The Revolution Called Evolution

In his persuasive book, The Structure of Scientific Revolutions, Thomas Kuhn argued that the concept of a dominant paradigm would explain many of the unusual aspects of the way in which scientific thinking develops. He drew attention to the fact that scientific knowledge does not go on increasing steadily as more research is done. Instead, there are long periods of relatively steady growth punctuated by periods of crisis when, for a number of reasons, a whole set of assumptions and ideas are considered to be inadequate.

For example, the existing theories may not be able to cope with a mass of new experimental findings. When such a crisis occurs many novel suggestions are put forward. Even basic assumptions are questioned. From out of the welter of new ideas, one approach emerges which becomes widely accepted, usually because “it seems” most reasonable, and because it has real value in “explaining” or “relating” the new discoveries.

This newly accepted way of looking at things provides a basis for a re-orientation of the entire field. The revolution in physics which occurred as a result of Newton’s work is a good example. Another one is Dalton’s atomic theory, which in the early nineteenth century provided the basis for a century of research in chemistry. In each case the new theory provided not only an answer to a specific set of problems, but also a model which most scientists working in the field came to accept as “the” basis for progress. It provided a model for further theory construction and it came to be a source of generally accepted assumptions on which explorations were built. This is the new paradigm.

Once a paradigm becomes established it provides the basis for another long period of steady growth, or what Kuhn called “normal” science, as opposed to the “revolutionary” science of the crisis period. During the period of normal science new discoveries are made and new theories are constructed, but all within the guidelines of the existing dominant paradigm. This continues until the paradigm is again felt to be unworkable for reasons both within science and because of “outside” social factors. The breakdown of the paradigm ushers in another crisis period of revolutionary science, out of which a new paradigm will emerge.

The Copernican paradigm

A good example of a change in the accepted paradigm is to be found in the Copernican Revolution in astronomy. Copernicus (1473-1543), the Polish astronomer, did not discover any new facts about the heavens. Indeed it is likely that he only made a couple of dozen observations during his lifetime. Nor did he collect new data from anyone else. Nevertheless he is well known today as one of the father figures of astronomy. What did he do? To understand the significance of Copernicus and to see what it all has to do with paradigms we must first consider what were the basic theories of astronomy at this time.

The fundamental difference between astronomy before Copernicus and modern astronomy was that the earlier astronomy assumed, as a matter of course, that the Earth was the centre of the universe and that all of the heavenly bodies rotated around it. Now it is easy for us to laugh at such a “silly” idea, but before we laugh too loudly we ought to consider how the problem would look to a perfectly reasonable and rational person in 1500 A.D. The facts are these:

1. Various colored lights appear in the sky, one or two by day, many at night.
2. They all move from East to West (except the odd one which “falls” out of position).
3. Most of the stars remain in a fixed pattern.
4. Five stars plus the sun and the moon wander about on the fixed pattern rather like an ant on the carpet pattern, but they still move from East to West.
5. The Earth doesn’t seem to move.

The ancients and medievals could explain everything they could observe by assuming that the Earth was fixed in one place and that the others rotated around it—possibly fixed to a series of concentric transparent (“crystalline”) spheres. This belief was reinforced by their idea that the Earth was the most important part of the visible universe, for on it was played out the great human drama of creation, fall into sin and redemption. Furthermore, there were a number of good arguments against the notion that the Earth moved. For instance, if the Earth moved the “fixed stars” wouldn’t appear to form constant patterns in the sky. The shape of Scorpio would appear to change as the Earth moved along, just as the view from a train window changes as we look at things from different directions.

Copernicus proposed that the Earth rotated around the sun and proceeded to put forward his theory in defiance of the conventional wisdom of his day. Subsequent findings tended to support his work and today we find it hard to imagine how intelligent people could ever have seen things in any other than the Copernican way. What has happened is that we now approach the whole problem with a different set of expectations and a different model. We look at the stars and think of ourselves as standing on a small speck of rotating matter. We don’t think of the stars racing across the sky, under the Earth and back ready the next evening. In other words we have a different paradigm; a different set of assumptions and the result is that we literally see things differently and therefore think about them differently. We have a different set of expectations and we are therefore attracted to different sorts of theories.

Darwin’s paradigm

Darwin’s Origin of Species provided a useful working hypothesis for biological scientists. However, it was not just one more theory in a period of steady scientific advance. It was written at a time of crisis for biology and geology. In the hundred years before 1859 the Biblical account of creation came under more and more attack. The Biblical framework or paradigm was becoming less acceptable. The reasons for rejection of a paradigm are very complex. Much more is usually involved than the discovery of some new factual evidence. In the case of the Biblical account of creation, the attack came from many directions. There was no reason within geology why the new discoveries of fossils and buried strata couldn’t have been accommodated within the creationist account. However, other forces were at work, and they were used to discredit the Biblical account for reasons other than scientific. Philosophical movements which denied the logical possibility of Divine intervention in the world. Literary-critical studies of the Old Testament etc. had as much, or even more effect than any scientific evidence. As a result of the application of Hegel’s philosophy to historical and sociological studies, evolutionary theory was inevitable.

Many people rejected the Biblical account of creation and a period of confusion or scientific revolution was experienced.

The end result was that many people rejected the Biblical account of creation and a period of confusion or scientific revolution was experienced. Out of the chaos of new ideas Darwin’s theory emerged as the one which came to be widely accepted. It became the new paradigm or framework for exploration of “origins.”

One of the characteristics of paradigms is that they are more than just dominant models for scientific theory construction. Darwin’s theory of evolution by natural selection was no exception. Not only has it become accepted as a virtually irrefutable theory, it has also become the model for thinking about a whole range of things not closely related to biology or geology. It has become the standard model for human affairs.

The following brief notes indicate some of the areas where evolutionary models have had an important influence.

The Darwinian paradigm—its influence

1. The notion of development from primitive to complex influenced many attempts to “re-date” the Old Testament, e.g. The Graf-Wellhausen theory depends on assumptions about “religious” ideas developing as a society develops.
2. In the History of Ideas a Darwinian model has reinforced the notion that good ideas are those which have survival value. From James and Dewey to Piaget and his “genetic epistemology” this has emphasized a relativism in all knowledge. This gives added support to the Hegelian idea that all “truths” are partial and limited.
3. As a result of 2, many attempts have been made to “translate” Biblical statements into statements in accordance with different, non-scientific worldviews. Hence Bultmann and “demythologizing,” etc.
4. Darwin’s model indicates a different view of man and his place in nature. Continuity between man and other animals is emphasized. This has influenced:
   1. Animal psychology as a way of approaching human psychology
   2. Continuity in method between animal and human psychology—hence rise of varieties of behaviorism.
   3. Ethics and conservation. “Whales have rights.”
   4. Heterodox theology such as de Chardin.
5. Concept of survival value as the goal of development has influenced various social and ethical theories.
   1. Haeckel (and probably Hitler), survival of the fittest! Also late nineteenth century racism.
   2. Social Darwinism (in America particularly) society as an organism - the emphasis on the collective. Adaptation as a personal and social good.