"Kauffman is chiefly concerned with reproduction as the defining feature of life. He makes only a superficial discussion of metabolism that does not consider its central thermodynamic requirements. But ultimately, metabolism is what is most important."
This reminded me of an "alien life" forum that was discussing, among other things, how we would recognise life as we don't know it. There was a consensus that at a minimum, reproduction AND metabolism would need to be observed. However, when we are talking about abiogenesis, the conundrum is more about how they have to simultaneously come about. Meaningful reproduction is impossible without metabolism to generate the work energy that reproduces something. Metabolism is pretty useless if the system that metabolises is a one off that cannot be reproduced faithfully and it's important features "locked away" for future use. The blueprint of "the system" doesn't need metabolism to exist, it needs metabolism to perform work and reproduce.
"Without petrol, the most splendidly engineered automobile will just sit there. Without a plausible metabolism, the most elegant net of autocatalytic reactions is an empty exercise in symbol manipulation."
Why can't a car be considered a living thing for the purpose of this exercise? For that matter why can't a primitive stone axe head? They perform work and can be reproduced. The system graph and energy transfers is what is important in defining what metabolism and reproduction is, not our experience of how extremely complex things that we have studied intimately perform these same system graph characteristics. Thus things like, "mass flux", "high energy flux", "vesicles", "Proto-metabolism" etc. are not particular requirements when talking about the "system" before life as we know it. The energy graph is important for when metabolism is occurring, and that the system is locked away with reproducible features when the energy/reactants source is depleted. Thus if an axe head lies in the ground undisturbed for millions of years, it would be easy to reproduce. If it was being constantly bombarded by energy flux, ie. people using it, it would just wear away until it was no longer useful. Thus, an extremely encapsulated system, with persistent, naturally reproducible features is more relevant than looking at the amount of energy flux a motorcar needs to keep going, and applying it to the needs of an axe head.
"(1) Through a long and complicated process of prebiotic development containing all the most interesting parts of the story of the origin of life.
(2) As a system created by someone or something.
I don’t intend this as an argument in favour of intelligent design [see definition 1], still less of Intelligent Design [see definition 2]. Ockham’s razor suggests we should stick with explanation (1) unless we should find some very compelling evidence for (2). At any rate, the essential requirements of the pre-biotic processes leading to life based on the chemistry we know are going to be the same as the requirements of pre-biotic processes leading to life based on different chemistry."
Ockham s razor is a lie perpetrated by scientists to make out they have gnosis when they have none. Anyway, have you considered dust cloud life? Or plasma physics life?
We don't know that life that could create chemical life is based on chemistry. We have no gnosis on the requirements of life that may have generated biochemical life through an evolutionary prebiotic process of design. All we have is human experience of design as an evolutionary process with intelligent input. The intelligence is not enough to design something complicated from scratch, and thus the sequence of precedents from transistor to computer may be accessible to historians a million years into the future. Equally, whether intelligently designed or not, we should have confidence in the possibility of precedent biological life "designs" for us to discover.
"What I am arguing is that both the ‘RNA world’ and the ‘Protein world’ are historically late phenomena, and that the critical events for the origin of life lie much deeper."
I absolutely agree with this.
"There is no reason to expect that living systems today preserve the same chemistry of the first living systems. "
I absolutely *disagree* with this. Evolution and evolutionary design processes build on what is known to work. No point changing from silicon to something else.