Thomas Kuhn's "The Structure of Scientific Revolutions"

Transcription

1 Thomas Kuhn's "The Structure of Scientific Revolutions" Big History Project, adapted by Newsela staff Thomas Kuhn ( ) was an American historian and philosopher of science. He began his career in theoretical physics before switching career paths. His book, The Structure of Scientific Revolutions, which was first published in 1962, is one of the most cited academic books of all time and made Kuhn perhaps the most influential philosopher of science in the twentieth century. People had previously thought of progress in normal science as a continuous increase in a set of accepted facts and theories. Kuhn disagreed. He argued that the history of science has come in sudden bursts. Sometimes discoveries build on each other, but sometimes there is revolutionary science that interrupts the steady march of progress. In revolutionary science, a new paradigm, or worldview, changes the rules and direction of scientific research. His analysis of science, which called into question its objectivity, caused a firestorm of controversy. It continues to inspire reaction and debate in scientific communities and beyond. The following excerpts have been adapted from his book to provide a simplified view of Kuhn's arguments. I. A role for science Normal science, what most scientists spend most of their time doing, assumes that the scientific community knows what the world is like. The scientific community must defend this assumption if it wants to be successful.

2 Normal science often holds back fundamental novelties because they go against the accepted way of thinking. Still, as long as scientists are willing to be proved wrong, these novelties will eventually come out. Sometimes a normal problem, one that should be solvable by known rules and procedures, cannot be solved by the experts. Other times, a piece of equipment made for doing normal research gives results that don t make sense to the experts. In these and other ways, normal science repeatedly goes off track. Scientists have to face anomalies, or unexpected results they cannot explain. This is when they may begin extraordinary investigations that lead science to a new way of thinking, a new basis for the practice of science. These times, when science must accept new realities, are known in this essay as scientific revolutions. They shatter tradition, whereas normal science is bound to tradition. The most obvious examples of scientific revolutions are those famous episodes in scientific development that are already called revolutions. These include the major turning points in science associated with Copernicus, Newton, Lavoisier, and Einstein. These episodes display what all scientific revolutions are all about. Each of them caused the community to reject one accepted scientific theory for another one that was incompatible with it. Each brought a new set of questions for scientists to answer. Each brought new problems and new ways to solve these problems. Finally, each transformed the scientific imagination transformed the world where scientific work was done. These changes, and the controversies that go with them, are what define scientific revolutions. II. The route to normal science

3 In this essay, "normal science" means research firmly based on past scientific achievements. These past achievements form the foundation for further study. Today these achievements are described by science textbooks. These textbooks provide the core of accepted theory. They give examples of successful uses of these achievements, and compare these uses with observations and experiments. Before such books became popular early in the nineteenth century, many of the famous classics of science served a similar function. Aristotle s Physica, Ptolemy s Almagest, Newton s Principia and Opticks, Franklin s Electricity, Lavoisier s Chemistry, and Lyell s Geology these and many other works defined the problems and methods of research for future scientists. They were able to do so because they shared essential characteristics: First, the discoveries they presented had never before been seen. This attracted people from all fields to study them more. Also, these discoveries were open-ended enough to leave more questions for future researchers to answer. I ll call achievements that share these two characteristics paradigms. These paradigms provide models that produce unified traditions of scientific research. These are traditions that historians call Copernican astronomy or Newtonian dynamics and so on. A beginning scientist must study all the paradigms in his or her field before starting research. Scientists in a field rarely disagree over fundamentals, since they all have accepted the same paradigm. They share the same rules and standards. That agreement it produces is necessary for normal science for the creation and continuation of a research tradition. History suggests that the road to a firm research agreement is extraordinarily difficult. History also suggests, however, some reasons for the difficulties encountered on that road.

4 Without a paradigm, or a possible paradigm, all the facts that may relate to a given science all seem worth considering equally. In a new field of science, fact-gathering is more random that in a well-developed one. Furthermore, without a reason for seeking out more hard-to-find information, early fact-gathering tends to find the data that is convenient to find. Because the facts could not have been casually discovered, technology has often played a vital role in the emergence of new sciences. We can t study and interpret the natural world without a system of theories and methods that permits selection, evaluation and criticism. If that system is not in place, we have just facts. No wonder then, that in the early stages of any science different scientists seeing roughly the same things describe and interpret them in different ways. What is surprising, and maybe even unique in science, is that such differences should ever disappear. To be accepted as a paradigm, a theory must seem better than its competitors. But a theory never does explain all the facts it may face, nor does it have to. When, in science, an individual or group produces a new system that attracts most of the next-generation scientists, the older systems gradually disappear. In part, they disappear because members accept the new paradigm. But there are always some scientists who cling to older views, but they are often ignored by the scientific community. The new paradigm gives a stricter definition of what is acceptable. Those who don t agree with it must work alone or attach themselves to some other group. A paradigm can transform people merely studying nature into a profession. When an individual scientist can take a paradigm for granted, she doesn t have to explain the basic system in her works. She can assume that other scientists know the basic paradigm.

5 It is textbooks, then, that still have to explain things step by step, from the beginning. Active reading: Underline or highlight each sentence that you see the terms Scientific Revolution, Revolutionary Science, and Paradigm throughout the article. Article Assessment Questions 1.) According to the article, which of the following MOST influences "normal science"? A.) fundamental novelties B.) scientific revolutions C.) past scientific achievements D.) hard-to-find information 2.) Which of the following accurately characterizes how paradigms affect science? A.) Paradigms provide a basic agreement among scientists for understanding the world. B.) Paradigms are unexpected results that scientists must do more research to fully explain. C.) Paradigms cause normal science to go off track because they challenge and change theories. D.) Paradigms are strictly defined and cannot be changed once they have been accepted by scientists. 3.) Read the following sentence from the introduction [paragraphs 1-4].

6 His analysis of science, which called into question its objectivity, caused a firestorm of controversy. It continues to inspire reaction and debate in scientific communities and beyond. How does using the word "firestorm" affect the tone of the sentence above? A.) It conveys an objective tone that reflects the neutral scientific language used in Kuhn's work. B.) It conveys a cheerful tone that reflects the excitement of Kuhn's success in proving his theory. C.) It conveys a disappointed tone that reflects the frustration of other scientists who disagree with Kuhn's work. D.) It conveys a spirited tone that reflects the intensity of the scientific disagreement resulting from Kuhn's work. 4.) Read the following paragraph from the section "I. A role for science." These times, when science must accept new realities, are known in this essay as scientific revolutions. They shatter tradition, whereas normal science is bound to tradition. Which word from the paragraph above helps the reader understand that a scientific revolution c ompletely changes the beliefs that came before it? A.) accept B.) shatter C.) bound D.) tradition