JTW's Evolutionary Origins - Author: Wachtershauser, Gunter

The Scientific Merit of the Theory

"[I]t would be preposterous to assume that these first attempts at retrodiction are likely to hit upon the true historic sequence of events.

The scientific merit of such a theory of biochemical evolution is its fertility in producing increasingly comprehensive and powerful explanations.

Ultimately, the progressive amendments of the theory, guided by methodological postulates and by experimental tests, should lead to a correlation of the various lines of pathway evolution with each other and with the appearance of enzymes: in short,

a historically ordered table of biochemistry.

I expect that this may be a precondition for making significant progress in the evolutionary explanation of [the] genetic machinery, the genetic code and the process of translation."

"Progress in science is in my opinion crucially dependent on the methodological efforts and ultimately on the theory of knowledge.

Of course, a scientist holding the wrong theory of knowledge can still have extraodinary achievements in his field; other scientists, subscribing to the right theory of knowledge, may still be barren.

Yet it seems to be clear to me that an unsound methodology tends to be a hinderance while sound methodological reflections tend to be helpful.

The methodology of the present investigation is wholly indebted to the epistemology of Karl R. Popper and notably to the three central tenets of his philosopy:"

• The rejection of inductivism (Popper, 1959, 1963, 1972, 1979, 1983b) frees us from the illusionary commitment that we should induce a general theory from the incidentally obtained or known particulars.
  
  Instead, we can not treat the body of known particulars as constituting the central part of our problem of explanation.
  
  
• The rejection of reductionism (Popper, 1972, 1974) frees us from the imagined task to derive biology from chemistry.
  
  It opens our eyes to the fact that the problem of an evolutionary theory of biochemistry is a biological problem, ant that its solution will be a biological theory.
  
  The laws of chemistry are basic of course, yet ancillary; and they are so in two ways.
  
  The known law of chemistry are welcome restrictions on the chaos of biological possibilities.
  
  But so far unknown universal laws of chemistry are also needed and some of them indeed entailed by the biological theory presented here [Wachtershauser, 1992].
  
  They form the basis for new kinds of experiments, exposing the theory to crucial tests and potential refutation.
  
  
• Abandoning determinism (Popper, 1972, 1974, 1983c, 1990a) we come to see that chemical reality covers more than high-propensity ("deterministic") reactions.
  
  In fact, low-propensity ignitions seem to be the very chemical stuff of biochemical evolution.
  
  Admittedly, present biochemistry is largely concerned with the study of deterministic processes.
  
  But it seems to me that ignitions of new autocatalytic cycles, (i.e. mutations), tend to go beyond deterministic chemistry and increasingly so with progessing evolution, which means that biochemical evolution cannot be properly appreciated within a deterministic framework.
  
  

"According to Popper's (1959, 1963, 1972, 1979, 1983b) methodology of science, it is the aim of a scientific theory to predict and to explain.

And alternative theories compete for the greatest predictive power (testability) and for the greatest explanatory power - for explaining the most facts with the fewest assumptions.

A theory on the origin of life is scientific to the extent that it satisfies these aims.

When we explain, we reduce known facts to unknown theoretical entities (Popper, 1963);

known reaction products to an unknown reaction mechanism or to unknown intermediates;

Known extant organisms to unknown missing links; known biochemical pathways to an unknown origin of life.

Chemically speaking, an evolutionary explanation of todays life by a hypothetical origin means the treatment of evolution as a gigantic reaction mechanism, stretching over some four billion years with myriads of reaction intermediates.

Biologically speaking, such evolutionary explanation means to draw lines of descent from the extant organisms back towards the first reproducing metabolist.

Both approaches emphasize different aspects of the same overall process. The chemical approach emphasizes individual reations within a metabolism..

But it tends to fail with unstable changeover from one stable metabolism to another stable metabolism.

The biological approach emphasizes the sequence of changeovers and it tends to take a whole organism (metabolist) as its smallest unit.

My theory on the chemo-autotrophic origin and early evolution of life combines both approaches: by postulating a primordial organism which is characterized in chemical terms, and by drawing evolutionary linkages to extant organisms.

In order to bring out best the explanatory power of the theory (plurality of explained facts and paucity of explaining assumptions) it is presented in a deductive format with few independent postulates and many derived theorems.

It is important to note, however, that such derivations will have to make extensive use of a large body of background knowledge in the fields of organic, inorganic, and physical chemistry as well as geochemistry.

• Wachtershauser, Gunter
  • Groundworks for an Evolutionary Biochemistry: The Iron-Sulphur World
  • Progress in Biophysics and Molecular Biology: Vol. 58, No. 2, pp.85-202
  • 1992
  • [Pubmed]

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