Calculating the Odds of life

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Re: Calculating the Odds of life

Postby Ganapati » Thu Dec 23, 2010 7:48 am

tentative wrote:
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.

If we don't know anything about numbers how does anyone say it is "large" or "likely"?

So it is simply matter of what appeals to the individual in question, whether appearance of life can be expected from the currently known principles or not. There is nothing more to it. Intelligent Design is not falsifiable and hence not scientific. What makes abiogenesis falsifiable and hence scientific? Either of them can be proven, but neither can be disproved. Precisely the reason why I called abiogenesis a faith position. That it comes from "scientific-minded" people doesn't make it less so.
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Re: Calculating the Odds of life

Postby Xunzian » Thu Dec 30, 2010 11:36 pm

Ganapati wrote: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.


See below. Goal-post moved!

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).


I don't know where you are going with this one. Coherent narratives provide vehicles for discovery, that is how they operate. When problems are identified within them, the narrative changes but knowledge progresses either way.

Pretending omniscience is not science and offering a narrative that validates such pretentions isn't a merit in itself.


Ahhh, that is where you are going with it: straight into character-assassination. Ad-hom arguments are usually considered a tactic of desperation.

You perhaps never saw the goal post. Where did you assume it was?


Ganapati wrote: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.


What I've provided meets those criteria, but now it is all about whether or not abiogenesis has been conclusively proven (which we all know it hasn't). Seems to me like a rather drastic shift in goal-posts.

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.


So what are you ever-changing minimum conditions at the moment? Oh, and there was some more character assassination in that part too. As I've been saying, you've got to be careful with these rhetorical devices. They harm your argument more than they help it.

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


From ad hom to strawman. Running the gamut of rhetorical devices here . . .

Can you let me know how abiogenesis is falsifiable?


The RNA-world hypothesis I've described here is falsifiable in the following ways:

1) If any of the components were unable to form in significant quantities under pre-biotic conditions.
2) If any of the components were highly unstable under pre-biotic conditions.
3) If ribozymes were unable to have autocatalytic nucleotide polymerase activity.
4) If the size of self-replicating ribozymes were larger than can be (reasonably) expected to form under pre-biotic conditions.
5) If viral taxonomy demonstrates that viruses came about after nucleotide encapsulation.

Probably some other ways, but those are off the top of my head.
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Re: Calculating the Odds of life

Postby Ganapati » Fri Dec 31, 2010 10:23 am

Xunzian wrote:
Ganapati wrote: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.


What I've provided meets those criteria, but now it is all about whether or not abiogenesis has been conclusively proven (which we all know it hasn't). Seems to me like a rather drastic shift in goal-posts.

Apparently only in your mind. What are the intermediate molecules that lead to your 165nt self-replicating molecule? Have the environments they are capable of forming been demonstrated? Has such progression of environments been demonstrated as what can be expected from laws of physics?

Or are you claiming that the nucleotides are themselves the intermediate molecules and the first self-replicating molecule appeared as one of a random combination of nucleotides? Has the environment it is capable of forming from a collection of single nucleotides been demonstrated? If that is your position, it shouldn't be difficult for you to compute the probability of that happening and letting us know.

That some non-self-replicating molecules capable of forming in an pre-biotic environment are longer than the shortest self-replicating molecule (that has not been proven to form in a pre-biotic environment) means as much as the existence of a mountain taller than Mount Rushmore does to the hypothesis of erosion causing the faces on Mount Rushmore does, which is nothing.
Can you let me know how abiogenesis is falsifiable?


The RNA-world hypothesis I've described here is falsifiable in the following ways:

1) If any of the components were unable to form in significant quantities under pre-biotic conditions.
2) If any of the components were highly unstable under pre-biotic conditions.
3) If ribozymes were unable to have autocatalytic nucleotide polymerase activity.
4) If the size of self-replicating ribozymes were larger than can be (reasonably) expected to form under pre-biotic conditions.
5) If viral taxonomy demonstrates that viruses came about after nucleotide encapsulation.

Probably some other ways, but those are off the top of my head.

ID is falsifiable by demonstraing that life formed in pre-biotic conditions and hence that becomes a scientific hypothesis too :roll: Not sure if you understand what falsifiability means.
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Re: Calculating the Odds of life

Postby Xunzian » Mon Jan 03, 2011 12:05 pm

Ganapati wrote:Apparently only in your mind. What are the intermediate molecules that lead to your 165nt self-replicating molecule? Have the environments they are capable of forming been demonstrated? Has such progression of environments been demonstrated as what can be expected from laws of physics?


Yes.

See the papers I provided earlier.

Or are you claiming that the nucleotides are themselves the intermediate molecules and the first self-replicating molecule appeared as one of a random combination of nucleotides? Has the environment it is capable of forming from a collection of single nucleotides been demonstrated? If that is your position, it shouldn't be difficult for you to compute the probability of that happening and letting us know.


Yes.

See the experiments I listed earlier.


That some non-self-replicating molecules capable of forming in an pre-biotic environment are longer than the shortest self-replicating molecule (that has not been proven to form in a pre-biotic environment) means as much as the existence of a mountain taller than Mount Rushmore does to the hypothesis of erosion causing the faces on Mount Rushmore does, which is nothing.


Spurious comparison coupled with an argument from ignorance (an informal fallacy).

ID is falsifiable by demonstraing that life formed in pre-biotic conditions and hence that becomes a scientific hypothesis too :roll: Not sure if you understand what falsifiability means.


More ad homs? I'm beginning to think that represents the totality of your argument.

See, the way falsifiability works is that you set up experiments seeking to disprove the hypothesis. If any of those that I listed acted in a manner counter to the RNA world hypothesis, that would eliminate the RNA world hypothesis from the running.

You are really backing yourself into a corner here.
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Re: Calculating the Odds of life

Postby Ganapati » Mon Jan 03, 2011 12:09 pm

OK. I give up, since you haven't provided what you claim to. If someone else thinks you are actually making sense, he can have a discussion with you, because I cannot have a discussion with someone where the only evidence exists in his mind.

PS: There is nothing in the papers to support your claim.
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