Autor: Mehrere Autoren: Theological Studies; 01-SEP-06

Buch: Theological Studies; 01-SEP-06

Titel: Byrne, Patrick H., Evolution, randomness, and divine purpose: a reply to Cardinal Schonborn

Stichwort: Evolution als zufällig; Totalität der Evolution: relativer Zufall (in Bezug auf klassische Naturgesetze), aber nicht absoluter; Beispiel: Wundertüte (grab gab)

Kurzinhalt: All that can be said from the viewpoint of science is that the course of evolution can be and probably is random relative to the combined resources of the laws of the natural sciences.

Textausschnitt: EVOLUTION AS RANDOM

4a The kind of randomness that is relevant to neo-Darwinian theories of evolution has to do with the emergence of biologically advantageous characteristics and their immediate environment. A central tenet of neo-Darwinism is that the biological opportunities of an environment do not directly cause inheritance of advantageous characteristics. That is, the origination of inheritable genetic variations is random relative to their adaptive advantage in the immediate environment.1 If a relatively random series of mutations turns out to have adaptive advantage in the environment, then it will shift survival rates of its possessors and their progeny. But this series of mutations is a kind of happy accident; it does not arise because of any direct, intelligible pattern that connects advantage with the immediate environment. (Fs) (notabene)

4b Specifically, Darwinian explanations have long denied that an organism can pass along to its progeny a characteristic acquired by its own activity in response to the demands of its environment. More generally, neo-Darwinian explanations deny any "emanation" from environmental niches that somehow directly affects the genetic material of an organism, which will thereby improve its offspring's adaptations to the niches. Numerous studies have been conducted to find such direct correlations with immediate environments, but without success. (Fs) (notabene)

4c Technically speaking, then, the randomness required by neo-Darwinian explanations is specific and relatively limited. But to claim that genetic variations are absolutely random relative to every possible intelligibility is neither needed by neo-Darwinian science nor could it be verified on purely empirical grounds. The more limited, relative randomness essential to neo-Darwinian science is not, as such, incompatible with God as transcendent and purposeful creator. (Fs)

4d Scientists commonly hold that there is an even more sweeping sense of randomness than that required by neo-Darwinism which plays a constitutive role in the natural world. Yet, even this more sweeping sense of randomness is not absolute randomness--that is, it is not a denial of every sort of intelligibility whatsoever. To bring this more sweeping randomness into focus, consider the entire set of all the events that led up to the totality of all of today's organisms. This totality includes: all the sequences of genetic mutations that ever occurred; all the events that led to each of these mutations--radiation events, chemical toxins, pH imbalances, chromosomal breakages and crossovers, and gene transpositions, etc., as well as all their occasioning events; all the anatomical and physiological variations that resulted from the genetic mutations in the organisms that actually reached maturity; all the premature deaths of other organisms containing these mutations; all the events that brought organisms together at particular places and times resulting in successful mating and reproduction; and all the events that prevented successful reproduction and propagation of the genetic innovations and phylogenic variations, including the elimination of genetic strains through extinctions. This entire set of events (with all its complex myriad of intelligible strands, sequences, and interconnections) is the whole course of the evolution of the universe and nature as it has actually occurred. It is a radically contingent course of evolution, since, after all, many other courses of evolution are also possible and equally compatible with basic neo-Darwinian principles.2 (Fs)

4e The events in this vast array of physical, chemical, and biological transitions are connected by a series of applications of the laws of physics, chemistry, and biology. But from the point of view of those sciences alone, the entire sequence is random. That is to say, while each and every transition is completely explainable in terms of some subset of the laws of physics, chemistry, and biology, they are so only in terms of the prior conditions brought together at particular times and places. The laws of the sciences determine what would happen if those conditions were given, but they do not determine that those conditions must be given. It is as if the actual course of evolution were arbitrarily picked out of a grab bag of "all the possible sequences of events compatible with the laws of physics, chemistry, and biology." Hence the entire set of events in the evolution of life is random relative to the laws of physics, chemistry, and biology. (Fs) (notabene)

4f This notion of randomness is indeed sweeping and may very well be true of the actual course of events in the natural universe. Although it is breathtakingly extensive, it is still not absolute randomness, as it only involves the denial that the actual course can be completely determined--conditions and all--by the laws of physics, chemistry, and biology alone. This conception of randomness does not imply the denial of every possible intelligible pattern, for such a denial is beyond the methods of the empirical sciences. All that can be said from the viewpoint of science is that the course of evolution can be and probably is random relative to the combined resources of the laws of the natural sciences. (Fs) (notabene)