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Author Topic:   Life - an Unequivicol Definition
herebedragons
Member (Idle past 92 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(4)
Message 132 of 374 (773275)
11-27-2015 4:16 PM
Reply to: Message 115 by RAZD
11-25-2015 12:44 PM


Re: try again
A couple comments on this whole line of discussion... (not just directed at you, but regarding this whole issue)

Yet it doesn't explain the existence or evolution of viruses, nor does it allow for RNA life forms, and this is a failure.

1. This whole "definition of life" discussion is much like discussions about what species are; we intuitively know what constitutes a species, but to create a standard definition that applies in every single case proves to be elusive - biology is just messy. In the end, just as with species distinctions, scientists duke it out arguing in the literature as to whether a particular organism is "alive" or not until eventually there is a consensus reached. Ten to twenty years ago, it was pretty much the consensus that viruses were not alive. Now, it depends on who you ask. I heard a virologist on NPR this morning who referred to viruses as "organisms" that are alive. So the thinking about whether viruses are alive or not is shifting towards the "yes" side; not because definitions are changing or because scientists are being equivocal, but because we are changing how we view these grey areas.

Your definition is like saying only right hands are hands, and left hands don't qualify as hands because they aren't right hands.

2. AOkid's attempt to nail down a definition of "life" strikes me as an attempt to erase the blurry boundary between living things and non-living things in order to claim there is no transitional steps between living and non-living. Just as creationists define Archeopteryx as a bird and then claim it is not a transitional fossil between non-avian, feathered theropods and modern birds. In the same way, by his definition, viruses are not in this blurry area between living and non-living; they are simply defined as non-living.

Your definition shows A boundary event in the evolution of life, just as the evolution of eukaryotes shows a boundary event in the evolution of life, but we don't consider prokaryotes to be non-life because they don't fit the definition of eukaryotic life. This is an arbitrary choice, rather than one based on facts.

3. Right, life cannot be defined it is only described. That is why being overly specific and saying for example, "uses ATP" is inappropriate. Saying "All know life utilizes ATP as the main energy carrying molecule" would be appropriate, because it is descriptive not prescriptive.

4. I think your attempt to define life as "anything capable of evolution" is also problematic, IMO. I am not sure I can explain exactly why I don't like that definition, but it seems to require too many caveats and additional explanations, otherwise it simply means "anything that can change over time."

I think we should stick to the time-tested, simple description of life we all learn in school.

Life has (1) self-contained and organized structures (2) the ability to convert chemicals into metabolic and structural components (3) the ability to regulate it's metabolism (4) the ability to grow (5a) the ability to reproduce (5b) heritable traits (6) the ability to adapt to its environment (7) the ability to respond to stimuli

I would argue that viruses ARE capable of all the above within a suitable environment (regulate metabolism is questionable but all the rest seem solid).

I think the above "definition" is simple enough and is thoroughly descriptive of life as we know it. It is not too specific about any of the processes so some as of yet unknown life could still fit this definition.

But who knows, we may someday need to update the definition somewhat to accommodate new discoveries.

HBD


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 115 by RAZD, posted 11-25-2015 12:44 PM RAZD has replied

Replies to this message:
 Message 138 by RAZD, posted 11-30-2015 11:58 AM herebedragons has taken no action

  
herebedragons
Member (Idle past 92 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(3)
Message 164 of 374 (773460)
12-02-2015 12:57 PM
Reply to: Message 157 by AlphaOmegakid
12-02-2015 7:59 AM


Re: Black White or Grey?
So 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= Dead

Your position just keeps getting stranger. Why would you put abiotic materials (which means "not biotic" or "not derived from living organisms") as the "grey" area between living and dead? That make NO sense at all.

I'm pretty sure Tanypteryx will spit out his coffee when he sees that you think he was agreeing with you.

The grey scale should be interpreted as:

White = living - meets ALL the criteria for living creatures. I listed my version of this list in Message 132

quote:
(1) self-contained and organized structures (2) the ability to convert chemicals into metabolic and structural components (3) the ability to regulate it's metabolism (4) the ability to grow (5a) the ability to reproduce (5b) heritable traits (6) the ability to adapt to its environment (7) the ability to respond to stimuli

Black = Non-living - meets NONE of the criteria listed above

Grey = Meets SOME of the criteria listed above, but not all of them.

Viruses exhibit at least 5 of the above criteria and arguably all of them when it is within a suitable host cell. So then viruses are in this grey area between living organisms and non-living, abiotic materials - NOT between living and dead. Abiotic materials are not dead, they never were alive in the first place. If viruses are not alive, then they cannot be killed.

ABE: Crystals may have only 1 (or maybe 2) of these characteristics. Self-replicating RNA may have 3 of these characteristics, etc.

Dead organisms become organic matter, which when broken down may become part of abiotic substrates, such as soil, but they are still considered different from actual abiotic materials. We can recognize matter that originated in living organisms because of the way they can use carbon atoms. I know of no abiotic processes that can use carbon like living organisms do. Which makes me wonder why did you not include "carbon-based" in your definition of "living"?

I think this model works very well within Biology and especially well with my definition of life.

I wasn't aware there was really a problem in Biology regarding this issue. Sure some things are hard to classify, even when it comes to a seemingly simple question as to whether the subject is a living organism or not. But such is Biology. As much as we would like everything to fit in nice neat categories, things just are reluctant to allow us such amenities.

So this all makes me wonder what your motive is for wanting such a cut and dried definition of "life." What would such a definition accomplish that cannot be accomplished using the standard criteria?

HBD

Edited by herebedragons, : added ABE portion


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 157 by AlphaOmegakid, posted 12-02-2015 7:59 AM AlphaOmegakid has replied

Replies to this message:
 Message 167 by AlphaOmegakid, posted 12-02-2015 2:39 PM herebedragons has replied

  
herebedragons
Member (Idle past 92 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(2)
Message 180 of 374 (773506)
12-02-2015 11:08 PM
Reply to: Message 167 by AlphaOmegakid
12-02-2015 2:39 PM


Re: Black White or Grey?
Because that's exactly what abiogenesis is all about!

That's funny, I thought we were discussing how we define life, not abiogenesis. I suspected this was a bait-n-switch.

And besides, abiogenesis doesn't state that rocks are somewhere on a spectrum between dead and alive.

Now you and others have semantically called it "pre-life", "proto cells", "self-replicatiing molecules", and probably a whole lot of other things.

That's weird, I don't remember saying that. Maybe someone hacked my account and posted those words in my name. Maybe I better change my password!

I wouldn't have said "pre-life," "proto-cells," or a "whole lot of other things" since we aren't talking about abiogenesis, but just how to define and identify life.

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.

Except that non-living, "black" was defined as having NONE of the characteristics so the "grey" doesn't meet that definition either... so it is neither living nor non-living, but somewhere in between.

So by your criteria and model, anything less than living is non-living.

Or is it "anything more than non-living is living"??

SO if you don't accept that viruses are alive, that's fine. But it doesn't change the situation with abiogenesis. What you are doing is trying to alter the definition of life so you can use that definition to show that abiogenesis is wrong. Not a very effective move.

By the way, I am not an advocate of abiogenesis (at least not the naturalistic version). All I know is that at one time in the history of the earth there was no life and then at some point later, there was life.

HBD

Edited by Admin, : except => accept


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 167 by AlphaOmegakid, posted 12-02-2015 2:39 PM AlphaOmegakid has taken no action

  
herebedragons
Member (Idle past 92 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(4)
Message 208 of 374 (773558)
12-03-2015 7:51 PM
Reply to: Message 186 by AlphaOmegakid
12-03-2015 10:46 AM


Re: Black White or Grey?
Yours, and others claims of my definition as being arbitrary are false. Please Identify how my definition meets any part of the definition of being arbitrary.

I will give you an example to explain why we are saying your line is arbitrary. Let me propose a new, unequivocal definition for life:

Life; living = organisms that are made up of cells that are differentiated into tissues and that possess a digestive cavity that is lined with specialized cells (so only metazoans are alive)

Objections? You might say that the definition does not include all known life such as protozoans and bacteria.

But I would respond that protozoans and bacteria are not alive according to my definition and therefore are not part of all known life.

Why is this definition wrong?

Or how about a different definition...

Life; living = any assemblage of chemicals that can grow and multiply.

Objections? You might say that this definition includes things we know are not alive such as crystals.

But I could respond that according to the definition, they ARE alive and thus the unequivocal position is that crystals are alive.

Why is drawing the lines where I did any less arbitrary than drawing them any where else?

So... back to a more reasonable scale. Why do you not draw the line between life and non-life so that viruses are included in the life category? Is ATP really the true indicator that something is alive and how do you know? Because all known life uses ATP? Maybe, but before you can use the reasoning "all know life" you must first decide what is alive BEFORE you can formulate the definition, so the definition isn't what defines life but it is the criteria used before creating the definition. That is a tautology.

So Biologists will be sticking with the standard definition and they will continue to recognize that there are organism that do not fit neatly into the definition.

HBD


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 186 by AlphaOmegakid, posted 12-03-2015 10:46 AM AlphaOmegakid has taken no action

  
herebedragons
Member (Idle past 92 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(2)
Message 258 of 374 (773829)
12-09-2015 5:13 PM
Reply to: Message 255 by AlphaOmegakid
12-09-2015 1:05 PM


Re: the goldfish in the baggie problem.
Chloroplasts however only meet part of the definition. You excluded the part about the synthesis of the enzymes used in making the ATP. This does not happen within a chloroplast.

Yes it does. Chloroplasts DO have DNA and even have the gene for ATP synthase as well as some other energy related genes.

Chloroplast DNA

HBD


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 255 by AlphaOmegakid, posted 12-09-2015 1:05 PM AlphaOmegakid has taken no action

  
herebedragons
Member (Idle past 92 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(1)
Message 277 of 374 (773987)
12-11-2015 10:15 PM
Reply to: Message 274 by AlphaOmegakid
12-11-2015 5:23 PM


Re: The horse is just about dead!
But here's the rub! You can't have a continuum between harbor/non-harbor, ocean/non-ocean,

So which category does the open ocean fit into? "harbor" or "non-harbor"? Non-harbor. And you already agreed that there is a continuum between harbor and ocean, which in this case ocean is "non-harbor," so there is a continuum between harbor and "non-harbor."

What category does fresh water river fit into, "ocean" or "non-ocean"? "Non-ocean" and so we can have a continuum between ocean and non ocean

And so on...

You are simply engaging in some weird kind of word-play. Who uses terms like "non-harbor" and "non-ocean" anyway???

Here's the really funny thing, this line of reasoning does nothing to help your actual argument. What you are really arguing is that abiogenesis cannot of happened because life does not come from non-life. Now, let's consider your line of reasoning in that context.

Let's say we identify 7 characteristics that make something unambiguously alive. Then we identify various entities that have some, but not all of those characteristics. Then we line those entities up in order and hypothesize that this is the progression from non-life to life. So the progress looks like the list below where the numbers represent the number of characteristics that each entity has.

0 --> 1 --> 2 --> 3 --> 4 --> 5 --> 6 --> 7

Now your position, which you have painstakingly developed a "unambiguous definition" for, is that only if it has all 7 characteristics, is it alive; or in other words, the line between living and non-living is between the 6 and the 7.

However, maybe I draw the line between 5 and 6. And someone else draws the line between 3 and 4 and yet another person thinks the line is between 0 and 1 (so even 1 of the seven characteristics is enough to call it alive).

First of all, what makes any of the above positions better than the others?

And secondly, what difference does it make? You still have the progression. At some point in that line, where ever you draw the line, you have non-life going to life.

As entertaining as it may be, I don't think this line of argument can accomplish what you think it will.

Did that sink in? Or is it still blowing by?

Just because we don't agree with your premise doesn't mean we don't get it, it just means we think it is wrong. You are the one who doesn't seem to "get it" - even a simple concept like a continuum. Your "unambiguous definition" is just too simplistic and too stringent and doesn't address the complexities of life. And besides, it doesn't really make a difference to your central argument.

HBD


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 274 by AlphaOmegakid, posted 12-11-2015 5:23 PM AlphaOmegakid has taken no action

  
herebedragons
Member (Idle past 92 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(2)
Message 316 of 374 (774413)
12-17-2015 1:39 PM
Reply to: Message 315 by New Cat's Eye
12-17-2015 12:48 PM


Re: Let white = life and black = non-life
And you really got to stop contradicting yourself:

quote:
I am in no way creating any dichotomy.

quote:
It is absolutely impossible and logically inconsistent to have a continuum between non-life and life.

Cue a 300+ post discussion about what a dichotomy is...

HBD

Edited by herebedragons, : typo


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 315 by New Cat's Eye, posted 12-17-2015 12:48 PM New Cat's Eye has taken no action

Replies to this message:
 Message 322 by AlphaOmegakid, posted 12-18-2015 9:31 AM herebedragons has taken no action

  
herebedragons
Member (Idle past 92 days)
Posts: 1517
From: Michigan
Joined: 11-22-2009


(1)
Message 343 of 374 (774710)
12-21-2015 11:36 AM
Reply to: Message 341 by AlphaOmegakid
12-21-2015 10:58 AM


Re: End of discussion!
Stop it, you're not a martyr; neither are you restricted from pursuing your argument, you just need a different approach. If you accept a continuum between chemicals and life, then what's the problem? Demonstrate that there is a non-arbitrary point at which we can separate living beings from non-living beings. That is the point of your proposed definition of life. Why is the production of ATP not an arbitrary line? What is so special about ATP as opposed to say GTP or some of the other energy carrying molecules that others have mentioned? What would having such a hard distinction between life and non-life be helpful to our study of biology?

There are a lot of questions that have been raised that you have not addressed; and they don't require discussion of a continuum to answer. Address what your opponents have proposed as being flaws in your definition.

Yet not one poster other than me wants to use it as the model or analogy.

What are you talking about?? We have agreed with that. What you need to show is why your line between life and non-life is not an arbitrary distinction.

As far as my definition of life, I was looking forward to rebutting RAZD, but now I can't. Definitions of words and their application are the only way I can defend it. And that's been ruled out by fiat as well.

No it hasn't. Repetitive and meaningless arguments based on highly literal meanings of words is what has been ruled out. The arguments can be made based on common usage of words and logic and most of all, evidence that supports a position. However, I think the ruling goes both ways... some of the arguments from the other side were also using this type of tactic and Percy's ruling applies to them as well (see Message 338).

Definitions may indeed be important to an argument, but they can't be the whole of the argument...

HBD


Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca

"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.

Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.


This message is a reply to:
 Message 341 by AlphaOmegakid, posted 12-21-2015 10:58 AM AlphaOmegakid has replied

Replies to this message:
 Message 345 by AlphaOmegakid, posted 12-22-2015 12:50 PM herebedragons has taken no action

  
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