Is Darwinism a Theory in Crisis?
Jonathan Wells
Editor’s note: We are a delighted to present a new series by biologist Jonathan Wells asking, “Is Darwinism a Theory in Crisis?” This is the first post in the series, which is adapted from the recent book, The Comprehensive Guide to Science and Faith. Find the full series here.
What does it mean to say that a theory is “in crisis”? It’s not enough to point out that a theory is inconsistent with evidence. Critics have been pointing out for decades that Darwinism doesn’t fit the evidence from nature. Biologist Michael Denton published Evolution: A Theory is Crisis in 1986.1 Thirty years later, he drove the point home with Evolution: Still a Theory in Crisis.2
But Darwinism is still with us, for two reasons. First, Darwinism is not just a scientific hypothesis about specific phenomena in nature, like Newton’s theory that the gravitational force between two bodies is inversely proportional to the square of the distance between them (17th century), Lavoisier’s theory that things burn by combining with oxygen (18th century), or Maxwell’s theory that light is an electromagnetic wave (19th century). Darwin called On the Origin of Species “one long argument,” and a central part of it was a theological argument against the idea that species were specially created.3
Second, established scientific research programs such as Darwinism are never abandoned just because of some problems with the evidence. The idea that all species are descendants of one or a few common ancestors that have been modified by mutation and natural selection will maintain its dominance until large numbers of scientists embrace a competing idea. Currently, the major competing idea is intelligent design (ID), which maintains (contra Darwin) that some features of living things are better explained by an intelligent cause than by unguided natural processes. The shift, if and when it happens, will be a major scientific revolution. One way to approach this phenomenon is through philosopher of science Thomas Kuhn’s 1962 book The Structure of Scientific Revolutions.4
I will begin by summarizing some of Kuhn’s key insights. I will then apply those insights to the present conflict between Darwinism and intelligent design. As I do so, I point out some problematic aspects of Kuhn’s work, but I conclude that recent events fully justify calling Darwinism a theory in crisis.
Kuhn’s Structure of Scientific Revolutions
According to Kuhn, “normal science” is “research firmly based upon one or more past scientific achievements, achievements that some particular scientific community acknowledges for a time as supplying the foundation for its further practice.” Those achievements were “sufficiently unprecedented to attract an enduring group of adherents away from competing modes of scientific activity.” They were also “sufficiently open-ended to leave all sorts of problems” to be solved. Kuhn called achievements that share these two characteristics “paradigms.”5
Once a paradigm becomes dominant, the normal practice of science is simply to solve problems within that paradigm. In the process, an “institutional constellation” forms that includes “the formation of specialized journals, the foundation of specialist societies, and the claim for a special place in the curriculum.”6 The last is very important, because one “characteristic of the professional scientific community [is] the nature of its educational initiation.” In “the contemporary natural sciences…the student relies mainly on textbooks” until the third or fourth year of graduate work, at which point the student begins to do independent research. “It is a narrow and rigid education, probably more so than any other except perhaps in orthodox theology.”7
A First Line of Defense
Kuhn wrote,
No part of the aim of normal science is to call forth new sorts of phenomena; indeed, those that will not fit the box are often not seen at all. Nor do scientists normally aim to invent new theories, and they are often intolerant of those invented by others.8
Yet “no paradigm that provides a basis for scientific research ever completely resolves all its problems.” When anomalous evidence emerges, however, scientists’ first line of defense is usually to “devise numerous articulations and ad hoc modifications of their theory in order to eliminate any apparent conflict.” They never simply renounce the paradigm unless another is available to take its place. Thus “the decision to reject one paradigm is always simultaneously the decision to accept another,” and “the judgment leading to that decision involves the comparison of both paradigms with nature and with each other.”9
How Paradigms Originate
The most effective claim that proponents of a new paradigm can make is that “they can solve the problems that have led the old one to a crisis.”10 Even then, Kuhn wrote,
The defenders of traditional theory and procedure can almost always point to problems that its new rival has not solved but that for their view are no problems at all…Instead, the issue is which paradigm should in the future guide research on problems many of which neither competitor can yet claim to resolve completely. A decision between alternate ways of practicing science is called for, and in the circumstances that decision must be based less on past achievement than on future promise.11
How does a new paradigm originate? Kuhn wrote,
Any new interpretation of nature, whether a discovery or a theory, emerges first in the mind of one or a few individuals. It is they who first learn to see science and the world differently, and their ability to make the transition is facilitated by two circumstances that are not common to most other members of their profession.12
First, Kuhn wrote, “their attention has been concentrated upon the crisis-provoking problems.” Second, these individuals are usually “so young or so new to the crisis-ridden field that practice has committed them less deeply than most of their contemporaries to the world view and rules determined by the old paradigm.”13
According to Kuhn
Paradigms differ in more than substance, for they are directed not only to nature but also back upon the science that produced them. They are the source of the methods, problem-field, and standards of solution accepted by any mature scientific community at any given time. As a result, the reception of a new paradigm often necessitates a redefinition of the corresponding science.14
Notes
1)Michael Denton, Evolution: A Theory in Crisis (Bethesda, MD: Adler & Adler, 1986).
2)Michael Denton, Evolution: Still a Theory in Crisis (Seattle, WA: Discovery Institute Press, 2016).
3)Stephen Dilley, “Charles Darwin’s use of theology in the Origin of Species,” British Journal for the History of Science 45 (2012), 29-56.
4)Thomas S. Kuhn, The Structure of Scientific Revolutions (Chicago, IL: University of Chicago Press, 1962).
5)Thomas S. Kuhn, The Structure of Scientific Revolutions, 2d ed. (Chicago, IL: University of Chicago Press, 1970), 10.
6)Kuhn, The Structure of Scientific Revolutions, 2d ed., 19, 93.
7)Kuhn, The Structure of Scientific Revolutions, 2d ed., 164-166.
8)Kuhn, The Structure of Scientific Revolutions, 2d ed., 24.
9)Kuhn, The Structure of Scientific Revolutions, 2d ed., 77-79.
10)Kuhn, The Structure of Scientific Revolutions, 2d ed., 153.
11)Kuhn, The Structure of Scientific Revolutions, 2d ed., 157-158.
12)Kuhn, The Structure of Scientific Revolutions, 2d ed., 144.
13)Kuhn, The Structure of Scientific Revolutions, 2d ed., 144.
14)Kuhn, The Structure of Scientific Revolutions, 2d ed., 103.
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