In a separate forum the origin of life came up again and I made the statement that there is not sufficient empirical evidence to accept abiogenesis as an established scientific fact. It was countered that there absolutely is, and that it is guaranteed in a sufficiently large universe. In my reply, I felt for the first time I was able to clearly crystallize the problems not only with this argument, but any claim that abiogenesis is a scientific fact, so I thought I would post my reply.
***It doesn't matter how big the universe is, if the universe isn't playing the game***
I'm speaking of *empirical demonstration/confirmation*
Naturalistic science has a superb track record (true). So we would expect unsolved problems to eventually find naturalistic explanations (true). The existence of life does not contradict the laws of physics (true). So it seems reasonable a priori to (think, believe, expect, infer) that the origin of life is also a result of naturalistic processes (sure, let's go with that; based on just the aforementioned, true). So then we look to science to confirm this (belief, expectation, inference), and usually find it. Have we found it for the origin of life? NO. We do not have empirical demonstration/confirmation of abiogenesis. A "scientific fact" typically requires repeated empirical demonstration/confirmation. So, it would be false to say abiogenesis is an established scientific fact. Answering, "no," does not "require saying there is something beyond science that intervenes in our physical universe in a remarkable way." Answering, "no," is an evidentiary statement, not a metaphysical one. It doesn't matter whether there is intervention or not. It does not change the fact that we do not have empirical demonstration/confirmation of abiogenesis, so we cannot say abiogenesis is an established scientific fact.
***The existence of life does not contradict the laws of physics, but it also does not seem explainable by them***
As you know, in science there are two main philosophical views concerning the origin of life: that it is the result of *chance* or *necessity*. That life is either the result of an astronomically improbable 'accident' and stroke of 'luck' (and thus, we would expect life to be an extremely rare, possibly one time occurrence in the universe); or, that life is the result of necessity (determinism), and an inevitable result of the laws of nature that can't *not* happen (and thus, we would expect the universe to be teeming with life). Of the two, chance is less of a scientific explanation (when it comes to combinatorial chemistry), than a 'Hail Mary' fall-back. If life is the result of natural causes, then we would expect it to be the "natural" result of the regularities ("laws") of nature. We would expect there to be some normal, natural process or phenomenon that occurs with regularity as a result of the laws of physics that leads to life, and that we can observe and study. Similar to stellar nucleosynthesis, and how we can observe and study the origin and evolution of stars, and origin and synthesis of the chemical elements inside those stars. But instead, we see no observational or empirical evidence of any kind that life is a "natural" occurrence---a normal, "natural" result of natural processes, phenomena, or the regularities of nature. Pier Luisi states it even more pointedly:
***Chance is less of a scientific explanation, than a 'Hail Mary' fall back***
"Life is not a thermodynamic spontaneous process. In other terms, we can say that the origin of life is not deterministic." So that leaves our "chance" fall back, which is problematic from the start, because we're already conceding that life is not the result of normal, natural processes, phenomena or regularities ("laws") of nature (Which is the whole basis of scientific study!). We're conceding that there is nothing "natural" about life, and that it is a chance 'accident.' But let's consider this anyway. The simplest known cells still contain around 300 genes (and proteins), and thousands of copies of each protein, along with fatty acids, sugars, etc. totaling around a million or so molecules that are crowded and compartmentalized into a one cubic micrometer volume. It is a highly sophisticated, integrated, self-referential, causally looped, autopoietic system that creates and replaces its own component parts, and that at minimum requires integrated compartmentalization, metabolism, and self-replication. Abiotically, we are NOWHERE close to getting this. We don't even know how to get to it "on paper." Like Luisi says, "we do not have a conceivable theoretical scheme on paper, on how the origin of life may have come about. We can't even get ONE, SINGLE, ordered, functional protein or nucleic acid (RNA). But let's look at getting a single protein (which of the two, would be the "easiest" to do, even though most still consider this a dead-end).
If we imagine ourselves a "warm little pond" with the "right conditions" for amino acid synthesis and assembly into a protein/polypeptide that is well stocked with a limitless supply of our 20 different amino acids, so we can roll the dice, and randomly combine our amino acids in the 'Hail Mary' hope that we hit upon a correct, linear, ordered sequence of amino acids to give us a functional protein (lets say, 100 amino acids long). We could do the typical crude calculation: 1/2 chance of picking the correct isomer ("left-handed" amino acid) x 1/4 chance of correct peptide bond formation x 1/2 conservative chance of picking the correct amino acid (polar or nonpolar), gives us 1/2 x 1/4 x 1/2 = 1/16 chance of getting a 'correct' amino acid, which each roll of the dice. The chance of doing that 100 times in a row is (1/16)^100 = 1 chance in 10^121; i.e., the number 1 with 121 zeros after it, which is so astronomically large, compared to your "1 chance in 1 billion (10^9)" lottery example, and even the age of our universe in seconds (10^17). Yes, it's crude and imprecise, and there are a ton of things wrong with it, but it gives us a rough sense of the "chance" probability involved. And that's just for one, single protein.
*But you see, even if we started with a complete, intact, whole cell that was alive just moments ago, we can still predict that barring some interference and ingenuity on our part that it will not reanimate itself. We can predict *empirically* by the laws of physics and chemistry that the intact cell will simply degrade, and decompose back down into its component parts *in accordance* with the regularities ("laws") of nature. The same degradative *natural processes* that are at work against such an intact cell reanimating are also working against those components coming together in the first place. There is a name for this....
***The "Tar/Asphalt Paradox"***
The "Tar/Asphalt Paradox" is not some theoretical problem, but a real-world problem that is well-known in the origin of life field that is backed by an "enormous amount of empirical data":
BUT, what about your argument that a sufficiently large universe solves everything and makes the seemingly impossible, not simply possible, but *guaranteed*? Well, first, that's not really a scientific explanation. It doesn't really explain anything. It doesn't solve the "Tar/Asphalt Paradox." But there's another problem...
For the better part of a year, I have done a deep dive into this topic, and researched it more extensively than I ever have. The myriad problems with abiogenesis are no secret and I thought I was well-versed. But I was unprepared for what I discovered. I expected to find more of the same. But instead I was "shocked" to learn of problems that I thought we had already solved. Assembling a chain of monomer 'building blocks' like amino acids to form a polymer is always a difficult challenge, but still there is *empirical demonstration* that it can be done. So this would seem to justify our "warm little pond" game-of-chance for spontaneously assembling a polypeptide from our limitless stock of 20 amino acids. And I was aware of hundreds of experimental studies that demonstrate amino acids (and nucleotides) can be chained together to make polymer peptide (or polynucleotide) chains on the surfaces of clay, by volcanic gas (carbonyl sulfide), and so on. But I had never taken a close look at them; never taken a deep look at the primary sources, until this past year. And as it turns out, I discovered that just like the lab-created self-replicating systems, these studies are also "proof of concept/principle" experiments, and simply *models* for prebiotic polymer synthesis (and this includes both polypeptides and polynucleotides).
In short, there is no such thing as the 20 amino acids randomly combining together by chance to make peptides as envisioned by our "warm little pond" thought experiment. The spontaneous, chance formation of a functional protein from a random pool of 20 amino acids is impossible, because the scenario itself is a figment of the imagination (the problems are even worse for nucleotides!). There is no such environment where the 20 amino acids can randomly combine so we can play our roll-the-dice games of chance. The unique chemical properties of amino acid side chains make it impossible. Different amino acids have different reactivities, and are reactive under different sets of environmental conditions, temperatures, pH, salt concentrations, and so on.
At best, our lab experiments under ideal conditions typically produce short-length peptides of only 2-3 amino acids for co-/hetero-peptides containing only 2-3 different types of amino acids, or up to ~10 amino acids for homopeptides made of a single type of amino acid (usually the simplest amino acid, glycine) (and the longer the peptide, the smaller the % yield).
You see, when people read press releases about 'breakthroughs' on the origin of life and how they've discovered that amino acids can assemble into peptides, they envision the 20 amino acids randomly combining together to make polymer chains and think if you just roll-the-dice enough times, 'Voila!' we get life. They don't realize these studies are only *models* of prebiotic polymerization involving a single type of amino acid up to a few that is only a few amino acids long. We have models only, and no empiriclal evidence that nature can even play our roll-the-dice game of chance.
(The prebiotic polymers we can form)
And this is comparable to what we find in nature (although, the lab experiments still outperform nature). For example, in meteorites like the Murchison meteorite there are organic compounds---most of them useless---but a tiny percent (~1-2%) of potentially useful amino acids, sugars, and nucleotides. In fact, the types of organic compounds we find in meteorites, matches what we see in prebiotic experiments like the famous Stanley Miller experiment. But in rare cases, some of these meteorites also contain miniscule traces of short-length peptides; especially dipeptides of glycine (2 amino acids of glycine connected together). These comprise about 0.001% of the organic content, which is comparable to what we'd predict based on our experimental results.
You see, everyone envisions the origin of life as a simple game of roll-the-dice and if we roll the dice enough times (in a big enough universe) we're guaranteed to hit the jackpot. No matter how improbable the random assembly of a protein (or RNA) from our pool of 20 amino acids, in a sufficiently large universe, it's bound to happen. But we're playing in an imaginary pool. There is no such thing as a "warm little pond" (or any known environment in nature or the lab!) where our 20 amino acids (or even just 10!) are capable of chaining together in random combinations due to their varied, mutually exclusive chemical reactivities (i.e., different amino acids are reactive at different pH, temp, salt concentration, etc., and inhibited or destroyed in others). The experimental evidence shows us that amino acids can readily form in small yields (~1-2%). But at best, the experimental evidence indicates that only two or three (in rare cases, four) different types of amino acids can chain together, and typically in lengths of only 2-3 amino acids long (up to ~10 for a single type of amino acid like glycine). And this experimental evidence matches our observational evidence of relatively small percent yields of amino acids, and even smaller, trace amounts of diamino acids in nature.
As my wife likes to remind me when I get excited about how big a lottery jackpot has grown between winnings, "You have to play the lottery to win. You have to buy a ticket" (which, I don't think we've ever done).
We see the same problem with abiogenesis: the laws of nature do not inevitably lead to life, but, in fact, work against it; the odds are astronomically improbable in our game-of-chance just for ONE single functional protein or RNA (and the odds for life itself are incalculable); we don't even know how it could happen in theory "on paper," and can't even conceive of a way for it to happen; and we don't have any empirical evidence that nature is even trying to play the game (or is even capable of playing). So...
***It doesn't matter how big the universe is, if the universe isn't playing the game (and so far nature is a 'no show' at the card table)***
***So do we have empirical demonstration/confirmation of abiogenesis? NO***
***Can we state that abiogenesis is an established scientific fact? NO***