Show me the metabolism! Part One.

Being some comments on ‘The Origins of Order: Self-Organization and Selection in Evolution’, by Stuart A. Kauffman.

I thought I would expand my central criticism of Kauffman’s model a bit in the hope of clarifying what I was saying and starting a fruitful discussion.

My thesis is that the network of catalytic polymers and substrates that Kauffman postulates as an initial self-organising complex system which can give rise to more lifelike systems is so inordinately complex and unlikely that it in no way addresses the crucial problem of the origin of life.

Specifically, what is first needed is not a mechanism for self-replication and complexification, but a plausible metabolism enabling some tiny corner of the universe to dump entropy outside itself and accumulate order within.

My initial statement of the thesis:

Marco sometimes has to contend with people who find the evolutionary transition monkey → man as implausible as the transition unlife → life. If I were arguing with one of those people, then a clear exposition of how a ‘primordial protoplasmic globule’ (PPG) might have unfolded into the bewildering variety of life we know on Earth today might be of value. In the 19th century, or in the darker corners of the 21st century, a layman might suppose a PPG simple enough to have arisen spontaneously. For such a layman, an exposition of the pageant of evolution from the PPG to the diverse biosphere we see around us might seem to be a complete materialist description of the history of life.

To the biologist, this pageant is far from a complete description. The biologist knows the complexity of the prokaryote, the PPG, and finds the unfolding of its descendants almost trivial. The PPG is not the simple explanation: it is the complicated thing that needs to be explained.

In a similar way, to the chemist, the unfolding of Kauffman’s ‘complex system of catalytic polymers’ (CSCP) to give rise to something recognisable as life seems almost trivial. The CSCP is the complicated thing that needs to be explained.

Kauffman’s statement: ‘the origin of life, rather than being vastly improbable, is instead an expected collective property of a complex system of catalytic polymers and the molecules on which they act’ should become: ‘the origin of life, rather than being vastly improbable, is instead an expected collective property of a vastly improbable complex system of catalytic polymers and the molecules on which they act’.

I do not think I am alone here. I think if you were to show Kauffman’s system to any chemist anywhere in the world, there is a 99% probability they would find it unsatisfactory. Not because such a system could not exist, but because ‘it just happened’ is an entirely implausible explanation for its existence. Saying 'it just happened' is hardly more satisfactory than pointing at a functioning cell and saying 'it just happened'. (The remaining 1% would be those who have a quasi-religious faith in the self-organising properties of matter.)

Any chemist would ask: 'What is driving this cycle of reactions? Where is the energy coming from? What is preventing this system from dissipating?'

There is no such thing as 'Order for Free'. That is the Law. If you want order at point A, you need to dump your disorder at points not-A. Should anyone claim there is such a thing as 'Order for Free', let them be unto you even as the homeopaths and the creationists.