life. Jagers op Akkerhuis G.A.J.M. (2010). Foundations of Science 16: 327-329.

3. The Role of Logic and Insight in the Search for a Definition of Life. Jagers op Akkerhuis G.A.J.M. (2012). J. Biomol Struct Dyn 29(4), 619-620 (2012).

4. Contributions of the Operator Hierarchy to the field of biologically driven mathematics and computation. Jagers op Akkerhuis G.A.J.M. (2012). In: Integral Biomathics: Tracing the Road to Reality.

Additional information can be found at:

By the way, in so far as life is an abstract concept, it can only refer to a state of matter, no 'be' a state of matter ;-) Meanwhile, the operator based definition indicates WHAT states of matter comply with the abstraction of life: namely the states which comply with the organisation of the different operator types, from the cell and up.

I hope to have contributed to your noble work. Regards, Gerard Jagers op Akkerhuis Jager008 (talk) 11:59, 20 March 2014 (UTC)

G. Jagers, I included the two key sentences you indicate and the references you supplied. Please review it for accuracy. Thank you, BatteryIncluded (talk) 16:26, 26 July 2014 (UTC)


Dear Batteryincluded, I have much appreciated your actions. The present text can be a start of a fundamental contribution to the definition of life topic on Wikipedia (including the definition of what is an organism). Although the present text gives an impression, I would like to suggest to you the following lines as a slightly more inclusive and precise phrasing:

The present alinea reads: "Another systemic definition, called the Operator theory, proposes that 'life is a general term for the presence of the typical closures found in organisms; the typical closures are a membrane and an autocatalytic set in the cell',[76] and also proposes that an organism is 'any system with an organisation that complies with an operator type that is at least as complex as the cell.[77][78][79][80] Life can also be modeled as a network of inferior negative feedbacks of regulatory mechanisms subordinated to a superior positive feedback formed by the potential of expansion and reproduction.[81]"

My suggestion for a slightly altered text would be: "Another definition of life is based on a novel axiomatic systems theory called the Operator Theory. This definition of life is based on a ranking of object types from fundamental particles to organisms with brains. Real world objects corresponding with these types are called ‘operators’. Every next operator type is based on the combination of a new kind of structural and functional closure, which together are named the ‘typical closure’. For example, the typical closure of a bacterium combines the membrane (structural) and the autocatalytic set (functional) [76]. And the typical closure of a multicellular organism combines the cell membrane that is not shared by adjoining cells (structural) and plasma strands between cells (functional)[76]. 'Life’ can now be described as ‘a general term for the presence of the typical closures found in organisms’. The question of what is an organism can be answered by stating that an organism is 'a system with an organisation that complies with an operator type that is at least as complex as the cell’.[77][78][79][80] If an organism loses its typical closure, it is no longer on organism, it is no longer an operator, and it no longer represents life: it has ‘died’.

(the following sentence does not link to the operator theory based approach, so I suggest that it is kept separate). Life can also be modeled as a network of inferior negative feedbacks of regulatory mechanisms subordinated to a superior positive feedback formed by the potential of expansion and reproduction.[81]

If you think that some discussion is required of the above, please feel free to contact me outside this forum (gerard.jagers ad Do you think it may be insightfull to offer the readers of Wikipedia some basic information about the operator theory?

Kind regards, (talk) 11:40, 30 July 2014 (UTC) Gerard Jagers

Consciousness of matter[edit]

"Life is a State of Matter", Sekhar, DMR., Life as a State of Matter, In the proceedings of, 1st International Conference “Life Energy, Syntropy and Resonance”, World Institute of Scientific Exploration – Viterbo, Italy, August 1- 4, 2013,

DMR Sekhar (talk) 09:31, 14 August 2013 (UTC)

X mark.svg Not done - Hello Sekhar. I looked at your paper but stopped short at the intro. How do you know an amoeba or a tomato has "consciousness"? Can't use that as a factor to define life or determine if an object is alive. BatteryIncluded (talk) 14:38, 14 August 2013 (UTC)

Dear Sir, I just saw your comment here. Sir, kindly read fully and then reject. Please see these two blogs too. and DMR Sekhar (talk) 16:51, 25 July 2014 (UTC)

I read it fully and still reject it. First: It is an original idea (WP:OR) that has not been peer-reviewed by any scientific journal. Second: it is deeply flawed because your model hinges on the fringe unscientific assumption that a single DNA molecule has "consciousness". Your assay may not be circular reasoning, but is a downward spiral because it is self limited with anthropocentrism. A DNA molecule is a chemical code or blueprint, not an entity with consciousness! A code ≠ consciousness, whether chemical, written or digital. Yes DNA interacts with many other molecules but it is not because it has consciousness, or because it has the "will and purpose" to do it, but because of the natural intermolecular forces such as electrostatic, hydrogen bonding, ionic bonding, covalent bonds, van der Waals force, etc. The current scientific understanding of life is descriptive; life is a process, not a substance. Cheers, BatteryIncluded (talk) 17:24, 28 July 2014 (UTC)

Well BatteryIncluded, I said that life is a state of matter and not life is a substance. If life is a process then there should be a potential that drives the process. Is it not? request to see this link: Thanks, DMR Sekhar DMR Sekhar (talk) 13:42, 9 December 2014 (UTC)

Rewrite This Article[edit]

The Life entry is need of a lot of work. It has a lot of unnecessary statements or at a minimum statements which don't read well in their current placement / context. Here are a few small examples.

This should be at the top of the article. It is a challenge for scientists and philosophers to define life in unequivocal terms.[25][26][27] This is difficult partly because life is a process, not a pure substance.[28][29] Any definition must be sufficiently broad to encompass all life with which we are familiar, and must be sufficiently general to include life that may be fundamentally different from life on Earth.[30][31][32]

This doesn't read well, and feels like it was tossed in. Life can survive and thrive in a wide range of conditions. — Preceding unsigned comment added by ClearConcise (talkcontribs) 18:50, 25 December 2013 (UTC)

Hello. Your request is not clear to me. You want to place that statement at the top, yet you claim "This doesn't read well and was tossed in". --BatteryIncluded (talk) 14:20, 20 March 2014 (UTC)

Grammatical Edit[edit]

In the opening paragraph, the last sentence currently reads, "Biology is science concerned with the study of life."

I think this should be changed to read, "Biology is the science concerned with the study of life."

It would just be the addition of "the" in between the words "is" and "science".

JSimar (talk) 01:31, 25 June 2014 (UTC)JSimar

Yes check.svg Done, Thank you. BatteryIncluded (talk) 20:08, 28 July 2014 (UTC)

Earliest known evidence for life? - as of June 25, 2014[edit]

On the site is an article claiming problems with the earliest evidence from the Archean (3.5 bya) and concludes that it is abiogenic. It also references a 2004 article from Science (magazine) in which these are argued to be "Earth's oldest trace fossil". (which is prior to the two studies given in wikipedia, but never-the-less should have some bearing on the acceptance of these studies.) So, I am wondering how well accepted are the claims made in this article that graphite and microbial mat evidence indicate life existed at 3.48 - 3.7 bya? Specifically the author of the critical study states:"..the oldest bona fide candidate trace fossil comes from 1.7 billion year old rocks in China.." The difference between 1.7 and 3.7 billion years before present seems too enormous to ignore. My best guess to reconcile the Wikipedia view with this author's EXPERT statement is that the graphite & mat evidence is NOT generally accepted. This is in stark contrast to the absolute statement of fact that "The earliest life on Earth existed at least 3.5 billion years ago..." [Which seems to me such a religious and unscientific a statement as to invalidate its inclusion in a scientific discussion. NO qualifications? For Shame! That is NOT EVER what Science claims! (Science ALWAYS bases her claims ON THE AVAILABLE EVIDENCE!! (not some absolute concept of "truth")] — Preceding unsigned comment added by (talk) 17:56, 25 June 2014 (UTC)

I sugggest removing this stupid reference to Sharovs non-peer reviewd and peer rejected papers, see: For the reasons whyBicelPhD (talk) 11:51, 14 August 2014 (UTC)

Semi-protected edit request on 15 July 2014[edit]

Add the word organic as indicated in the following sentence, the first in the article: "Life is a characteristic distinguishing organic physical entities"

Paradigmatic Autodidact (talk) 04:20, 15 July 2014 (UTC) The reason for my request should be self-evident.

It's not self-evident to me. It just so happens that all life we know about is organic, but I've never heard it suggested that being carbon-based is a fundamental requirement for life. Life that is not carbon based has been widely speculated about (see Hypothetical types of biochemistry#Non-carbon-based biochemistries). The cited sources also say nothing about being organic as a requirement. Adrian J. Hunter(talkcontribs) 04:37, 17 July 2014 (UTC)

An organism is an contiguous living system?[edit]

Living system is ambiguous. Defining something in terms of something not well defined in science is philosophy not empiricism, especially as no citation is given. Organisms can be well defined with respect to cell theory: they are the units of life and can be either single-celled or multi-cellular. Mrdthree (talk) 10:40, 10 August 2014 (UTC)

I agree. The word "contiguous" is horrible here. First, it's most common meaning is 'touching' or 'adjacent to'. Second, it has zero pedagogical value: unless you already know what is meant, it conveys nothing.Abitslow (talk) 19:20, 2 January 2015 (UTC)

Semi-protected edit request on 11 December 2014[edit]

' Life is meant to be enjoyed and not wasted. If you only care about how much money you are making they you're not living, you are only existing. To exist is never enough because it just means you have life but you do not live it. People pay way to much attention to the little things, like Eric B & Rakim said Don't Sweat The Technique. People need to stop letting other people run their lives for them. Do whatever makes you happy and also whatever you want (as long as it's legal) then go for it. Staying in the herd of society is not a good way to say that you live. Stand out, stand up, and dont be afraid to be an individual in the sea of exsisters. (talk) 13:40, 11 December 2014 (UTC)

X mark.svg Not done: you have not made clear whether this is something you want added to the article or something else. Please restate the request in terms of "change X to Y" or "add X" and reset the request template. G S Palmer (talkcontribs) 13:50, 11 December 2014 (UTC)

Lede needs work.[edit]

I have a number of problems with the lede. "Life is a characteristic..." OK, I don't know a better way to put it; EXCEPT that it fails to convey the 'truth' that the given definition is one of many possible (and possibly contradictory) ones. That is, it implies a clarity and certainty that isn't actually present in the science. A simple statement that there is no one definition that all (relevant) scientists accept should be included, imho. "The smallest contiguous unit..." what garbage! On the table to the right both viruses and viroids are listed, neither of which are cellular!! It IS important that some experts do NOT consider them to be 'life' while others do, and it should be in the lede! "...respond to stimuli.." is MORE garbage! A rock reponds to stimuli, air responds to stimuli; this is completely devoid of any clear meaning. "...and, through evolution, adapt..." So suddenly we are talking about species rather than individual 'organisms'??? If I build an organism which self-replicates exactly (doesn't evolve), is it or isn't it 'life'? How about me? I neither evolve nor do I self-replicate (and my homeostasis is questionable). What rubbish. Look, you have to decide whether in any given paragraph you are talking about species (across multiple generations) or individuals. You have to keep the difference in defining characteristics clear or you'll spout nonsense like the above. "A diverse array of living organisms can be found in the biosphere of Earth, and the properties common to these organisms..." What hot air! What bloviation! WHO needs to be told that life on Earth is 'diverse'? (And if they exist, how does this sentence help them? - WTF is a 'diverse array'???) I want to strongly object to "the properties common to these...carbon and water based, cellular, complex organization, heritable genetics." What does carbon and water based mean? a slurry of diamonds? Again, someone has confused structural basis (organic carbon) with the necessary environment (availability of liquid water). Life exists IN THE PRESENCE of water, life IS organic carbon based. Second, wtf does 'complex organization' mean? (for instance, does the Sun have a 'complex organization'? How about a computer? Or the internet? How about a transistor? a snowflake? rubbish.) Third, these are NOT "the properties"; these are SOME of 'the' properties! Other problems: No mention is made of the possibility that life began and became extinct multiple times during the Late Heavy Bombardment. I think this is important enough a point to include, since it has implications for ideas of continuity, progress, evolution, and our own existential fragility. Finally, get rid of the silly bloviation on 'the meaning of life'. It belongs soley in the 'see also' section. What a waste of space! "The meaning of life" is almost invariably about consciousness and mortality, not about life as a process.Abitslow (talk) 20:26, 2 January 2015 (UTC)


The introduction currently states:

Life is a characteristic distinguishing physical entities having biological processes (such as signaling and self-sustaining processes) from those that do not

I looked up Biological process and read that these are chenical processes carried out by living things, so is not this a circular definition as chemical processes are ubiquitous. The definition seems to say only that life is that which living things possess.

The examples of processes given in parenthesis seem of a far higher order of complexity than the definition implies would be a base case, like citing an entrepreneur. Signalling is a highly complex set of processes does it apply to single cell organisms for instance? Does self-sustaining process refer to reproduction or to far simpler processes of repeating cycling chemical reactions? What is the difference between a computer using organic components and one that does not?

I'm wandering! The definition says that living entities are those that use chemial reactions that are biological and they are biological if they are being used by living entities. There are more common definitions of life avalable that seem far superior to this particular attempt at reduction e.g

that which is manifested in functions such as metabolism, growth, reproduction, 
and response to stimuli or adaptation to the environment originating from within 
the organism.

LookingGlass (talk) 18:19, 21 March 2015 (UTC)

Hello. Definitions of life are in the section entitled "Definitions". BatteryIncluded (talk) 22:51, 21 March 2015 (UTC)