Calculating the Odds of life

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Re: Calculating the Odds of life

Postby old6598 » Wed Nov 17, 2010 8:24 am

Maybe the most that we can achieve is that we may know some general conditions where molecules polymerize, we can see some evolution or some portions, we can see some reactions and some primitive organisms evolve slightly, but past that we won't see: it is like history, we know groups of people conflict, change organization, change power structures and interactions constantly (as man is the infinitely programmable machine, people and groups of people can be programmed (and program themselves) to act and interact in any of an infinite number of different ways), but we can never predict the exact sequence of events, like WW1 in Europe and then hitler in 1939, and WWII, etc. That exact sequence is just pure chance, and so is the exact structure of the simplest cell, let alone the exact structure of an ape or human...

The most important results in Science deal with what we cannot know, what our limits are, in what box we live in, where the edges of the box are: so we can't travel faster than light, we can't measure position and velocity to infinite precision at the same time (Uncertainty principle) and probably we can't predict a precise given sequence of events exactly because there is no predetermined sequence, the sequence just happens, just occurs with no deeper reason or cause.

A bit like saying 4 guys playing 2 guitars, bass and drum will create music: but that those four guys will exactly create the 10 Beatles albums is totally unpredictable because things like that just happen with no deeper cause. Determinism is defeated.

But maybe I am wrong, and in virtual reality environment you can simulate the possibility to predict exact sequences no matter how far fetched...
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Re: Calculating the Odds of life

Postby Ganapati » Wed Nov 17, 2010 1:12 pm

old6598 wrote:Maybe the most that we can achieve is that we may know some general conditions where molecules polymerize, we can see some evolution or some portions, we can see some reactions and some primitive organisms evolve slightly, but past that we won't see

Nor do we need to. Evolutionary theory, for those who have taken the time to read and understand it, is quite compelling. It addresses the almost unimaginable diversity found starting from very simple life forms and a set of "laws" that can be said to operate whenever there are finite resources and entities capable of replicating indefinitely.

However, what is not so compelling is the evidence for abiogenesis. At the moment, it is a faith position.
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Re: Calculating the Odds of life

Postby Xunzian » Tue Nov 30, 2010 6:18 pm

Ganapati wrote:Would you be happy with 'highly probable'? Sounds technical enough for me. Of course, it is still a fading out definition. I suppose different people would be satisfied with different quantitative values. Has anybody quantified the probability so far?


What are the variables you would use to calculate such a probability? There are too many variables and we are (at present) too ignorant to begin a proper calculation of them.


Size matters in that the probability of one of a random combination is much higher if the size is small than if the size is large. Stability is certainly a function of the environment. I never talked about stability in the present environment. If we can guess intermediate molecules, guess and demonstrate the environment was stable in and if the progression of such enviroments is what we would expect from the laws of physics, we would have a credible case for abiogenesis. As for presence of molecular oxygen in today's environment, I am not aware of that being a constraint in our ability to simulate environments that were drastically different from what exists today. Can you direct me to information that presents this to be the limitation in our ability to simulate pe-life environments in the laboratory?


We can create anoxic environments in laboratories, it happens all the time. The Miller–Urey and Jose Oro experiments are pretty classic examples of trying to recreate the reducing environment of the early Earth atmosphere and plenty of compounds involved in present life are formed there. While there is some controversy surrounding the specifics of these experiments, other variations accounting for those controversies still produce materials that would be sufficient for early "life" in significant quantities.

I am not aware of any experiment where a self-replicating molecule was formed without deciding a-priori what its structure was going to be, something that is a must for abiogenesis. That anyone can arrange pebbles on a beach into a long sentence in English, does not prove that such a pattern could emerge by physical forces. I would be glad to know of any such successful experiment.


Actually, most of the self-replicating RNA demons were not designed a priori but rather through a selective process starting with Q beta. Randomly messing around with Q beta to see what happens is hardly an a priori approach, it is an experimental one where selection is at play.
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Re: Calculating the Odds of life

Postby rasava » Sun Dec 05, 2010 3:57 am

I basically echo one of Xunzian's points - It is difficult to determine the probability of life occurring in the universe without knowing for sure what really can be defined as life and what kinds of life are out there already in the universe. It's a pretty wild extrapolation from the perspective of the entire universe to say that our life is the only type there can be, given that we're currently locked on one planet out of quadrillions without any larger perspective on what the universe outside of us really contains.

Of course, when has that stopped philosophers from asking questions before? But let's define life first at least. Current thinking is that all life requires water, but in the end that too is limited to what we know on Earth. This then leads us to something akin to old-school metaphysics - a worthy exercise but it is nonetheless important to recognize it at the outset. Our body of Natural Science is far too limited to be of much use in narrowing this question down.
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Re: Calculating the Odds of life

Postby Humpty » Sun Dec 05, 2010 5:00 am

rasava wrote:It is difficult to determine the probability of life occurring in the universe without knowing for sure what really can be defined as life and what kinds of life are out there already in the universe.

This sentiment is completely correct. It was in the news recently: a kind of bacteria completely unlike any other lifeform previously discovered. Apparently, it uses different building blocks than every other known life form. It uses Arsenic.

http://www.thatsfamous.com/6832-nasa-sc ... alifornia/

Scientists in the United States have made a phenomenal breakthrough after they found a bacteria that thrives on Arsenic in Mono Lake, California. The most shocking discovery in this bacteria is that it is living with another element in its DNA and it is basically Arsenic. Every living organism on earth are built of six basic elements which constitute in the DNA they are – Carbon, Oxygen, Nitrogen, Hydrogen, Sulfur, and Phosphorus.

Now here is the twist, if such sort of bacteria is freely living on earth, in an unimaginable environment which lacks most of the building blocks or elements of a DNA, then there is also a huge possibility that there could be life outside planet earth.

The questions that have been pondering scientists for many years has been finally answered, and yes life can also exists without the basic elements that are found suitable on earth. This means that there can be a massive window of opportunity that life can exist in many parts of our universe, if the surrounding atmosphere and environment helps them to exist. Life can adapt to its environment around it, the environment does not adapt to life.
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Re: Calculating the Odds of life

Postby Ganapati » Tue Dec 07, 2010 7:33 am

Xunzian wrote:
Ganapati wrote:Would you be happy with 'highly probable'? Sounds technical enough for me. Of course, it is still a fading out definition. I suppose different people would be satisfied with different quantitative values. Has anybody quantified the probability so far?


What are the variables you would use to calculate such a probability? There are too many variables and we are (at present) too ignorant to begin a proper calculation of them.

Until we can demonstrate the path and quantify the probability, abiogenesis will remain a faith position.
We can create anoxic environments in laboratories, it happens all the time. The Miller–Urey and Jose Oro experiments are pretty classic examples of trying to recreate the reducing environment of the early Earth atmosphere and plenty of compounds involved in present life are formed there. While there is some controversy surrounding the specifics of these experiments, other variations accounting for those controversies still produce materials that would be sufficient for early "life" in significant quantities.

Well, having the components and demonstrating the path are entirely different things. Demonstrating that amino acids could form in an abiotic environment is a step closer to proving abiogenesis, but doesn't constitute proof by itself.
Ganapati wrote:I am not aware of any experiment where a self-replicating molecule was formed without deciding a-priori what its structure was going to be, something that is a must for abiogenesis. That anyone can arrange pebbles on a beach into a long sentence in English, does not prove that such a pattern could emerge by physical forces. I would be glad to know of any such successful experiment.

Actually, most of the self-replicating RNA demons were not designed a priori but rather through a selective process starting with Q beta. Randomly messing around with Q beta to see what happens is hardly an a priori approach, it is an experimental one where selection is at play.

If this is an experiment where self-replicating RNA molecules were formed starting from molecules that have been demonstrated to have been capable of forming in an abiotic environment, please link me to it. I am not aware of Q beta replicase being formed in abiotic environments.
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Re: Calculating the Odds of life

Postby Ganapati » Tue Dec 07, 2010 7:45 am

rasava wrote:I basically echo one of Xunzian's points - It is difficult to determine the probability of life occurring in the universe without knowing for sure what really can be defined as life and what kinds of life are out there already in the universe. It's a pretty wild extrapolation from the perspective of the entire universe to say that our life is the only type there can be, given that we're currently locked on one planet out of quadrillions without any larger perspective on what the universe outside of us really contains.

So it would be the probability of life as we know it, which is good enough for scientific research, if not for philosophical curiosity.
But let's define life first at least.

The broadest definition would be: self-replicating pieces of information that are capable of organising the matter around to sustain the information and self-replication process.
Current thinking is that all life requires water, but in the end that too is limited to what we know on Earth. This then leads us to something akin to old-school metaphysics - a worthy exercise but it is nonetheless important to recognize it at the outset. Our body of Natural Science is far too limited to be of much use in narrowing this question down.

That is only one we know. Until we find other forms of life that fit the definition, it will have to do.
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Re: Calculating the Odds of life

Postby Ganapati » Tue Dec 07, 2010 7:59 am

Humpty wrote:
rasava wrote:It is difficult to determine the probability of life occurring in the universe without knowing for sure what really can be defined as life and what kinds of life are out there already in the universe.

This sentiment is completely correct. It was in the news recently: a kind of bacteria completely unlike any other lifeform previously discovered. Apparently, it uses different building blocks than every other known life form. It uses Arsenic.

http://www.thatsfamous.com/6832-nasa-sc ... alifornia/

Scientists in the United States have made a phenomenal breakthrough after they found a bacteria that thrives on Arsenic in Mono Lake, California. The most shocking discovery in this bacteria is that it is living with another element in its DNA and it is basically Arsenic. Every living organism on earth are built of six basic elements which constitute in the DNA they are – Carbon, Oxygen, Nitrogen, Hydrogen, Sulfur, and Phosphorus.

Now here is the twist, if such sort of bacteria is freely living on earth, in an unimaginable environment which lacks most of the building blocks or elements of a DNA, then there is also a huge possibility that there could be life outside planet earth.

The questions that have been pondering scientists for many years has been finally answered, and yes life can also exists without the basic elements that are found suitable on earth. This means that there can be a massive window of opportunity that life can exist in many parts of our universe, if the surrounding atmosphere and environment helps them to exist. Life can adapt to its environment around it, the environment does not adapt to life.

Well, not everyone seems to think the study's conclusions are reliable. NASA's arsenic microbe science slammed
But Redfield disagreed, writing that the paper "doesn't present ANY convincing evidence that arsenic has been incorporated into DNA (or any other biological molecule).

In an interview Monday, Redfield said the methods used by the researchers were so crude that any arsenic they detected was likely from contamination. There is no indication that the researchers purified the DNA to remove arsenic that might have been sticking to the outside of the DNA or the gel the DNA was embedded in, she added. Normally, purifying the DNA is a standard step, Redfield said: "It's a kit, it costs $2, it takes 10 minutes."

She also questioned why the researchers analyzed the DNA while it was still in the gel, making the results more difficult to interpret: "No molecular biologist would ever do that."

Redfield also disagreed with the paper's conclusion that the bacteria had to rely on arsenic to build molecules such as DNA because there wasn't enough phosphate (a form of phosphorus) available in the samples with the lowest levels. Her arithmetic showed that in fact, there was enough phosphate to account for the amount of bacteria that grew.

"That shocked me," she said.

Redfield added that there was actually very little arsenic in the DNA of bacteria grown in an environment high in arsenic and low in phosphorus. In fact, the amount was only twice that of the cells grown without arsenic: "That's a level of difference that could be easily explained by very minor contamination."
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Re: Calculating the Odds of life

Postby Humpty » Tue Dec 07, 2010 8:07 am

even if the results of the study i linked are incorrect, that doesn't preclude the possibility that life can arise under drastically different conditions than Earth's.
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Re: Calculating the Odds of life

Postby Ganapati » Wed Dec 08, 2010 4:04 pm

Humpty wrote:even if the results of the study i linked are incorrect, that doesn't preclude the possibility that life can arise under drastically different conditions than Earth's.

Of course, not!

Nothing is precluded as a possibility. Green-headed beings with antenna are certainly a possibility that cannot ever be precluded, just as the presence of an omnipotent, omniscient creator can never be. But I doubt they should ever enter a serious discussion on that count alone.
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Re: Calculating the Odds of life

Postby rasava » Thu Dec 09, 2010 3:08 am

Hello Ganapati:

The point is that we don't have a sufficient domain of knowledge on life to even know if our probability estimates of life, whether as we know it or as we don't know it. Calculating the probability of whether a quarter will land heads or tails starts with the knowledge of the set of alternatives for the facing of the coin, the domain of possibilities. Life as we know it on Earth may be not exist anywhere else, but any planet that sustains life has a different form. The principle of life may be a generation of self-motive bodies using the chemicals available on the planet provided certain solar characteristics exist. In such a definition, life made of silicon that floats through a gas giant and which drinks liquid methane instead of water would not be life as we know it, and the standard or definition of life would be so out of touch with our probability characterizations that they would be useless. Heck, life may originate from persistent sound waves on a planet - how would our probability calculations or your definition account for that? These are speculations on other types of life to be sure, but our very narrow frame of reference in a universe with quadrillions of planets makes any calcuations on our part equally speculative or purely in the realm of metaphysics, not natural science.

As to your argument that our knowledge of life's current forms will "have to do", I would ask "have to do for what?" What good will they serve as a scientific foundation when we do not have sufficient observations and data to draw a conclusion under the Scientific Method?

The answer is to forget grounding such discussions in science and instead put it where it belongs - as a metaphysical inquiry. That's not such a bad thing.
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Re: Calculating the Odds of life

Postby Ganapati » Thu Dec 09, 2010 5:17 am

rasava wrote:Hello Ganapati:

The point is that we don't have a sufficient domain of knowledge on life to even know if our probability estimates of life, whether as we know it or as we don't know it. Calculating the probability of whether a quarter will land heads or tails starts with the knowledge of the set of alternatives for the facing of the coin, the domain of possibilities. Life as we know it on Earth may be not exist anywhere else, but any planet that sustains life has a different form. The principle of life may be a generation of self-motive bodies using the chemicals available on the planet provided certain solar characteristics exist. In such a definition, life made of silicon that floats through a gas giant and which drinks liquid methane instead of water would not be life as we know it, and the standard or definition of life would be so out of touch with our probability characterizations that they would be useless. Heck, life may originate from persistent sound waves on a planet - how would our probability calculations or your definition account for that? These are speculations on other types of life to be sure, but our very narrow frame of reference in a universe with quadrillions of planets makes any calcuations on our part equally speculative or purely in the realm of metaphysics, not natural science.

There is one form of life we know exists and infinite forms that we don't know if they exist. We can define life as we know it to be the only possibility in the domain of possibilities and then proceed to calculate the probability of it. It may still be very difficult to compute it, but it will not be meaningless. If we have evidence about other forms that we are forced to concede are life, we will have to recalculate our probabilities, the domain of possibilities having changed.
As to your argument that our knowledge of life's current forms will "have to do", I would ask "have to do for what?" What good will they serve as a scientific foundation when we do not have sufficient observations and data to draw a conclusion under the Scientific Method?

When I said "it will have to do", I meant for a scientific enquiry. Science proceeds precisely based on available evidence that can be extrapolated. If we do not find a phenomena in our observations and by inference on earth or anywhere else, we don't go under the assumption it exists i.e, we proceed as if it did not exist.

Nothing is barred from speculation, but in order to make scientific sense, it needs to be more than speculation, it needs some supporting evidence. That is why if there exists evidence for life distinct from what we know it to be, it has to be considered. If not, it is pure speculation.
The answer is to forget grounding such discussions in science and instead put it where it belongs - as a metaphysical inquiry. That's not such a bad thing.

By that token anything can be taken out of the discipline of science, not just life. How do we know the laws of physics were the same before we discovered them? Perhaps they were all different with the consequences being exactly the same as we observed?

This can be discussed at a scientific level as well as a metaphysical level. Since the thread is in the natural sciences forum and used scientific terms, I chose a scientific approach to my responses rather than a metaphysical one.
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Re: Calculating the Odds of life

Postby rasava » Fri Dec 10, 2010 2:53 am

Ganapati:

I admit I don't see the complete uselessness of approaching it scientifically, and your arguments for doing so are sound enough. We're looking at it just from two different angles in the end. The key is to recognize the limts of scientific understanding in this area, and from reading your post I think we are aligned on that premise.
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Re: Calculating the Odds of life

Postby Xunzian » Wed Dec 15, 2010 8:55 pm

Ganapati wrote:Until we can demonstrate the path and quantify the probability, abiogenesis will remain a faith position.


What I think you mean to say here is that until that time abiogenesis will remain hypothetical. I don't think anyone (and certainly not myself) is claiming that abiogenesis is more than a hypothesis, though as a hypothesis it does have a fair deal of evidence supporting it as well as a great degree of explanatory power.

I'm not sure what you are trying to establish with this point, though.

Well, having the components and demonstrating the path are entirely different things. Demonstrating that amino acids could form in an abiotic environment is a step closer to proving abiogenesis, but doesn't constitute proof by itself.


Sure, I never claimed that. However, when we look at the evidence supporting abiogenesis I will say that the support in favor of abiogenesis is greater than the support in favor of any of the other hypotheses being thrown around at present (at least insofar as I'm aware). However, there still does remain a great deal of mystery left to be solved.

If this is an experiment where self-replicating RNA molecules were formed starting from molecules that have been demonstrated to have been capable of forming in an abiotic environment, please link me to it. I am not aware of Q beta replicase being formed in abiotic environments.


I've noticed a series of moving goalposts within this discussion, this being the latest of them. It went from, "We have nothing" to, "Well, show me this very specific experiment". This lends your entire argument a "god-of-the-gaps" feel to it, which is very weak ground to stand on both rhetorically and philosophically. Simply because unknowns do exist does not mean that the entire structure is unknown, unknowable, or that we are unable to understand it. But if you want a demonstration of possibility, these self-replicating RNA contains nucleotides that could be created under the abiotic conditions described and the shortest of them, 165 nucleotides, is significantly shorter than other nucleotides which have been created under simulated pre-biotic environments (some of which have reached around 400 nucleotides in length). While not a rigorous proof by any means, that does serve as a proof of concept.
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Re: Calculating the Odds of life

Postby Ganapati » Thu Dec 16, 2010 2:01 pm

Xunzian wrote:
Ganapati wrote:Until we can demonstrate the path and quantify the probability, abiogenesis will remain a faith position.


What I think you mean to say here is that until that time abiogenesis will remain hypothetical.

Yes.
I don't think anyone (and certainly not myself) is claiming that abiogenesis is more than a hypothesis, though as a hypothesis it does have a fair deal of evidence supporting it as well as a great degree of explanatory power.

Beg to differ. I find the evidence supporting it to be quite slim and its explanatory power being extremely limited.
I'm not sure what you are trying to establish with this point, though.

I was trying to establish the point, not something else with it. Frankly I find it very uncomfortable when an unproven scientific hypothesis, like abiogenesis, and a valid scientific theory, like evolution, are mentioned in the same context with the same degree of conviction. When discussing abiogenesis, we can leave evolution completely out, since evolution comes into play only after the first self-replicating forms appear.
If this is an experiment where self-replicating RNA molecules were formed starting from molecules that have been demonstrated to have been capable of forming in an abiotic environment, please link me to it. I am not aware of Q beta replicase being formed in abiotic environments.


I've noticed a series of moving goalposts within this discussion, this being the latest of them. It went from, "We have nothing" to, "Well, show me this very specific experiment". This lends your entire argument a "god-of-the-gaps" feel to it, which is very weak ground to stand on both rhetorically and philosophically. Simply because unknowns do exist does not mean that the entire structure is unknown, unknowable, or that we are unable to understand it. But if you want a demonstration of possibility, these self-replicating RNA contains nucleotides that could be created under the abiotic conditions described and the shortest of them, 165 nucleotides, is significantly shorter than other nucleotides which have been created under simulated pre-biotic environments (some of which have reached around 400 nucleotides in length). While not a rigorous proof by any means, that does serve as a proof of concept.

I am sorry you find that goalposts are being moved. When you mention something specific in response to a claim of nothing exists, why would you find it uncomfortable to show that the specific you mentioned meets the criteria?

I haven't read the artcile in the link, since the site requires registration. I will do so later.

But if all the components, nucleotides and the enzymes piecing them together to form the self-replicating RNA molecule are themselves known to be formed in pre-biotic environment and the only things controlled in the experiment were abiotic parameters, it would have demonstrated abiogenesis of some kind of life if not the one as we know it. If any of them is not known to have formed in a pre-biotic environment, it would have demonstrated little to someone who is not already assuming the validity of abiogenesis.
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Re: Calculating the Odds of life

Postby Xunzian » Thu Dec 16, 2010 6:33 pm

Ganapati wrote:Beg to differ. I find the evidence supporting it to be quite slim and its explanatory power being extremely limited.


May I ask on what grounds you base that conclusion off of?

I was trying to establish the point, not something else with it. Frankly I find it very uncomfortable when an unproven scientific hypothesis, like abiogenesis, and a valid scientific theory, like evolution, are mentioned in the same context with the same degree of conviction. When discussing abiogenesis, we can leave evolution completely out, since evolution comes into play only after the first self-replicating forms appear.


While they are occasionally mentioned together, I usually only see that occurring when the origin of life is mentioned as a critique of evolution. Within the confines of this thread, it was brought up because we need to first define what we mean by "life" before we can properly begin considering what conditions are necessary for it to arise and what their probabilities are.

I am sorry you find that goalposts are being moved. When you mention something specific in response to a claim of nothing exists, why would you find it uncomfortable to show that the specific you mentioned meets the criteria?


I don't have a problem providing the information -- clearly, as I did provide the information. I merely wanted to point out the regression being employed in your argument before it gets out of hand.

But if all the components, nucleotides and the enzymes piecing them together to form the self-replicating RNA molecule are themselves known to be formed in pre-biotic environment and the only things controlled in the experiment were abiotic parameters, it would have demonstrated abiogenesis of some kind of life if not the one as we know it. If any of them is not known to have formed in a pre-biotic environment, it would have demonstrated little to someone who is not already assuming the validity of abiogenesis.


You are displaying an ignorance of biochemistry here. Enzymes are protein catalysts. The RNA world hypothesis doesn't involve enzymes, it involves ribozymes, which are nucleotide catalysts. In this case, the ribozyme in question is an RNA polymerase which can replicate itself. What the paper describes is a self-replicating RNA molecule that is built from nucleotides which could have been present in the pre-biotic world and is short enough that it could have been generated in the pre-biotic world. As I said before, that seems a rather strong proof of concept in terms of the RNA world hypothesis within abiogenesis.
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Re: Calculating the Odds of life

Postby Ganapati » Fri Dec 17, 2010 8:49 am

Xunzian wrote:
Ganapati wrote:Beg to differ. I find the evidence supporting it to be quite slim and its explanatory power being extremely limited.


May I ask on what grounds you base that conclusion off of?

May I ask on what grounds you believe abiogenesis has "a fair deal of evidence supporting it as well as a great degree of explanatory power"? In the end, until something is proven (and I don't think you are claiming abiogenesis to have been proven), whether the evidence supporting it is "fair deal" or "slim" and the explanatory power "great" or "limited" is a judgment call. If I wanted to convert you to my judgment, I may make such an attempt. Since I am not interested in whether you, or anyone else, believe(s) abiogensis is true or not, I don't see much point in discussing what are clearly subjective judgments on the same objective basis.
I am sorry you find that goalposts are being moved. When you mention something specific in response to a claim of nothing exists, why would you find it uncomfortable to show that the specific you mentioned meets the criteria?


I don't have a problem providing the information -- clearly, as I did provide the information. I merely wanted to point out the regression being employed in your argument before it gets out of hand.

There isn't any regression being employed. Abiogenesis will remain hypothetical until either a living cell is created in a simulated but exclusively pre-biotic environment or its probability of happening computed rigorously and shown to be close to 1 over geological time.
But if all the components, nucleotides and the enzymes piecing them together to form the self-replicating RNA molecule are themselves known to be formed in pre-biotic environment and the only things controlled in the experiment were abiotic parameters, it would have demonstrated abiogenesis of some kind of life if not the one as we know it. If any of them is not known to have formed in a pre-biotic environment, it would have demonstrated little to someone who is not already assuming the validity of abiogenesis.


You are displaying an ignorance of biochemistry here. Enzymes are protein catalysts. The RNA world hypothesis doesn't involve enzymes, it involves ribozymes, which are nucleotide catalysts.

OK. So replace enzymes in what I said above with catalysts.
In this case, the ribozyme in question is an RNA polymerase which can replicate itself. What the paper describes is a self-replicating RNA molecule that is built from nucleotides which could have been present in the pre-biotic world and is short enough that it could have been generated in the pre-biotic world. As I said before, that seems a rather strong proof of concept in terms of the RNA world hypothesis within abiogenesis.

Are you referring to the higher probability of this self-replicating molecule being formed as one of the many possible random combinations of the nucleotides which were themselves capable of forming in a pre-biotic environment as opposed to a longer chain as "strong proof"?
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Re: Calculating the Odds of life

Postby kk23wong » Sun Dec 19, 2010 11:25 am

The struggles between determinism and randomness always come to the same conclusion.
Determinism trend to have subjective selection of information received (Psychology).
Randomness favors the scientific minds (e.g. Darwinism – everyone was born to be).
Randomness prevails.

The manipulation of the God, which I strongly believed in and repeated endlessly, comes from the natural role. The interconnection between the God (the cell nucleus and the mother cell) and the humankind (a part of the biosphere – Life Cycles of this planet) must be solid. The physical connections allow us to have communications. The gifted power of the God comes from birth. Free Will (our minds generated by the thinking regions / central nerve systems) allows us to have random despite of the God’s will.

Discovery is a rebellion to the rests. I guess many people were making jokes on Galileo when he was still a little nobody confronting the authorities (the teachings of the churches). “All truths are easy to understand once they are discovered; the point is to discover them.” My scientific hypothesis “Lives in Different Levels” reveals the true nature of lives. The hierarchy of lives has given us the concrete idea on how the universe works (the natural rules). This discovery is a natural course in human history because of the bloom of knowledge and the technological breakthroughs. Religions are too weak to convince our new generations in the scientific era. The existence of the God is correspondent to the cell nucleus. There must be oppositions when someone comes up with a new cosmology (or I have to say, it is more likely to be a discovery). The relationship between the God (Conscious Earth) and the humankind become much clearer. Human is undoubtedly a part of the biosphere and we are the “LIFE CYCLES (including reproduction with regards to its biological meanings)” of this planet.

Teru Wong
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Re: Calculating the Odds of life

Postby Xunzian » Tue Dec 21, 2010 6:25 am

Ganapati wrote:May I ask on what grounds you believe abiogenesis has "a fair deal of evidence supporting it as well as a great degree of explanatory power"? In the end, until something is proven (and I don't think you are claiming abiogenesis to have been proven), whether the evidence supporting it is "fair deal" or "slim" and the explanatory power "great" or "limited" is a judgment call. If I wanted to convert you to my judgment, I may make such an attempt. Since I am not interested in whether you, or anyone else, believe(s) abiogensis is true or not, I don't see much point in discussing what are clearly subjective judgments on the same objective basis.


I mentioned this earlier and you've been avoiding it ever since. Your rhetoric is really, really shoddy. Bringing up spurious points which have already been addressed isn't just poor philosophy, it is weak rhetoric. Not hacking it philosophically and rhetorically is a sad thing indeed.

But since you've asked, I've provided some of the evidence supporting abiogenesis in this thread. This is in contrast to other hypotheses regarding the origin of life where the evidence is scant if existent at all. As for the explanatory power, the origin of life remains a mystery. However, abiogenesis takes what we do know about pre-biotic conditions on Earth, what we know about life as it presently exists on Earth, and basic chemistry and manages to synthesize those elements into a coherent narrative.

If that doesn't convince you, I'd be curious to know why.

I am sorry you find that goalposts are being moved. When you mention something specific in response to a claim of nothing exists, why would you find it uncomfortable to show that the specific you mentioned meets the criteria?


I don't have a problem providing the information -- clearly, as I did provide the information. I merely wanted to point out the regression being employed in your argument before it gets out of hand.


There isn't any regression being employed. Abiogenesis will remain hypothetical until either a living cell is created in a simulated but exclusively pre-biotic environment or its probability of happening computed rigorously and shown to be close to 1 over geological time.


Kicking the goal-post once again, with the addition of a strawman! Really?

OK. So replace enzymes in what I said above with catalysts.


See the information I've provided previously.

Are you referring to the higher probability of this self-replicating molecule being formed as one of the many possible random combinations of the nucleotides which were themselves capable of forming in a pre-biotic environment as opposed to a longer chain as "strong proof"?


Since you seem unable to synthesize the evidence on your own:

Under pre-biotic conditions:
1) RNA components are formed.
2) Reducing conditions result in polymerization
3) RNA molecules can reach a size of around 400nt.

Couple those with:

4) Self-replicating ribozymes as short as 140nt have been observed.

Now, all I've claimed is a proof-of-concept. I'd say that those elements do represent a rather solid proof-of-concept.

Which is substantially more than other hypotheses going for them . . .
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Re: Calculating the Odds of life

Postby tentative » Tue Dec 21, 2010 11:32 pm

Coming in late on this, but... The ID game of numbers assumes one single instance of the right combination of molecules necessary to form self-replicating life. The numbers look overwhelmingly in favor of ID. But if you introduce just a tiny bit of reason, the pre-biotic "primordial soup" wouldn't have just one each of the necessary molecules to begin life. The soup would have literally trillions of possible combinations when the correct conditions for life "arrived". The only miracle of life is if it HADN'T happened.
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Re: Calculating the Odds of life

Postby Ganapati » Wed Dec 22, 2010 5:16 am

Xunzian wrote:
Ganapati wrote:May I ask on what grounds you believe abiogenesis has "a fair deal of evidence supporting it as well as a great degree of explanatory power"? In the end, until something is proven (and I don't think you are claiming abiogenesis to have been proven), whether the evidence supporting it is "fair deal" or "slim" and the explanatory power "great" or "limited" is a judgment call. If I wanted to convert you to my judgment, I may make such an attempt. Since I am not interested in whether you, or anyone else, believe(s) abiogensis is true or not, I don't see much point in discussing what are clearly subjective judgments on the same objective basis.


I mentioned this earlier and you've been avoiding it ever since. Your rhetoric is really, really shoddy. Bringing up spurious points which have already been addressed isn't just poor philosophy, it is weak rhetoric. Not hacking it philosophically and rhetorically is a sad thing indeed.

But since you've asked, I've provided some of the evidence supporting abiogenesis in this thread. This is in contrast to other hypotheses regarding the origin of life where the evidence is scant if existent at all. As for the explanatory power, the origin of life remains a mystery. However, abiogenesis takes what we do know about pre-biotic conditions on Earth, what we know about life as it presently exists on Earth, and basic chemistry and manages to synthesize those elements into a coherent narrative.

If that doesn't convince you, I'd be curious to know why.

The funny thing about science is no one need be convinced by a mere hypothesis nor explain why he remains unconvinced. However I will indulge you. For me, abiogenesis as a hypothesis for the currently known life is convincing only when life in some form is demonstrated to be capable of forming in an abiotic environment. Until then I will consider all the "evidence" offered to be slim.

The only thing that "coherent narrative" achieves is the absence of need for anything that is as yet unknown to science. None too convincing for me. If that is proven to be the case, so be it. If not, that in itself isn't anything impressive for me. That we have discovered and understood all possible phenomena is a position that reminds me of Max Planck who discouraged students from going into research in physics because there was nothing left in physics to discover, only to account for the mass of the nucleus (neutron was discovered much later). But to his credit, he at least correctly identified those that defied any valid explanation in his day, failure of the Michaelson-Morley experiment (leading to Relativity) and problems in black-body radiation (leading to Quantum Mechanics).

Pretending omniscience is not science and offering a narrative that validates such pretentions isn't a merit in itself.
I am sorry you find that goalposts are being moved. When you mention something specific in response to a claim of nothing exists, why would you find it uncomfortable to show that the specific you mentioned meets the criteria?


I don't have a problem providing the information -- clearly, as I did provide the information. I merely wanted to point out the regression being employed in your argument before it gets out of hand.


There isn't any regression being employed. Abiogenesis will remain hypothetical until either a living cell is created in a simulated but exclusively pre-biotic environment or its probability of happening computed rigorously and shown to be close to 1 over geological time.


Kicking the goal-post once again, with the addition of a strawman! Really?

You perhaps never saw the goal post. Where did you assume it was?
Are you referring to the higher probability of this self-replicating molecule being formed as one of the many possible random combinations of the nucleotides which were themselves capable of forming in a pre-biotic environment as opposed to a longer chain as "strong proof"?


Since you seem unable to synthesize the evidence on your own:

Under pre-biotic conditions:
1) RNA components are formed.
2) Reducing conditions result in polymerization
3) RNA molecules can reach a size of around 400nt.

Couple those with:

4) Self-replicating ribozymes as short as 140nt have been observed.

Now, all I've claimed is a proof-of-concept. I'd say that those elements do represent a rather solid proof-of-concept.

Which is substantially more than other hypotheses going for them . . .

I am not concerned with what different hypotheses have to offer, I am not attempting to convince you with a hypothesis different from yours. Your hypothesis doesn't meet the minimum conditions needed for me to consider it. If you are arguing the case for why your pet hypothesis needs more funding than another, go right ahead and argue with those funding such initiatives. I am not one.

I am concerned with whether something can considered a valid scientific theory or not.

Can you let me know how abiogenesis is falsifiable?
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Re: Calculating the Odds of life

Postby Ganapati » Wed Dec 22, 2010 5:42 am

tentative wrote:Coming in late on this, but... The ID game of numbers assumes one single instance of the right combination of molecules necessary to form self-replicating life. The numbers look overwhelmingly in favor of ID.

It is funny that those who believe in abiogenesis think the only reason it can be rejected is because someone is proposing an alternate hypothesis based on Intelligent Design. Any hypothesis can be rejected without proposing an alternate hypothesis either because the proposed hypothesis is not falsifiable and hence not scientific or because there isn't enough evidence to support it.
But if you introduce just a tiny bit of reason, the pre-biotic "primordial soup" wouldn't have just one each of the necessary molecules to begin life. The soup would have literally trillions of possible combinations when the correct conditions for life "arrived". The only miracle of life is if it HADN'T happened.

But for some reason we cannot simulate the conditions and make even one such molecule happen in pre-biotic conditions.
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Re: Calculating the Odds of life

Postby tentative » Wed Dec 22, 2010 12:02 pm

Ganapati wrote:
tentative wrote:Coming in late on this, but... The ID game of numbers assumes one single instance of the right combination of molecules necessary to form self-replicating life. The numbers look overwhelmingly in favor of ID.

It is funny that those who believe in abiogenesis think the only reason it can be rejected is because someone is proposing an alternate hypothesis based on Intelligent Design. Any hypothesis can be rejected without proposing an alternate hypothesis either because the proposed hypothesis is not falsifiable and hence not scientific or because there isn't enough evidence to support it.
But if you introduce just a tiny bit of reason, the pre-biotic "primordial soup" wouldn't have just one each of the necessary molecules to begin life. The soup would have literally trillions of possible combinations when the correct conditions for life "arrived". The only miracle of life is if it HADN'T happened.

But for some reason we cannot simulate the conditions and make even one such molecule happen in pre-biotic conditions.

The numbers game used in the OP... What would be the purpose if not to discredit abiogenesis as possible? Gee, I wonder what the agenda behind those numbers might be? :roll: But if numbers used "scientifically" is useful, consider the potential opportunities given all the waters in all the oceans on the planet. The possible opportunities for abiogenesis to occur when conditions are right for self replicating life to appear is staggering. Why have all our efforts to replicate those conditions and create life failed? Experiments involving whole oceans and conducted over the period of a million years or so are a bit difficult to put together at this time. But you are right. Abiogenesis is just an unproven hypothesis and will likely remain such given the sheer magnitude of the necessary proofs. Still, failed experiments in a bathtub says nothing about an ocean. Yes, just a hypothesis, but it beats the hell out of anything else offered as explanation.
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Re: Calculating the Odds of life

Postby Ganapati » Wed Dec 22, 2010 12:54 pm

tentative wrote:The numbers game used in the OP... What would be the purpose if not to discredit abiogenesis as possible? Gee, I wonder what the agenda behind those numbers might be? :roll: But if numbers used "scientifically" is useful, consider the potential opportunities given all the waters in all the oceans on the planet. The possible opportunities for abiogenesis to occur when conditions are right for self replicating life to appear is staggering. Why have all our efforts to replicate those conditions and create life failed? Experiments involving whole oceans and conducted over the period of a million years or so are a bit difficult to put together at this time. But you are right. Abiogenesis is just an unproven hypothesis and will likely remain such given the sheer magnitude of the necessary proofs. Still, failed experiments in a bathtub says nothing about an ocean. Yes, just a hypothesis, but it beats the hell out of anything else offered as explanation.

I am not so convinced about this "The possible opportunities for abiogenesis to occur when conditions are right for self replicating life to appear is staggering". Until someone rigorously calculates the opportunities to claim one way or the other is meaningless. However the fact that none of the supporters of abiogenesis, including scientists, actually come out with any rigorous numbers is highly suspcicious in itself.
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Re: Calculating the Odds of life

Postby tentative » Wed Dec 22, 2010 7:32 pm

Ganapati wrote:
tentative wrote:The numbers game used in the OP... What would be the purpose if not to discredit abiogenesis as possible? Gee, I wonder what the agenda behind those numbers might be? :roll: But if numbers used "scientifically" is useful, consider the potential opportunities given all the waters in all the oceans on the planet. The possible opportunities for abiogenesis to occur when conditions are right for self replicating life to appear is staggering. Why have all our efforts to replicate those conditions and create life failed? Experiments involving whole oceans and conducted over the period of a million years or so are a bit difficult to put together at this time. But you are right. Abiogenesis is just an unproven hypothesis and will likely remain such given the sheer magnitude of the necessary proofs. Still, failed experiments in a bathtub says nothing about an ocean. Yes, just a hypothesis, but it beats the hell out of anything else offered as explanation.

I am not so convinced about this "The possible opportunities for abiogenesis to occur when conditions are right for self replicating life to appear is staggering". Until someone rigorously calculates the opportunities to claim one way or the other is meaningless. However the fact that none of the supporters of abiogenesis, including scientists, actually come out with any rigorous numbers is highly suspcicious in itself.
Ummm, reason alone suggests that the numbers game is bogus regardless the hypothesis. Any competent scientist isn't about to proclaim "rigorous" numbers. At best, the number is "large". the question isn't the numbers, it is the plausibility of the hypothesis matching up with what little we know. If one examines carefully the processes of early evolution of self replicating life forms, it isn't too difficult to suggest that that those processes had earlier precedents in the pre-biotic world. It seems more likely that abiogenesis is a bit more possible than a big guy in the sky.

We haven't yet come to full undestanding of all the potential "ingredients" of our pre-biotic environment - both in the oceans and atmosphere. We know a little, but certainly not a lot. But the default position of ID simply because we don't know is bogus. I would be highly suspicious of anyone declaring "rigorous numbers". As we learn more, perhaps numbers will have more credibility, but at this point, it is simply choosing which hypothesis seems more likely.
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