Scientific Revolutions: Part 1

Scientific Revolutions

Occasionally, the scientific community rejects an idea that was previously widely accepted and replaces it with a new idea, which becomes the current consensus. This rapid change in scientific opinion is known as a “scientific revolution.”

These revolutions do not come easily because science is widely regarded as the most reliable, or even the only, pathway to truth. When an idea is said to be “unscientific,” this is generally interpreted to mean it is unreliable at best, and dangerously wrong at worst. In contrast, to describe a statement as “scientific” usually means it is believed to be true.

The high epistemological value placed on science is understandable but unwise. It is understandable because science has made discoveries that have been used in technologies to make our lives more comfortable and enable us to pursue learning and pleasure to an extent far greater than in the past. We are all grateful for the benefits received from scientific discovery. However, it is unwise to uncritically accept the pronouncements of “scientists” as though they are empirically confirmed, for at least two reasons. First, it is unwise because the prestige of science is often exploited by materialists to promote personal agendas with destructive outcomes. Second, the history of science tells us that scientists are often wrong, as seen in the occasional scientific revolution. This essay will focus on the latter phenomenon – revolutions in science.

Although not adequately appreciated in the popular press, many of those who study the history of science have come to see it more as a human enterprise than an application of pure reason. A major factor in this view was publication of the book The Structure of Scientific Revolutions in 1962, and more widely in the 1970 revision of the book.[i] In this book, Thomas Kuhn proposed that science is normally carried on as individuals seek application of general principles to more and more situations. Anomalies occur occasionally, but are ignored until they accumulate and people notice that there is a problem with the reigning paradigm. Attention is then focused on the anomalies, the paradigm is challenged and may be overthrown and replaced by a new paradigm. When this happens, a scientific revolution has occurred. Acceptance of a new paradigm may involve conversion of scientists, but often has to wait until the old guard dies out and is replaced by younger scientists who grew up with the new idea. In other words, new ideas are often accepted due to an influx of new people rather than by changing people’s opinions.

The scientific revolution[ii].

The first scientific revolution was the development of scientific methodology, utilizing experiment, mathematical analysis, and testing. This revolution transformed the study of the natural world from an exercise in cataloguing to an attempt to describe nature in mechanical terms and to make predictions. Key developments in this revolution were the application of mathematics to objects in motion by Galileo and Newton in the seventeenth century, and Harvey’s discovery of capillaries in the human body. Methodological developments were accompanied by formation of scientific societies with official journals, thus establishing a scientific community for the first time. This, the first scientific revolution, laid the foundation for the methodology and philosophy of modern science, and may rightly be called The scientific revolution.

The practice of science has expanded greatly since the original scientific revolution, and the term “revolution” has been applied[iii] to certain structural changes in the way scientific findings are funded and communicated. However, I prefer to apply the term “revolution” in a Kuhnian sense, that is, to relatively abrupt and radical changes in the way nature is understood. These are conceptual revolutions rather than sociological revolutions.

Conceptual revolutions in “the” scientific revolution

Several different conceptual revolutions contributed to “the scientific revolution.” Chief among them were the contributions of Nicolaus Copernicus (1473-1543) and Galileo Galilei (1564-1642), René Descartes (1596-1650), William Harvey (1578-1657), and Isaac Newton (1643-1727). The first of these was the “Copernican Revolution,” which radically changed our view of the place of the earth. Previously, the earth had been regarded as the center of the solar system, in a scheme formalized by Claudius Ptolemy in the second century, A.D. Unfortunately, the Christian church incorporated Ptolemy’s scheme into church dogma, using Biblical texts to attempt to support it. Copernicus proposed a different scheme in which the sun is the center of our solar system. The new view was vigorously opposed by the church, but eventually prevailed under the influence of Galileo and others. The Copernican revolution changed the public perception of humanity’s place in the universe from the center to the periphery, with corresponding changes in our relationship to God. It was truly a revolutionary idea.

René Descartes is credited with advances in mathematics and philosophy that produced a revolution in science. Descartes developed a system of mathematical graphing we still call “Cartesian coordinates,” which transformed mathematics, led to the development of general algebra, and enabled Newton to develop the calculus. Descartes also advocated a “mechanical philosophy,” which eschewed teleology in favor of a reductionist approach involving only matter and motion. Descartes’ influence was a major factor in the secularization of science, changing the scientific viewpoint from seeing the world as the handiwork of God to the point where LaPlace famously quipped to Napoleon “I have no need of that hypothesis,” meaning he intentionally left God out of his thinking in trying to explain the formation of the solar system.

William Harvey showed that the blood circulated in a single system linking the heart with the rest of the body, rather than being supernaturally moved by God. He accomplished this by meticulous dissection and study of the blood vessels and heart, and by direct measurement of the capacity of the heart, not only of humans, but also of sheep and dogs. Harvey’s application of experiment and observation, and especially his emphasis on quantitative measurements, transformed biology from a purely descriptive endeavor largely based on ancient authorities to an experimental science based on careful observation and measurement. The discovery that blood is pumped through the body by a mechanical heart removed the need for supernatural cause of blood flow, and helped bring biology into the realm of quantitative science.

Isaac Newton’s work was the capstone on the scientific revolution. Newton’s major contribution was the mathematization of physics. He developed the calculus and applied it to the study of motion. He developed generalized laws of motion, including curved motion, wave motion, and pendulums. His most dramatic contribution was the discovery and quantification of the force of gravity. He applied this to develop a model of the universe in which the planets and other heavenly bodies were guided in their orbits by gravitational forces. He also explained the tides as the result of gravitational forces of the sun and moon. In developing his model of a “clockwork universe,” Newton transformed the common perception of cause of the motion of the planets and stars. Previously, this was explained by the direct activity of God; now it was explained by the natural law of gravity.

The scientific revolution permanently changed the way we view our world. Before the revolution, nature was seen as the handiwork of God, and was studied mostly by clergymen. After the revolution, nature was seen as autonomous, and was studied mostly by professional scientists, many of whom were deists who believed God had no interaction with the universe. This view of nature as independent of any outside influence, dominant for the past two or three centuries, is itself under attack today as science continues to uncover the precise structure and complexity of the universe and the living organisms that inhabit it. Perhaps we are on the threshold of a new scientific revolution in which the reality of the supernatural is recognized. If so, it would be one more example in a list of revolutions in science.

L. James Gibson

Geoscience Research Institute

[i] Kuhn, T.S. 1970. The structure of scientific revolutions. 2nd edition, revised. Chicago: University of Chicago Press.

[ii] This and the next section are based largely on: Cohen, I.B. 1985. Revolution in science. Cambridge, MA: Harvard University Press.

[iii] E.g., Cohen, ibid.