Piero Scaruffi

These are excerpts and elaborations from my book "The Nature of Consciousness"

A Hierarchy of Lives  The reason why so many theories tend to identify the second law of Thermodynamics as the principal driving force of  biological order is that it is the only physical law that distinguishes between past and future, the only one that can explain irreversible processes, such as evolution and growth. The temptation is irresistible. But the true implications of the law of entropy (and even the very definition of entropy) are far from being well understood. Modern physics adheres to the Cosmological Principle that the average properties of the universe are the same everywhere and in every direction, that the laws of nature are invariant under translations and rotations, i.e. the universe is "isotropic". The US physicist David Layzer ("Cosmogonic Processes", 1968) turned it into the "Strong Cosmological Principle": there was nothing in the initial state that gives a position or a direction a preferred status. It follows from this principle that randomness is a property of the universe. "A complete description of the universe contains only statistical information", and the probabilities that figure in that "statistical information" simply reflect the absence of microscopic order (not our ignorance of the truth), and this absence of microscopic order is responsible for the decline of macroscopic order embedded in the second law of Thermodynamics. The "Strong Cosmological Principle" implies cosmological indeterminacy, i.e. that the more you know about the macrostate of the world the less you know about the microscopic states that cause it (a kind of indeterminacy related to Heisenberg's principle of indeterminacy). In other words, knowledge of the macrostate does not include knowledge of its corresponding microstates. Einstein's interpretation of the probabilistic nature of Quantum Mechanics was similar: Quantum Mechanics is a statistical theory useful to describe sets of particles, but not individual objects. Likewise, Layzer believes that we can only describe statistical properties. Layzer, however, parts from Einstein in explaining the origin of this limitation: Einstein thought that it was simply due to our ignorance of the fundamental laws of nature, whereas Layzer thinks that it follows from the equivalence of all positions and all directions anywhere in the universe. In theory, as Clausius and Boltzmann realized, the universe should be doomed to decline towards states of decreasing order because natural processes generate more and more entropy. One would conclude that at the beginning the universe was more orderly than it is now. Layzer, however, points out that this is not necessarily true in an expanding universe: order is created by the cosmic expansion. If entropy in the environment increases more than the entropy of the system, then the system becomes more ordered in that environment. Entropy and order can both increase at the same time without violating the second law of thermodynamics. Unlike Prigogine, Layzer does not need to assume that an energy flow from the environment of a system can cause a local decrease in entropy within the system. Entropy and order increase together because, technically speaking, the realization of structure lags behind the expansion of phase space. Layzer does not believe that the universe was born complex and hot. He believes that such a vision leads to blatant contradictions, whereas an initially structureless and cold state accounts for the features of the universe that we observe today, starting with gravitational clustering, as that kind of state inevitably leads to a hierarchy of self-gravitating clusters. The alternative to Boltzmann's model (that the universe began in a highly ordered state) is a model in which the initial state had no order at all and order (the hierarchy of self-gravitating clusters) was created as it cooled down and density fluctuations got amplified, each self-gravitating assembly becoming a component to generate with other peers the next self-gravitating assembly. Order was created because a gravitating gas with negative internal energy in an expanding medium is inherently unstable. Layzer believes that order must be given the same status as energy among the fundamental features of the world, and in that case living organisms have something that nonliving organisms don't have: a special kind of organization. Living matter is made of the same stuff as nonliving one, but they way it is organized is different. In his opinion this approach can help solve the mystery of why evolution tends to create more complexity. In theory there should be no average improvement or decline in complexity. In practice there has been a vast improvement from the first living cell to today's life. He quotes Peter Medawar: "The inexplicable tendency of organisms to adopt ever more complicated solutions to the problem of remaining alive" ("A Biological Retrospect", 1982). The fundamental property of living organisms is, to Layzer, "reproductive instability", a property that turns life into a kind of viral infection: "Just as a virus transforms its living host into a factory for producing more virus, so life transforms its inert host into a factory for producing more life". He traces this reproducing instability back to an inherent instability of genetic material, and this one back to a property of all molecules organized in a particular way. Evolution is due to the cooperation of two processes: variation and selection. Genetic variation allows new forms of life to emerge and natural selections determines which ones survive and reproduce. In 1949 the Russian zoologist Ivan Schmalhausen proposed that evolution is a process of hierarchical construction leading to a functional hierarchy in which each functional unit is created by aggregation of preexisting functional units. Genetic variation is the consequence of this general process of hierarchical construction, and evolution shaped this hierarchical process. Therefore, Layzer argues that genetic variation, that indirectly shapes evolution, is not a random process but was shaped by evolution itself. Because it is not random, but driven by a hierarchical process, it ends up fostering complexity, and the apparent paradox is solved. In detail, Layzer distinguishes alpha and beta genes. Alpha genes are the genes of classical genetics and the regulatory genes that transcribe these genes into RNA. Beta genes are not directly involved and serve maintenance chores. Layzer's theory is that beta genes drive evolution by promoting mutations that are likely to increase fitness and suppressing mutations that are likely to decrease fitness. He then argues that hierarchical construction is the natural consequence of this system. Biological order is not only created by evolution, it is also created by development. Biological order due to evolution is embodied in DNA. Biological order due to development is embodied in neural connections. Layzer adopts the stance of ecological realism, that perception is an active process during which we construct our cognitive life. That too is a hierarchical structure. Inside the brain Layzer finds again a hierarchy, this time a hierarchy of neural circuits modeled after Alexander Luria's three functional units (1942). His "Strong Cosmological Principle" has made randomness a property of the universe: the universe began from a state of pure randomness (zero order). He uses that randomness to prove that creative processes such as biological evolution (as well as cultural evolution) inevitably generate order in an unpredictable way. The future (both of life and of human behavior) is not predetermined. Back to the beginning of the chapter "The Physics Of Life" | Back to the index of all chapters