The Nature of Consciousness

Piero Scaruffi

(Copyright © 2013 Piero Scaruffi | Legal restrictions )
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These are excerpts and elaborations from my book "The Nature of Consciousness"

Necessity

If Monod thought that life was highly improbable and happened only by chance, the US biologist Harold Morowitz believes that life occurred so early in the history of the planet because it was highly probable.

Based on the chemistry of living matter, Morowitz argued that the simplest living cell that can exhibit growth and replication must be a "bilayer vesicle" made of "amphiphiles" (a class of molecules, that includes, for example, fatty acids). Such a vesicle, thermodynamically speaking, represents a "local minimum" of free energy, and that means that it is a structure that is likely to emerge spontaneously.  The bilayers spontaneously form closed vesicles. The closure (the membrane) led to the physical and chemical separation of the organism from the environment. This is, for Morowitz, the crucial event in the early evolution of life.  Later, these vesicles may have incorporated enzymes as catalysts and all the other machinery of life.  These vesicles are the "protocells" from which modern cells evolved.

In other words, Morowitz believes that first came membranes: first membranes arose, then RNA, DNA or proteins or something else originated life. First of all an organism has a border that differentiates it from the environment, that isolates it thermodynamically, that bestows it an identity, that enables metabolism. The second step is to survive: the membrane's content (the cell) must be able to interact with the environment in such a way that it persists. Then the cell can acquire RNA or DNA or whatever else and reproduce and evolve and so forth.

All of this happened not by chance, but because it was very likely to happen. It was written in the laws of Physics and Chemistry.

Furthermore, Martin Eigen refuted Monod's thesis by showing that natural selection is not blind. Eigen agrees with Monod that information emerges from random fluctuations (from chance), but he thinks that evolution does not act blindly. Evolution is driven by an internal feedback mechanism that searches for the best route to optimal performance.

Eigen found that the distribution of variants is asymmetric, and tends to favor the "best" variants (from a survival point of view). Life seems to know where to look for best variants. As a matter of fact, Eigen discovered a feedback mechanism, inherent in natural selection, that favors (or accelerates the search for) superior variants.  Selection is not blind because it is driven by this internal feedback mechanism. Evolution is inherently biased towards the "best" possible solution to the survival problem, and this creates the illusion of the goal-directedness of evolution.

Evolution is "directed" towards optimization of functional efficiency.

Where Monod thinks that (biological) information arises from non-information by sheer luck, Eigen thinks that a fundamental law drives non-information towards information.

 


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