Before our investigation into abiogenesis was terminated by the raising of the fallacy of the quantizing the continuum (unwillingness of correspondents to accept there could be a definition of life v non-life/death)
That wasn't the reason for the raising of the fallacy, nor were the participants in that thread "unwilling to accept" that there could be a definition of life vs non-life. The disagreement was over whether there were graduated states in between.
- we did explore the thermal vents speculation and discovered that the newer preference is primordial pizza (over primordial soup).
The "primordial pizza" is a slang term *for* the hydrothermal vent scenario. Here you make it sound as if one has replaced the other, when in fact they are the same thing. Or have I misunderstood/missed your point here?
[speaking of the Urey-Miller experiments being repeated with success] But the Earth's early atmosphere is nowadays thought to be neutral, consisting mostly of nitrogen and carbon dioxide, instead of hydrogen, ammonia, and methane (reducing), as had been suggested from cosmochemical grounds. Urey-Miller experiments performed with a neutral mixture are much less successful than those with a reducing mixture; however, the early Earth could easily have had reducing microenvironments, like hot springs and hydrothermal vents.
There is also the conundrum that bodies of water are poor places for the formation of biomolecules like proteins and nucleic acids, since the "primordial soup" is inevitably very dilute, making it difficult for molecules to "find" each other. This conundrum has led to the "primordial pizza" hypothesis of the origin of life on mineral surfaces like clay surfaces, which organic molecules can easily stick to, and which have catalytic properties that can easily assist in the formation of complex molecules. Günter Wächtershäuser has proposed that the Krebs Cycle (a.k.a. citric acid cycle, tricarboxylic acid cycle) had originated on such mineral surfaces, powered by iron-sulfur chemistry.
And while some biological molecules, like the smaller amino acids and nucleic-acid bases, are readily produced in Urey-Miller experiments, others, like sugars, are not. This means that nucleic acids are difficult to produce, since they contain the sugar ribose and its derivatives; this is a major difficulty with the otherwise-very-attractive "RNA world" hypothesis.
Thus, how to get from there to a complete self-reproducing system is still an unsolved problem, but this question is being actively researched.
Armen Y Mulkidjanian, Dmitry A Cherepanov, and Michael Y Galperin
Indeed, biochemical condensation reactions proceed with release of water, so that the presence of latter favors hydrolysis of biological polymers. Because of this feature, Bernal [27] and many researchers after him (as reviewed in ref. [10]) advanced the view that life has begun in tidal regions, so that condensation of primordial monomers proceeded under "fluctuating" conditions where the wet periods, enabling the exchange of reagents, alternated with dry ones, favoring the condensation reactions. The awareness of the potential danger of the UV damage, however, prompted other scientists to invoke a UV-protecting water layer (see e.g. ref. [19]), which apparently would impede the condensation reactions. More recently, several authors even moved the point of the life origin to the bottom of the ocean, where the reducing power of minerals and/or of hydrothermal vents was considered to be the energy source for the first condensation events [28,29]. It remained unexplained, though, how inorganic reductants could drive primordial condensation reactions in water in the absence of enzymes (see the discussion in refs. [30,31]).
In a sense, the absence of a consensus on a plausible mechanism for the origin and accumulation of the first RNA-like molecules has significantly hurt the development in the whole field and stimulated proliferation of the Panspermia hypothesis, not to mention various kinds of creationist ideas. It appears that our consideration of the UV irradiation as a positive, selective factor in primordial evolution may suggest a way out of the dead end. This view allows to place the cradle of life onto the sun-illuminated (semi) dry surface of the ancient Earth, as originally considered by Bernal [27]. Indeed, no other known energy source could compete with the UV component of the solar irradiation either in ability to serve simultaneously as both selective and driving force, or in continuity, strength, and access to the whole surface of Earth..
Multi-Phase Artificial Chemistry
The most accepted model for the origin of life has been proposed by [13,17] with the primordial ‘soup’. Hot deep sea vents as the birth place of life (the primordial ‘pizza’) were discussed as an interesting alternative [26. However, all these models need a prebiotic chemistry with complicated synthesis. As described in [20] and [21], they cannot occur in single, unpartitioned environment. A sequence of different environments would be important for the orgin of life, just as in the traditional organic synthesis. During such a synthesis a reaction mixture is subjected to certain conditions, then some products are extracted, purified, and/or crystallized, new reagents might be added, and the next step with new conditions begins. We can imagine an analogous situation in prebiotic chemistry, where the different conditions and steps are mimicked by different environments, i.e. phases like hot vents, the atmosphere, and ice, and intermittent evaporation, phase change, crystallization or filtration. This might mitigate the problems of complicated synthesis in prebiotic chemistry.
At post 643, I summarized the effect of the fallacy – i.e. that it kills any investigation of abiogenesis (non-life to life) by declining to quantize either term. Prior to the fallacy, an agreement had been reached on a definition – summarized at 491, agreed at 522.