“Nothing in biology makes sense except in the light of evolution.”
– Theodosius Dobzhansky
Below you will find some excerpts from the writings of the late Ernst Mayr (1904 – 2005), one of the leading figures behind placing the thought and research of the field of evolutionary biology on its current path. (See, e.g., the Ernst Mayr Library at Harvard.)
In the first excerpts, Mayr provides a definition of what “Darwinism” means (One Long Argument: Charles Darwin and the Genesis of Modern Evolutionary Thought, Harvard University Press, 1991, pp. 90-107); in the second, taken from his essay “Teleology,” Mayr argues why teleological thinking has no place within evolution (What Makes Biology Unique? Cambridge University Press, 2004, pp. 39-66).
For anyone who has fallen prey to the “intelligent design” con, even at the intellectual level (i.e., rejecting right-wing politics, while remaining open to the notion of design and, of course, designers), I strongly recommend the second of these essays in particular. (For a contemporary example of the malevolent designs of “intelligent design,” see “Sternberg, Smithsonian, Meyer, And The Paper That Started It All,” Discovery Institute News, August 22, 2005. And for an analysis of the con, see “To the Greater Glory of the G.O.P.,” ZNet, August 23, 2005.)
As Mayr states his case at various points, the “clarification of the concept of teleology has greatly contributed to the conclusion that biology is a genuine science without any occult properties” (p. 49)—where by clarification, he means, ultimately, its elimination.
“Adaptedness…is an a posteriori result rather than an a priori goal seeking,” Mayr writes elsewhere. “For this reason, the word teleological is misleading when applied to adapted features” (p. 58). “There is adaptedness (Kant’s Zweckmässigkeit) in living nature but Darwin showed that its origin can be explained materialistically….None of the…teleological processes works backward from an unknown future goal; there is no backward causation” (p. 61).
And so on. For this line of empirically-rooted, anti-dogmatic, genuinely liberated thinking. (Or what Mayr in one passage excerpted below refers to as the “beliefs of every enlightened modern person.”)
“Our ignorance of the laws of variation is profound,” Darwin himself wrote in On the Origin of Species (1859). “Not in one case out of a hundred can we pretend to assign any reason why this or that part differs, more or less, from the same part in the parents.”
Still. Darwin had just concluded (Ch. V, “Laws of Variation,” p. 167):
For myself, I venture confidently to look back thousands on thousands of generations, and I see an animal striped like a zebra, but perhaps otherwise very differently constructed, the common parent of our domestic horse, whether or not it be descended from one or more wild stocks, of the ass, the hemionus, quagga, and zebra.
He who believes that each equine species was independently created, will, I presume, assert that each species has been created with a tendency to vary, both under nature and under domestication, in this particular manner, so as often to become striped like other species of the genus; and that each has been created with a strong tendency, when crossed with species inhabiting distant quarters of the world, to produce hybrids resembling in their stripes, not their own parents, but other species of the genus. To admit this view is, as it seems to me, to reject a real for an unreal, or at least for an unknown, cause. It makes the works of God a mere mockery and deception; I would almost as soon believe with the old and ignorant cosmogonists, that fossil shells had never lived, but had been created in stone so as to mock the shells now living on the sea-shore.
Apologies for the truncated nature of the excerpts from Mayr that follow. But I do not feel like transcribing whole chapters verbatim out of published books. So the excerpts will have to suffice.
Anyway. Here goes nothing.
The Writings of Charles Darwin on the Web (Homepage), John van Wyhe, Editor
The Structure of Evolutionary Theory, Stephen Jay Gould (Harvard Univeristy Press, 2002)
One Long Argument: Charles Darwin and the Genesis of Modern Evolutionary Thought, Ernst Mayr (Harvard University Press, 1991)
What Evolution Is, Ernst Mayr (Basic Books, 2001)
What Makes Biology Unique? Ernst Mayr (Cambridge University Press, 2004)
(A) “What Is Darwinism?” (From: One Long Argument: Charles Darwin and the Genesis of Modern Evolutionary Thought, Harvard University Press, 1991, pp. 90-107)
Immediately after 1859 the word Darwinism simply meant a rejection of special creation. If someone rejected special creation and adopted instead the inconstancy of species, common descent, and the incorporation of man into the general evolutionary stream, he was a Darwinian. Neither natural selection nor any special theory of speciation, nor even one’s belief in gradual versus saltational evolution, had any relevance to whether at that time one was considered a Darwinian or not….When someone in the 1860s or 1870s attacked Darwinism, he did so primarily in defense of creationism or natural theology against these four Darwinian concepts.
There is…one belief that all true original Darwinians held in common, and that was their rejection of creationism, their rejection of special creation….Nothing was more essential for them than to decide whether evolution is a natural phenomenon or something controlled by God. The conviction that the diversity of the natural world was the result of natural processes and not the work of God was the idea that brought all the so-called Darwinians together in spite of their disagreements on other of Darwin’s theories, and in spite of the retention by some of them [e.g., Asa Gray, Alfred Russel Wallace] of other theological arguments. This situation was quite well understood in the post-Origin period and that is why at that time, for Darwin’s opponents, Darwinism simply meant denying special creation and replacing it with the theory of evolution and in particular the theory of common descent.
If someone believed that the origin of the diversity of life was due to natural causes, then he was a Darwinian. But if he believed that the living world was the product of creation, then he was an anti-Darwinian.
The rejection of special creation, the inclusion of man into the realm of the living world (the elimination of the special position of man versus the animals), and various other beliefs of every enlightened modern person are ultimately all based on the consequences of the theories contained in the Origin of Species.
Darwin’s proposed mechanism, natural selection, was almost universally rejected, but since the fact of evolution and the theory of common descent were so completely convincing after Darwin had pointed them out, other evolutionists simply adopted—instead of natural selection—various other kinds of mechanisms, whether teleological, Lamarckism, or saltational. Indeed, for Darwin himself, as much as be believed in natural selection all his life, it was obviously not his mechanism that was of first important for him but the evidence for evolution and common descent.
The version of Darwinism that developed during the evolutionary synthesis [of the 1930s and 1940s] was characterized by its balanced emphasis both on natural selection and on stochastic processes; by its belief that neither evolution as a whole, nor natural selection in particular cases, is deterministic but rather that both are probabilistic processes; by its emphasis that the origin of diversity is as important a component of evolution as is adaptation; an by its realization that selection for reproductive success is as important a process in evolution as selection for survival qualities.
After 1859, that is, during the first Darwinian revolution, Darwinism for almost everybody meant explaining the living world by natural processes….[D]uring and after the evolutionary synthesis [of the 1930s and 1940s] the term “Darwinism” unanimously meant adaptive evolutionary change under the influence of natural selection, and variational instead of transformational evolution.
(B) “Teleology” (From: What Makes Biology Unique? Cambridge University Press, 2004, pp. 39-66)
[S]ince 1859 no explanation in the biological sciences has been complete until a third kind of question was asked and answered: “why?” It is the evolutionary causation and its explanation that is asked for in this question. Anyone who eliminated evolutionary “why” questions closes the door on a large area of biological research. Therefore it is important for the evolutionary biologist to demonstrate that “why?” questions do not introduce a new metaphysical element into the analysis and that there is no conflict between causal and teleological analysis.
Day is the telos of the night. All processes caused by natural laws sooner or later have an endpoint, but it is misleading to use for this termination the same word telos that is ordinarily used for the goal of a goal-directed process. The endpoint of a non-teleological process is, so to speak, an a posteriori phenomenon.
Descriptions of the physiological functioning of an organ or other biological feature are not teleological. Indeed, in favorable cases, they can be largely translated into physiochemical explanations; they are due to proximate causations. What is involved in an analysis of teleological aspects is the biological role of a structure or activity. Such roles are due to evolutionary causations.
Features that contribute to the adaptedness of an organism are in the philosophical literature usually referred to as teleological or functional systems….It was adopted by the older philosophical literature under the assumption that these features had originated through some teleological force of nature. This assumption was largely a heritage of natural theology, with its belief that the usefulness of each feature had been given by God….Darwin has taught that seemingly teleological evolutionary changes and the production of adapted features are simply the result of variational evolution, consisting of the production of large amounts of variation in every generation, and the probabilistic survival of those individuals remaining after the elimination of the least-fit phenotypes. Adaptedness thus is an a posteriori result rather than an a priori goal seeking. For this reason, the word teleological is misleading when applied to adapted features.
One of the characteristics of adapted features is that they can perform teleonomic activities. They are, so to speak, executive organs for teleonomic programs.
Before the nineteenth century, the belief was almost universal that change in the world was due to an inner force or tendency toward progress and to ever-greater perfection….The most determined opponents of natural selection were teleologists.
There is no cosmic teleology; there is no trend in the world toward progress or perfection. Whatever changes and trends in the cosmos are observed in the course of the world’s history, they are the result of the action of natural laws and natural selection.
The process of natural selection, acting in every population, generation for generation, is indeed a mechanism that favors the rise of ever better-adapted species; it favors the invasion of new niches and adaptive zones; and as the end-result of competition among species it would favor development of what are best described as advanced types. Descriptively there is no question about what has happened during the diverse steps from the most primitive bacteria to humans. Whether one is justified in referring to this as progress is still controversial. This much is clear, however: natural selection provides a satisfactory explanation for the course of organic evolution and makes an invoking of supernatural teleological forces unnecessary. And those who accept the occurrence of advance or progress in evolution do not ascribe it as due to teleological forces or tendencies but rather as the product of natural selection.
The removal of [teleological thinking] leaves no residue….The recognition that…seemingly teleological processes…are strictly material phenomena has deprived teleology of its former mystery and supernatural overtones. There is adaptedness (Kant’s Zweckmässigkeit) in living nature but Darwin showed that its origin can be explained materialistically. Even though there are indeed many organic processes and activities that are clearly goal-directed, there is no need to involve supernatural forces, because the goal is already coded in the program that directs these activities. Such teleonomic processes, in principle, can be reduced to chemicophysical causes. Finally, there are all the end-achieving processes in inorganic nature that are simply due to the operation of natural laws such as gravity and the laws of thermodynamics. None of the…teleological processes works backward from an unknown future goal; there is no backward causation.
After Darwin established the principle of natural selection, this process was widely interpreted to be teleological, both by supporters and by opponents. Evolution itself was frequently considered a teleological process because it would lead to “improvement” or “progress”….However, it is no longer a reasonable view when one fully appreciates the variational nature of Darwinian evolution, which has no ultimate goal and which, so to speak, starts anew in every generation….[Y]et considering how often natural selection leads into fatal dead ends and considering how often during evolution its premium changes, resulting in an irregular zigzag movement of the evolutionary change, it would seem singularly inappropriate to use the designation teleological for any form of directional evolution. To be sure, natural selection is an optimization process, but it has no definite goal, and, considering the number of constraints and the frequency of chance events, it would be most misleading to call it teleological. Nor is any improvement in adaptation a teleological process, because whether a given evolutionary change qualifies as a contribution to adaptedness is strictly a post hoc decision.
Natural selection deals with properties of individuals of a given generation; it simply does not have any long-range goal, even though this may seem so when one looks backward over a long series of generations.