Life - an Unequivicol Definition

Maybe you ought to try and understand what a tautology is before you accuse some one of creating a tautology.Definitions are not tautologies. Definitions should always be true for the word they are defining. A definition describes the meaning of a word. If the word is readily used in the language then the definition should apply to how that word is used in the language .ie "all known life" Enough ATP to metabolize the synthesis of the enzymes required for the synthesis of the ATP. Definitely more than one molecule. Because there a basically two camps of thought within OOL. One is metabolism first, and the other is genetics first. The RNA world is the genetics first camp. My definition covers both, because both are in all known cellular life. I am amazed that you challenge this as arbitrary. This definition is the furthest thing from arbitrary. So this definition requires the genetic transfer of information from DNA to RNA to proteins to synthesize at a minimum the enzymes necessary to synthesize the ATP necessary to metabolize. Because living things need catalysts to speed up the chemical reactions. In the synthesis of ATP, those catalysts are enzymes. Certainly living things do a whole lot more than this, but this level of complexity is the minimal amount that a cell could be called "living" Au contraire! It is 100% measurable. All facets of the definition. Therefore it is rigorous.

Well not to make a big deal about this, but it is done all the time. There is black paint, and there is white paint. Grey is a mixture of the two. Well No! Either you drastically misunderstand or this is a severe strawman. Let's examine your example.Let's say since black symbolically represents death, that black is dead stuff. Since white is the combo of all colors, let's say that that is life! Anything white is cellular life which is uncontroversial, unequivocal, and meets most if not all of the seven characteristics of life. Now to the naked eye, one cannot differentiate white from grey for about 10% of the gradient on the left side. It all looks white! The same is true for about 10% of the gradient on the right side. That leaves about 80% which is some shade of grey.My definition is on the grey side of white. It is not 100% white, but very close, and within the 10% gradient line as an analogy. It is a minimalist definition of life. So I disagree with your statement that I am denying the "grey gradient" of life. However, I am saying that "white" (10% margin) and Black (10% margin) is not so fuzzy, and it is definable.Now let's look at some examples with the current 7 characteristics of Life that are in most Biology textbooks:1. Homeostasis
2. Metabolism
3. Growth
4. Adaptation
5. Response to stimuli
6. Reproduction
7. Organization / CellularSelf replicating molecules - 2 and 6 and 4?
Fire - 2 and 3 and 4? and 5? and 6?
Crystals - 3 and 6
virions - 7The only reason "life is fuzzy" is because of the equivocal terms used to define it. With my definition, only one of these terms is used in a very specific way. My definition allows all of these characteristics, but requires a certain minimal level of self sustainment which is identifiable in living things. No equivocation needed.My definition does not remove the grey, but it limits what can be identified as white.

Why? They are imagination. They are fiction. What scientific principle requires such an inclusion? And keeping with your example, once the definition no longer works, it must be abandoned or modified. No big deal. "Science" does posit the theory of panspermia though doesn't it. And within that theory, the life that is seeded on this earth is what we currently identify as organic life. No need to deal with fiction or imagination. "science" is about knowing, and we know what life is. Therefore we can define it.

Percy,This just isn't so. Someone asked about a mitochondria. It meets my definition! It's part of endosymbiotic theory. I don't know of any that can survive outside of a cell. But a functioning mitochondria outside of a eukayrotic cell would be alive according to my definition, and I would be quite happy with that.A definition is to create the description that differentiates living organisms from other chemical arrangements. I chose the simplest arrangement that includes the production of metabolic molecules and the production of the enzymes required for their synthesis. A mitochondria's DNA level is much smaller than the entire cell's.You completely ignored my application of virions, fire , crystals, and self-replicating molecules. All of which fall into the grey area somewhere. Call them fuzzy if you want, but the consensus agrees that none of these are alive. So there must be a recognition that there is some minimal level to be called life. You cannot intelligently argue that this minimal requirement doesn't exist long before this discussion began. What you and others are wanting to do is say that life is a continuum from chemicals to life, and that is a faith based premise that I do not accept. It ignores the many things in life that are not chemical. ie organization, architecture or shape, electromagnetic radiation, and gravity. ( none of which are chemical)And finally, any good definition of life must also identify it's opposite (or death). Life is not the continuum. Death is. So I have used the analogy properly. That is of course if you think you can define death for us chemically?

You have claimed this several times now. Admittedly, I am totally unaware of this. Evidence Please! Hopefully papers I can access on the web. Not journalistic articles I hope.

Seems to me that's exactly what a good scientific definition would be Well when you get there, let me know and we can write a paper on it. Why not suppose a planet where water is HeO2? Diamonds are made from lead? we would still call the diamonds and water, right? Do you see any difference in "supposing an imaginary" observation, and real observations? I guess not. So a good definition is based on imaginary observations and a poor definition is based on actual observation? Wait , that's mom calling from Delton-Four, I'll have to call you back. LOL Edited by AlphaOmegakid, : No reason given.

I have no problem with that. Evo theory is a good example of modifying the theory to accommodating evidence. But the observations come first before the modifications.We don't say "on planet XYZ we can imagine organisms that evolve by non-genetic processes" and then accept that into the theory. My definition makes excellent predictions regarding life on other planets. There is no observational reasons to suggest any other form of life. We certainly can imagine all we want to. But that's not "science". It's Pseudo science.All panspermia hypotheses predict life on other planets as being similar to ours. Cellular based with amino acids and living according to my definition. What do you think they are looking for on Mars?...Cellular life or evidence therof.

You said "You're attempting to create a definition where everything is either living or dead with no shades of gray in between."That just isn't so. I clearly identified entities in the grey area. You are just unhappy, because I don't call them alive. If they are not alive, then they are dead. You and RAZD want the grey area to be living. Then you must decide your definition of life and the differentiation between life and death. And both must make sense. No. I said a lot more than that which you ignored. Read it again. You've got to be kidding, Right?Don't you realize that every atom, molecule, and chemical combination has an architecture or shape associated with it? In particular, proteins must be folded to have the right shape to become either cellular tissue or enzymes. you can have misfolded proteins and they won't catalyze anything. They will have the exact same chemistry, but will not form the right tissue or catalyze the chemical reactions they are responsible for. A misfolded protein is usually a disease.Yes, Percy, organization, shape, and or architecture are very important in living things and it is not just chemicals doing their stuff. So you don't think heat and light affect chemical reactions? Would you like to research this a little before I embarrass you? And gravity also?Yes, much of life is chemical, and all of life is physical, but life is more than just chemical processes.Edited by AlphaOmegakid, : No reason given.

Thanks Tany, I agree completely in a biological sense. So when does a virus die? No one is questioning that it is "alive" in the host cell (actually it is the infected cell that is alive). But outside the host, is it alive or dead? As a virion, is it alive, non-living, or dead?And how about self replicating molecules? When are they dead? etc etc.? Or are they ever alive?This is the reason that we need a good unequivocal definition of life. Bingo! By George, me thinks he's got it!Maybe, I was too quick in the semantics by using the term "dead", but you can see that the term non-living is almost a synonym of "dead". I've been trying to semantically identify the so called grey area. "Non-living" is a perfectly good designation as far as my definition is concerned.The best term is abiotic! Abiotic component - WikipediaSo now we (you and I) have clarified the grey area. We have categories:(1) White=Living==>by some unequivocal definition of life
(2) Grey=Abiotic=non-living
(3) Black= DeadWithin this model dead organisms are also abiotic material, but abiotic material that has never been alive is just abiotic material. I think this model works very well within Biology and especially well with my definition of life.The problem I was having was everyone else in this forum was referring to the grey area as "life" (the "grey area of life"). This makes no sense, because every abiotic thing would be on the pathway to life which is obviously false. The reality is that most abiotic things have no chance at life, many are dead, and some have some of the characteristics of living things.Thanks for your post! It was revealing.Now look at your last sentence, and consider a virus. If it is considered alive within the host cell. Then when the cell is destroyed and the virus is released again, then all life functions would be gone. It would be dead. Both abiotic and dead. This makes a lot of sense using this model. So a virus would not be in the grey area at all. It would be black.

OK, then show me the semantics that clarify "alive" and "non-living" or the model of a grey area makes no legitimate scientific sense. There is no grey area unless white and black, which are unequivocal, are defined!So please make sense of this or drop the analogy. Yes, I recognized that. However you were being quite selective in your quoting of my argument. I responded in kind. This post is much more civil! See post 152

I didn't enjoy anything about this post. It is meaningless elephant hurling to the claims you made. You quoted my request.... You have claimed several times now that viruses can self replicate, metabolize and make proteins outside a host cell. I claim your bluffing or sadly misinformed on this. I have asked for supporting evidence to support this claim. You provided a bunch of non-relevant material.I will give you the benefit of a doubt. Please provide supporting evidence for your specific claim in yellow above, or withdraw it.

No, I said nothing similar to that. But using the example of water, it is clear that water is essential to living things. Every abiogenetic hypothesis requires water!. So water by itself is in the non-living category (abiotic). It is not dead, because it has never been alive. But it is necessary and affects all life. I don't think that, nor do I imply that. I have provided an unequivocal definition of life. And recently, I have embraced the grey scale analogy to identify living, non-living, and dead. It works. All non-living things are in the grey area, living things are white, and dead things are black.The faithful evolutionary continuum from non-living to living through some form of chemical evolution is just speculative hypotheses at this moment. So I reject that there is a "pathway to life'. Water is abiotic, and of course necessary for life. Yes, really. That's exactly what we observe! All life comes from pre-existing life. This concept is perfectly consistent with cell theory and the law of biogenesis. We have a perfectly normal cell, and we have a viral infected cell. The virus is only alive in the sense that it is part of the original cell, and that now that it is within the cell it is disturbing and disorganizing the cell usually until it explodes the cell and releases the virions. Then those non-living virions hang around until they find another host.I think you would agree that poisons are abiotic and non-living. Yet they affect cells by disturbing their organization to such and extent that they destroy the cell. I think many doctors would agree that a virus can be interpreted as a very specific type of organic poison. In fact, they use the term "viral food poisoning" all the time. That list is miniscule, but their definition is clear...

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In biology and ecology, abiotic components or abiotic factors are non-living chemical and physical parts of the environment that affect living organisms and the functioning of ecosystems. Abiotic factors and phenomena associated with them underpin all biology. Abiotic component - Wikipedia

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I think a virus is a perfect example by observational evidence that it is a "non-living chemical and physical part of the environment that affects living organisms and the functioning of ecosystems."And at the same time there is no evidence that a virus is "on the pathway to life".

He He! That's OK, I about spit out my coffee when I read this!Because that's exactly what abiogenesis is all about!

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Abiogenesis (Brit.: /ˌeɪbaɪ.ɵˈdʒɛnɨsɪs/ AY-by-oh-JEN-ə-siss[1] U.S. English pronunciation: /ˌeɪˌbaɪoʊˈdʒɛnᵻsɪs/),[2] or biopoiesis,[3] is the natural process of life arising from non-living matter, such as simple organic compounds.[4][5][6][7] It is thought to have occurred on Earth between 3.8 and 4.1[8] billion years ago, and is studied through a combination of laboratory experiments and extrapolation from the genetic information of modern organisms in order to make reasonable conjectures about what pre-life chemical reactions may have given rise to a living system.[9]
Abiogenesis - Wikipedia

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Ok let's examine your "strange" ideas.White=Living=meets all seven (7) criteria of life. OK, I will accept that. Now lets look at grey. Grey=some of the 7 criteria..anywhere from 1-6. Ok, so by those two definitions Grey is not alive which unfortunately makes it non-living. Now you and others have semantically called it "pre-life", "proto cells", "self-replicatiing molecules", and probably a whole lot of other things. But They are not alive by your own criteria. So for your model to be consistent and not self refuting, both the grey and the black are non-living. So by your criteria and model, anything less than living is non-living. Sorry to disappoint you but I had a good laugh.

Percy, you need to think this through logically. You just refuted yourself in two sentences. You just said that we cannot specifically define "living" and "non-living". Then you said specifically that a dog is "alive" and Lead is "non-living".That's why there at least equivocating characteristics of life that allow you to somewhat discern that a dog is "alive' and a block of lead is not. But that leaves us in just as bad a position scientifically, because we have sacrificed biological science to equivocating terms. Which logically is not good either.

Ok, let's assume for a moment it is in the grey area, and the grey area is not a self refuted concept as already identified by the kid.(you are arguing like all the others.)In the abiogenesis history from non-life towards life, just how did virions evolve? Evidence please? Or hypotheses please? Before any cellular life existed, what chemical mechanism causes a virion to evolve?Or, are you saying that virions evolved after living cells evolved?Also, you just said you believe viruses are alive which contradicts your classification of "(1) White = Living, cellular organisms". Do you want to be contradictory, or do you want to correct this?Edited by AlphaOmegakid, : Added stuff