This course discusses the question of whether scientific progress is the result of a gradual accumulation of research achievements or a revolutionary paradigm shift. Focusing on Thomas Kuhn’s theory of scientific revolutions, it explores the nature of scientific progress by explaining the relationship between steady-state and revolutionary scientific development, as well as its counterarguments and limitations.
Is scientific progress a continuous accumulation of research achievements? If you haven’t thought about this topic in depth, most people would say yes. And this was the prevailing opinion before Thomas Kuhn. However, Thomas Kuhn revolutionized our understanding of how science works when he published The Copernican Revolution and The Structure of Scientific Revolutions.
Of course, science still works by accumulating research results based on established theories and expanding our understanding of the world little by little. In fact, this is what most scientists do. Refining the standard theory in particle physics, trying to calculate the motion of the planets using Newtonian mechanics, or the work of astronomers before the Copernican revolution are all examples of this. This period of science is called normal science. Normal science is essentially puzzle-solving. Puzzlers and scientists are similar in that they both know that the answer exists, and they both know the rules used to solve it. The rules used to solve the puzzle are the paradigm.
Normal science is the process of solving detailed problems through stable, ongoing research. This allows us to make accurate predictions of natural phenomena, and makes many technological advances in our daily lives possible. For example, advances in weather prediction systems or communication technologies are based on the achievements of normal science. The accumulation of normal sciences paves the way for humanity to gain a deeper understanding of nature, and in this respect, normal sciences play a very important role.
However, according to Thomas Kuhn, the truly creative and great advances come not from normal science, but from scientific revolutions. A scientific revolution is a process in which a paradigm that is the framework of normal science is replaced by a new paradigm, such as the Copernican revolution or the replacement of Newtonian mechanics by Einstein’s theories.
In the normal course of science, there are often phenomena or findings that don’t fit well with existing theories. This is called an anomaly. However, the appearance of an anomaly does not mean that all scientists abandon their theories. Rather, they see anomalies as counterexamples to existing theories and abandon the existing paradigm. In many cases, these anomalies can be understood by applying existing theories. This is when we succeed in solving the mystery. In the case of epicycles, the retrograde motion of the planets is an anomaly. However, rather than questioning the belief that the Earth is at rest, the concept of a mains power source was introduced to explain the retrograde motion.
However, some serious anomalies cannot be interpreted within the framework of existing theories. This is where the crisis comes in. Copernicus believed that he could not continue to explain the retrograde motion of the planets by introducing large and small primary sources, and this can be considered a crisis of the heliocentric theory.
In times of crisis, some scientists step outside the framework of existing theories and introduce new theories. These new theories are still immature and not as accurate as the old ones, but they provide a new way of looking at phenomena. The birth of geodynamics is an example of this. However, the language of the two paradigms is different, so it is not possible to compare which is the superior paradigm. This is known as incommensurability, so the choice of which paradigm to adopt is entirely a matter of personal preference, and Thomas Kuhn likened the process of choosing a new paradigm to religious conversion.
Over time, as the new theoretical framework becomes more precise, and as the authority figures in the group of scientists who adhered to the old theory begin to recede, most scientists will agree to the new paradigm. This process of consensus among the scientific community is known as a scientific revolution.
However, there are objections to Thomas Kuhn’s argument. First of all, there is the question of whether all sciences really develop from a normal science to a new normal science through a scientific revolution, as Thomas Kuhn says. Examples of scientific revolutions according to Thomas Kuhn include the Copernican revolution, the acceptance of relativity, quantum theory, Lavoisier’s chemical revolution, and Darwin’s theory of evolution. However, most of these are in the realm of physics, and the references in the text are mainly to physics. Given that Thomas Kuhn began his studies as a physicist, it’s understandable that he’s talking primarily about physics, but it’s unclear whether his explanations apply to other fields of science. In his book This is Biology, biologist Ernst Meyer argued that there was never a period of steady state science in biology, noting that the concept of evolution had been around for more than a century before the publication of The Origin of Species, and that it was not accepted until 100 years after its publication. According to him, biology is fundamentally different from physics in subject matter, history, methodology, and philosophy.
It is also uncertain whether the Copernican Revolution, which is often cited as a prime example of a revolution, was really a revolution at all. It took over 100 years for the geodynamic theory to be proposed and fully accepted. Of course, a paradigm shift from celestial to geodynamic is a huge event. However, the fact that it took this long for the paradigm to shift suggests that it is somewhere in between a gradual accumulation and a revolution rather than a revolutionary change.
Thomas Kuhn also emphasized that because of the incommensurability of paradigms, the choice of paradigm by individual scientists is not based on rational criteria alone, which may be an undue criticism of science. Since science is an activity conducted by scientists and their societies, it is natural to expect temporary irrationality during paradigm shifts. What matters is the steady progression of rationality over a longer period of time, rather than the irrationality of those brief periods.
Thomas Kuhn’s The Structure of Scientific Revolutions has had a profound impact on the way people think about the term “paradigm,” not only in the history of science, but also in the humanities, philosophy, and everyday life. As Thomas Kuhn pointed out, the history of science is marked by revolutionary changes that cannot be explained by gradual accumulation alone, but it is unclear whether these revolutionary changes are simply a matter of a few episodes, or whether the nature of science is that it develops through revolutionary paradigm shifts. In addition, the irrationality of scientists and scientific societies is inevitable as long as we are human, and the important thing is that science continues to advance despite such irrationality.
