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DSimon comments on Something's Wrong - Less Wrong
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And that claim by you is based on ... what exactly? Experiments you have performed? Books you have read explaining the theory to your satisfaction with no obvious hand waving? Books like the ones we all have read describing Darwin's theory of evolution through natural selection? Or maybe you have encountered a section in a library filled with technical material beyond your comprehension, but which you are pretty sure you could comprehend with enough effort? For me, something in this category would be stereo amplifiers - I've seen the books so I know there is nothing supernatural involved, though I can't explain it myself.
From what you write below, I'm guessing your background puts you at roughly this level regarding abiogenesis. Except, the difference is that there is no library section filled with technical material explaining how life originated from non-life. So, I think you are going on faith.
No there aren't. There is not a single plausible theory in existence right now claiming that life originates from amino acids arising from a Miller-Urey type of process. There are no chemically sound models for creating life from Miller-Urey building blocks.
There are some models which have life starting with RNA, and some which have life starting with lipids, or iron-sulfide minerals or even (pace Tim) starting with clay. But you didn't mention those more recent and plausible theories. Instead you went on faith.
No. Not at all. I don't have a clue as to what it would even mean to look for, let alone investigate a non-naturalistic hypothesis.
What I am saying is this: Suppose I have before me a theist who claims that a Deity must have been the cause of the Big Bang. "Something from nothing" and all that. Suppose further that my own version of atheism is so completely non-evangelical and my knowledge of cosmology so weak that I say to him, "Could be! I don't believe that a Deity was involved, but I don't have any evidence to rule it out."
So that is the supposition. Next, suppose he says "Furthermore, I think the Deity must have been involved in the origin of life, back 3+ billion years ago. From what I know of chemistry and biochemistry, that could not have been spontaneous." I would tell him that I too know quite a bit about chemistry and biochemistry, and that there are many, many clues indicating that life based on RNA probably existed before modern life based on DNA and amino acids and proteins. There is strong evidence that life in its current form came from something more primitive.
Now, suppose he says "Yes, I understand all that evidence. But you still have no theory to explain how life based on RNA might have started. All you have is handwaving. My belief, since I already believe in a Creator-Deity for the Big Bang, is that a Creator-Deity was also involved in the origin of the RNA World." If he said that, then I would answer, "Ok, you can believe that, but since I don't already believe in a Creator Deity, I would prefer to believe that the first living organism on earth arose by some unknown natural process. In fact, I have some ideas as to how it might have happened."
Yes, I said "prefer to believe" this time. I don't have a good explanation for life's origin, though I have spent a good deal of my spare time over the past 30 years looking for one.
Thanks for catching me in this error. I was very vaguely familiar with those theories, but not enough to realize that they require source materials not available from Miller-Urey building blocks.
The problem I see is not so much with the source materials or "building blocks". It is putting them together into something that reproduces itself. When Miller performed his experiment, we had no idea how life worked at the mechanical level. Even amino acids seemed somehow magic. So when Miller showed they are not magic, it seemed like a big deal.
Now we know how life works mechanically. It is pretty complicated. It is difficult to imagine something much simpler that would still work. Putting the "building blocks" together in a way that works currently seems "uphill" thermodynamically and very much uphill in terms of information. IMHO, we are today farther from a solution than we thought we were back in 1953.
But, isn't the issue not only the amount of information required but also the amount of time and space that was available to work with?
To pick one scientific paper which I think summarizes what you're talking about, this paper discusses "[...][t]he implausibility of the suggestion that complicated cycles could self-organize, and the importance of learning more about the potential of surfaces to help organize simpler cycles[...]".
The chemistry discussed in that paper is well above my head, but I can still read it well enough to conclude that it seems to fallaciously arrive at probabilistic-sounding conclusions (i.e. "To postulate one fortuitously catalyzed reaction, perhaps catalyzed by a metal ion, might be reasonable, but to postulate a suite of them is to appeal to magic.") without actually doing any probability calculations. It's not enough to point out that the processes required to bootstrap a citric acid cycle are unlikely; how unlikely are they compared to the number of opportunities?
Am I missing something important? The above is my current understanding of the situation which I recognize to be low-level, and I present it primarily as an invitation for correction and edification, only secondarily as a counterargument to your claims.
It is important to realize that Orgel is a leader of one faction (I will resist the temptation to write "sect") and he is critiquing the ideas of a different faction. Since I happen to subscribe to the ideas of the second faction, I may not be perfectly fair to Orgel here.
Orgel does not calculate probabilities in part because the ideas he is critiquing are not specific enough to permit such a calculation. Furthermore, and this is something you would need some background to appreciate, the issue here isn't a question of a fluke coming together somewhere here on earth of the right ingredients. It is more a matter of a fluke coming together of laws of chemistry. Orgel is saying that he doubts that the cycle idea would work anywhere in this universe - it would take a suspiciously fine-tuned universe to let all those reactions work together like that. It is a reasonable argument - particularly coming from someone whose chemical intuition is as good as Orgel's.
I think Orgel is pretty much right. The reductive citric acid cycle is a cute idea as the core of a metabolism-first theory, but it is probably too big and complicated a cycle to be realistic as the first cycle. Personally, I think that something simpler, using CO or HCN as the carbon source has a better chance of success. But until we come up with something specific and testable, the "metabolism first" faction maybe deserves Orgel's scorn. The annoying thing is that our best ideas are untestable because they require enormous pressures and unsafe ingredients to test them. Damned frustrating when you want to criticize the other side for producing untestable theories.
Orgel was fair to the extent that he also provided a pretty good critiqueto his own faction's ideas at about the same time. But it is possible that Sutherland's new ideas on RNA synthesis may revive the RNA-first viewpoint.
If you really dig watching abiogenesis research, as I do, it is an exciting time to be alive. Lots of ideas, something wrong with every one of them, but sooner or later we are bound to figure it all out.