from natural law.
Evolutionary Ordering and the Limited Scope of Darwinian Theory
Although evolutionary theory as first articulated in the works of the Naturphilosophs, and in the work of English scholars such as Chambers and Spencer (who first popularized the term "evolution") were general theories of change where physics, biology, and psychology were, in principle, commensurable parts of a universal law-based process, with the ascendancy of Darwinism, the idea of evolution became progressively reduced in meaning. Today evolution and Darwinism are typically taken to be synonymous, and the "almost universally adopted definition of evolution is a change in gene frequencies" (Mayr, 1980, p. 12) following from natural selection. Whatever the internal differences there are between various sects of contemporary Darwinism, the core concept is that evolution is that which follows from natural selection (Depew & Weber, 1995). Natural selection is taken to be the fundamental explanation or true cause (vera causa) of evolution. In the final quarter of this century it has become widely recognized that an evolutionary theory so defined must itself, by definition, be fundamentally incomplete. It is not that any serious doubt has been cast on the fact of natural selection. It is that natural selection by itself is not sufficient for a comprehensive or robust evolutionary theory. In particular, natural selection cannot explain the active, end-directed, striving of living things (the "fecundity principle"), nor can it address the fact of planetary evolution, a special case of the problem of the population of one.
The Fecundity Principle or Biological Extremum
Evolution, on the Darwinian view, is taken to be the consequence of (is "explained by") natural selection, but natural selection is itself the consequence of the active, end-directed striving, or intentional dynamics, of living things. Natural selection, said Darwin (1959/1937, p. 152), follows from a population of replicating or reproducing entities with variation "striving to seize on every unoccupied or less well occupied space
|in the economy of nature".
Because "every organic being," he said (Darwin, 1959/1937,
p. 266), is "striving its utmost to increase, there is therefore
the strongest possible power tending to make each site support
as much life as possible." As Schweber's (1985, p. 38) has
written, paraphrasing Darwin, this says that nature acts to "maximizes
the amount of life per unit area" given the constraints.
This makes up the content of the "fecundity principle"
or "biological extremum" (a principle stated in terms
of a maximum or minimum) from which natural selection follows,
and on which, it thus depends.
xxThe problem is that if natural selection follows from, or depends on, the active striving of living things expressed by the fecundity principle, then natural selection cannot explain this active striving. Natural selection cannot explain or account for the sine qua non of the living. It must, in effect, by smuggled in ad hoc.
xxDarwin, who did not intend to address these issues with his theory took the active properties of the living to have been "breathed into" dead matter by the Creator. The contemporary view has been that the active properties of the living came into the dead world of physics by an astronomically improbable "accident" that would only have to happen once (e.g., Dawkins, 1989). Given enough time, the argument goes, even an astronomically or infinitely improbable event can occur. Such an explanation which is really no better than Darwin's is unsatisfying for a number of reasons. For one thing such infinitely improbable "accidents" would have had to have happened not once but repeatedly to produce the evolutionary record we see. For another, the evolutionary record as it is now known shows that life arose on Earth and persisted, not after some long period of lifeless time, but as soon as the Earth was cool enough to keep the oceans from evaporating - as soon as it had the chance. This is the picture we now know of evolutionary ordering in general. Order typically arises as soon as it gets the chance, as soon as some constraint is removed or some minimal threshold reached. The urgency towards existence expressed in the fecundity principle is seen in the evolutionary record writ large, opposite on both counts with respect to the second law of thermodynamics as a law of disorder.
THERMODYNAMICS, EVOLUTION, AND BEHAVIOR - 218