Phil. 125








Practicing scientists get ahead in their field of science by intense concentration and specialization. To be recognized as successful, they must make original contributions in their specialty and not "waste" time on other pursuits. They aren't rewarded very much for writing introductory textbooks, for interpreting their field for fellow scientists, nor for popularizing their field to the general public. They are not rewarded for their breadth, for knowing even about other areas of their own science, nor for investigating any other science. Therefore, scientists aren't encouraged to develop a coherent picture of what the sciences tell us about the universe. Nor are they encouraged to develop an understanding of how the various sciences themselves work. This mastery of the breadth of the sciences, of the extent to which there is a coherent scientific world view, and of the methods by which the various sciences work must be done by philosophers of science, not by scientists.

A philosopher of science looks at science philosophically and investigates the philosophical questions that arise in the sciences. We will be doing this in our course. To begin, let's consider the philosophical question, "What is science?" There is a distinction between applied science and pure science although not a sharp one. Applied sciences are engineering, automotive repair, cosmetic science, and the activities of doctors who treat illness. They aren't pure science. Why aren't engineers doing pure science?  It's because engineers, like inventors, primarily want to improve existing things that have been made by humans, such as plows and X-ray machines, or to improve human beings' abilities to do new things, such as to improve our ability to move fast and to communicate easily with people who are far away. Pure scientists often do make use of advances in engineering, but they generally have different concerns. They are primarilyconcerned with classifying, explaining, predicting, and theoretical understanding. Engineers aren't. Engineering is focused on control, on getting the things to function as we want them to in a particular situation. So are doctors.




The new technology is very helpful to the rest of us, but its creation isn't science. Nevertheless, there's a deep connection between science and technology. Without a scientific understanding of electromagnetic waves, the TV and the computer would never have been invented by engineers. On the other hand, scientists need engineers and their new technology. For example, without the invention of the telescope, no scientist would have created the Big Bang theory of the origin of the universe.

We've seen how pure science can be distinguished from engineering, but how is pure science to be distinguished from art? Is science an art? No, but most people do not appreciate how much science is like art. Scientific theories do not automatically result from tedious data collection. To produce a theory that has great explanatory power is engage in a very creative act. That's one way science is like art; scientists and artists engage in very creative acts. One way science not like art is that scientific theory must be true to the way the world is. So, science has similarities with art, but also deep differences.




"Science" is the Latin term for knowledge. By "science" we will mean empirical science, the kind of science that is based on observation or experimentation. That rules out the "science of mathematics."

To begin, let's precisely define three important empirical sciences: biology, chemistry, and physics. Definitions: If it wiggles, then it's biology; if it stinks, then it's chemistry; and if it doesn't work, then it's physics. Hmmm. Not very good definitions. There are better definitions but no really good ones because ultimately chemistry is whatever the chemists do, and so forth. But no one really needs a precise definition.

Although the scientist's vocabulary is often so technical that the rest of us cannot read a scientific research paper, science is not as distant from common sense as many people imagine. Scientists, like the rest of us, look around the world, try to explain what they observe, and are careful to back up what they say. Science is a slowed-down and more open and accountable image of what we normally do in coming to know about the world around us. Nevertheless, science isn't just common sense. Science often explains the familiar in terms of the unfamiliar, and science often overthrows traditional common sense in favor of new beliefs that can better stand up to testing. It once was common sense that the Earth is flat; but that belief is no longer common sense; it's a mistake. The new common sense is that the Earth is not flat.

Everybody agrees that science is important, but some people think it is much more important than others do. According to the distinguished historian of science Herbert Butterfield, the rise of European science in the 17th and 18th centuries

...outshines everything since the rise of Christianity and reduces the Renaissance and Reformation to the rank of mere episodes....It changed the character of men's habitual mental operations even in the conduct of the nonmaterial sciences, while transforming the whole diagram of the physical universe and the very texture of human life itself.

The scientific revolution Butterfield is talking about was noteworthy for promoting the notion that scientific knowledge should be produced by the process that we now call "the scientific method." This new method was very different from the medieval method of attempting to acquire knowledge from careful reading of ancient texts. Our philosophical study of science will investigate the nature of this new scientific method. The key idea of this method is to run experiments to check on hypotheses, Hypotheses are interesting claims about how things are. The ancient Greeks also conducted experiments occasionally, but William Gilbert in the 17th century was the first person to methodically tie his experimental observations to the theories he proposed and to intentionally provide the necessary detail used in his experiments so that others could reproduce his results and find out for themselves. In short, Gilbert was more scientific because of his use of the scientific method. His idea of how to gain knowledge caught on and transformed the world.




There are other kinds of philosophical problems involving science that we will be studying. Consider the process of scientific change. Scientific textbooks are different this century than last century. Pointing to this as a lesson from the past, some philosophers conclude that this year's scientific results will be overturned by next year's results, and therefore today's Nobel prizes are being awarded for bogus contributions to knowledge, and billions of dollars are being spent on the detection of fictitious particles. Other philosophers have challenged this assessment of scientific change. Our job will be to understand the reasons for this disagreement.

Philosophers of science do not do science, nor do they tell scientists how to do it. Yet scientists continually make philosophical assumptions even if they don't usually realize they are doing so. Philosophers of science spend some of their time trying to make those assumptions explicit and then subjecting the assumptions to critical examination. For example, scientists claim to know the mass of an electron. The mass was determined from several measurements at several labs over a few years. On this basis they claim to know the mass of the electrons that were inside the Sun a thousand years ago. Yet these scientists have never visited the Sun a thousand years ago. Evidently certain interesting assumptions are involved here.

In addition to examining assumptions and wrestling with paradoxes, philosophers of science analyze concepts to see if they make sense or if they lead people to confusions. A confused person might ask, "Has science confirmed or instead refuted the hypothesis that the Earth is right-side-up?" Most of us will immediately realize that the question is weird and be able to diagnose why it is weird. In real life, philosophers of science don't waste their time on unsophisticated mistakes. They are interested in more sophisticated mistakes that are behind questions such as the following: "If time began with the Big Bang, then what happened before that?" and "What was the crucial experiment that should convince the rational person to accept Charles Darwin's theory of evolution and to reject the alternatives?" and "If an electron is a zero-dimensional object, then isn't it too small to be a physical object?" and "If a quantum field theory implies that something comes from nothing, doesn't that violate our metaphysical knowledge that this is impossible and therefore doesn't that prove the scientific theory to be incorrect?" We will investigate why these are bad questions.

The deeper, and ultimately more interesting, questions are these: Does scientific knowledge rest on firm foundations? What, precisely, is the scientific method, or is there such a thing? What is required of a scientific explanation in order that it be a good explanation? What are the limits on what science could ever know? Our class will explore the major answers to all of these deep questions.

Although philosophers have tried to answer these philosophical questions about science, the answers have not been generally accepted by other philosophers. In contrast, scientists have answered many of the great scientific questions, and their answers are generally agreed to by the other scientists. Therefore, one of the most important differences between philosophy and science is that philosophy is not a discipline defined by a group of previously solved questions and agreed-upon answers. Philosophy of science is better defined by its interests, methods and agreed-upon questions.



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updated: 7/14/09