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Philosophy of Science

Philosophy of Science

Professor Jeffrey L. Kasser Ph.D.
Colorado State University

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Philosophy of Science

Philosophy of Science

Professor Jeffrey L. Kasser Ph.D.
Colorado State University
Course No.  4100
Course No.  4100
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Course Overview

About This Course

36 lectures  |  30 minutes per lecture

Science can't be free of philosophy any more than baseball can be free of physics. With this bold intellectual swing for the fences, philosopher Jeffrey L. Kasser uses the tools of philosophy to launch an ambitious and exciting inquiry into what makes science science. In this brilliant course you will discuss

  • Why is science so successful?
  • Is there such a thing as the scientific method?
  • How do we distinguish science from pseudoscience?
  • Is science rational, cumulative, and progressive?

Focusing his investigation on the vigorous debate over the nature of science that unfolded during the past 100 years, Professor Kasser covers important philosophers such as Karl Popper, W. V. Quine, Thomas Kuhn, Paul Feyerabend, Imre Lakatos, Carl Hempel, Nelson Goodman, and Bas van Fraassen.

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Science can't be free of philosophy any more than baseball can be free of physics. With this bold intellectual swing for the fences, philosopher Jeffrey L. Kasser uses the tools of philosophy to launch an ambitious and exciting inquiry into what makes science science. In this brilliant course you will discuss

  • Why is science so successful?
  • Is there such a thing as the scientific method?
  • How do we distinguish science from pseudoscience?
  • Is science rational, cumulative, and progressive?

Focusing his investigation on the vigorous debate over the nature of science that unfolded during the past 100 years, Professor Kasser covers important philosophers such as Karl Popper, W. V. Quine, Thomas Kuhn, Paul Feyerabend, Imre Lakatos, Carl Hempel, Nelson Goodman, and Bas van Fraassen.

All of these thinkers responded in one way or another to logical positivism, the dominant movement influencing the philosophy of science during the first half of the 20 th century. Logical positivism attempted to ground science exclusively in what could be known through direct experience and logic.

It sounds reasonable, but logical positivism proved to be riddled with serious problems, and its eventual demise is an object lesson in how truly difficult it is—perhaps impossible—to secure the logical foundations of a subject that seems so unassailably logical: science.

A Surprisingly Practical Field

The philosophy of science can be abstract and theoretical, but it is also surprisingly practical. Assumptions about the nature of science affect such contemporary debates as:

  • Which research gets funded
  • What topics qualify as science in elementary and high school classrooms
  • What is considered legitimate and ethical medical care
  • What and whether treatments are reimbursed by insurance companies.

Science plays a pivotal role in our society, and a rigorous study of its philosophical foundations sheds light on the ideas, methods, institutions, and habits of mind that have so astonishingly and successfully transformed our world.

Philosophy Made Accessible

In 36 half-hour lectures, Dr. Kasser takes you step by step through a host of philosophical arguments that illuminate important aspects of science. His goal is "to leave you puzzled in articulate and productive ways"—a mission at which he has compiled an impressive track record, as evidenced by such honors as the prestigious Senior Class Charles Bassett Teaching Award at Colby College.

In reporting this award, Colby Magazine cited the following testimonial from a student: "Jeff makes difficult material accessible better than anyone else from whom I've taken a class. After one of Jeff's classes, students feel as though they have conducted a complete study, not just a survey of scattered ideas."

Slaying Philosophical Dragons—or Wounding Them?

One example of how even the most promising approach to science is beset with unforeseeable problems involves the favorite philosopher of many working scientists: Karl Popper. People from all walks of life are familiar with Popper's rule of thumb for separating pseudoscience from science: If a theory can't be "falsified"—if there is no way to disprove it—then it doesn't qualify as science.

Early in the course, you will learn that Popper came up with this formulation in the 1930s in response to his disillusionment with Marxist political theory and Freudian psychology. Neither discipline appeared to have the self-confidence of, for example, Einstein's relativity theory, which could unequivocally state the kinds of observations that would disprove, or falsify, it.

By contrast, Marxists and Freudians tended to argue away all apparently disconfirming evidence, rendering their theories immune to falsification. Spurred by this realization, Popper proposed that true science is engaged in a ceaseless attempt, not to prove theories (something that can never be done definitively), but to falsify them, and having done so, to move ahead to improved theories. These, in turn, undergo a new round of tests until falsified, and so on.

As you will learn, Popper's demarcation criteria seemed to slay some prominent philosophical dragons, including the notorious problem of induction, first proposed by the Scottish philosopher David Hume in the 18th century. Hume argued that there is no justification for making the inductive inference that the future will resemble the past, which is a linchpin of scientific reasoning.

For Popper, this was not a problem because his falsification criteria made no appeal to induction. Professor Kasser quips that Popper is like a mutual fund manager who warns that past performance is not only no guarantee of future performance; it's no evidence at all for future performance.

But consider these cases:

  • Contrary to Popper's model, at some point we stop testing our theories and start taking them for granted. Ask yourself how much sense it makes to get on an airplane if you don't think past performance is any indicator at all of future performance.
  • From reading Popper, you might expect that early 19th-century scientists would have been anxious to reject Newtonian physics when the planet Uranus did not have the orbit that Newtonian physics predicted. Instead, they kept Newtonian physics and posited an as-yet-unobserved planet that turned out to be Neptune.
  • Astrology is the poster child of alleged pseudosciences. But advocates of this view often say in one breath that astrology makes false predictions and in another that it's unfalsifiable and hence, unscientific. But making false predictions is just one outcome of making testable ones. You can't simultaneously reject a theory as false and unscientific, especially if your criterion for science is falsifiability.
  • Popper's criteria admit virtually all competitors into the race to survive falsification. But "nobody would watch the Olympics if everybody got to compete," says Professor Kasser. "We have to find some way of distinguishing views that should be taken seriously, that should receive our resources, from views that shouldn't."

Popper is not the only thinker to get the philosophical third degree in this manner. If you already hold views about the nature of science or if you simply have strong instincts about what sounds right, you will find your convictions tested repeatedly in this course.

A Manual for Intellectual Self-Defense

Popper represents one powerful current of philosophical thought about science in the 20th century. Another was initiated by Thomas Kuhn in his 1962 book, The Structure of Scientific Revolutions, which Professor Kasser also covers in depth.

In the course of these lectures, you will investigate a wide range of philosophical approaches to science, including empiricism, constructivism, scientific realism, and Bayesianism.

You will also explore such concepts as natural kinds, bridge laws, Hume's fork, the covering-law model, the hypothetico-deductive model, and inference to the best explanation (mistakenly called "deduction" in the Sherlock Holmes stories). Professor Kasser shows how these and other tools allow us to take apart scientific arguments and examine their inner workings.

"Philosophy, in general, is supposed to provide a kind of manual for intellectual self-defense," he explains. "So philosophy of science should help us look at claims made within science, and claims made about science, and help us make informed judgments about how and what we're to think about each case."

Throughout the course, Dr. Kasser is careful to be an impartial guide, describing the arguments among different philosophers as these debates developed during the past 100 years. In Lecture 36, he ventures his own synthesis of the major themes that stand out in this remarkable century of thought.

Dr. Kasser's masterful summary in this last lecture might just count as a game-winning play in the inquiry he launched so boldly with a baseball analogy in Lecture 1. But we invite you to be the umpire.

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36 Lectures
  • 1
    Science and Philosophy
    Does a scientific worldview leave any room for distinctively philosophical knowledge? Do philosophers have anything useful to tell anyone, especially scientists, about science? Professor Kasser argues that this course will give ample reasons to answer "yes" to both questions. x
  • 2
    Popper and the Problem of Demarcation
    The distinguishing mark of science, according to Viennese philosopher Karl Popper, is that it seeks to falsify, not to confirm, its hypotheses. This lecture develops and assesses Popper's remarkable proposal. x
  • 3
    Further Thoughts on Demarcation
    What would be the implications of describing astrology as lousy science rather than as pseudoscience? Would this treatment of the problem of separating science from pseudoscience inevitably lead to the teaching of creationism in high school classrooms? x
  • 4
    Einstein, Measurement, and Meaning
    Einstein's special theory of relativity shocked physicists and scientifically minded philosophers by revealing a lack of clarity in familiar concepts such as length and simultaneity. When we insist on understanding simultaneity and length experimentally, we see that they crucially involve the notion of a reference frame, which is why durations and lengths are measured differently by observers moving relative to one another. x
  • 5
    Classical Empiricism
    The classical tradition of Locke, Berkeley, and Hume sets the terms for the problems that a sophisticated empiricist account of scientific knowledge must address. Empiricism's antimetaphysical tendencies constantly threaten to force it into a disabling and radical skepticism. x
  • 6
    Logical Positivism and Verifiability
    Born in the early 20th century, logical positivism tried to develop an empiricist conception of philosophy that was logically coherent and adequate to the practice of science. This lecture sketches the positivist program, paying special attention to the demarcation criterion and the verification principle. x
  • 7
    Logical Positivism, Science, and Meaning
    It is difficult for empiricism to make room for unobservable reality. However, scientific theories are full of claims about quarks and other apparently unobservable entities. One response is instrumentalism, according to which a scientific theory need only "save the phenomena." x
  • 8
    W. V. Quine's "Two Dogmas of Empiricism," published in 1953, is often considered the most important philosophical article of the century. In it, Quine draws radical implications from his idea that hypotheses are not testable in isolation. x
  • 9
    Discovery and Justification
    John Stuart Mill systematized a number of techniques used in earlier empiricist approaches to inquiry. Although overly ambitious and curiously naïve by today's standards, Mill's methods have proved valuable in fields such as artificial intelligence. x
  • 10
    Induction as Illegitimate
    This lecture begins the discussion of inductive logic by wrestling with Hume's argument that there is no justification for believing that the sun will rise tomorrow. Popper claimed that this was not a problem for science, which could operate perfectly well without such inductive inferences. x
  • 11
    Some Solutions and a New Riddle
    There are several philosophical responses to Hume's problem of induction. Notably, Nelson Goodman's "new riddle of induction" turns Hume's problem on its head, showing that experience lends support to too many inferences of uniformity in nature, not too few. x
  • 12
    Instances and Consequences
    Carl Hempel offered a paradox that appears as frustrating as Goodman's, showing that almost anything counts as evidence for a proposition such as "All crows are black." This instantial model was replaced by the hypothetico-deductive model, which faced challenges of its own. x
  • 13
    Kuhn and the Challenge of History
    Thomas Kuhn's 1962 book, The Structure of Scientific Revolutions, dealt logical positivism its mightiest blow. This lecture discusses the pattern of normal science punctuated by periods of revolution that Kuhn finds in the history of science, and his explanation of this pattern via the notion of a paradigm. x
  • 14
    Revolutions and Rationality
    Kuhn's treatment of normal science is controversial, but his treatment of scientific revolutions created a greater sensation. Notions of rationality and truth play little role in his explanation of the rise of a new paradigm. x
  • 15
    Assessment of Kuhn
    Kuhn's powerful and wide-ranging work raises several questions: How accurate is his portrayal of patterns in science? How acceptable is his explanation of these patterns? Are his claims about perception defensible? How sophisticated are his views of language and truth? x
  • 16
    For and Against Method
    Imre Lakatos tried to reconcile Kuhn's historical approach with a more robust role for scientific rationality. Lakatos's intellectual sparring partner, Paul Feyerabend, argued against all scientific methodologies. If there has to be a rule governing scientific practice, Feyerabend's is: Anything goes. x
  • 17
    Sociology, Postmodernism, and Science Wars
    Sociology of science promoted itself as the heir to philosophy of science, inspiring ideas such as "the social construction of reality." This lecture also explores postmodern views of science, including physicist Alan Sokal's notorious submission of a parody essay to the journal Social Text. x
  • 18
    (How) Does Science Explain?
    This lecture explores some philosophical ideas that have come to the fore since the Kuhnian revolution, focusing on Hempel's covering-law model of explanation. Hempel tried to reconcile empiricist scruples with the need for genuine scientific explanations. x
  • 19
    Putting the Cause Back in "Because"
    Many philosophers appeal to causation to avoid problems that crop up in Hempel's covering law model, which allows arguments that intuitively have no explanatory force as legitimate scientific explanations. The causal model appears to deal with this concern. x
  • 20
    Probability, Pragmatics, and Unification
    This lecture examines the remaining major issues in the philosophy of explanation, including Bas van Fraassen's radical proposal that explanation is no part of science itself and that good explanations are nothing deeper than contextually appropriate answers to "why" questions. x
  • 21
    Laws and Regularities
    It is generally, though by no means unanimously, agreed that science seeks to uncover laws of nature. But the role of such laws is controversial. Empiricist philosophers are suspicious of the very concept because of the association of laws of nature with divine decrees and other metaphysical pictures. x
  • 22
    Laws and Necessity
    This lecture looks at several other approaches to the problem of laws of nature. Nancy Cartwright, a philosopher of physics, argues for a stark dilemma: Either the laws of nature are false, but can be used in scientific explanations; or they are true, but useless for explaining things. x
  • 23
    Reduction and Progress
    Science appears to progress when one theory is absorbed by or reduced to another. According to the positivists, bridge principles allow the reduced theory to be derived from the reducing theory. But Kuhn and Feyerabend hold that many such cases are more like replacements of one theory by another. x
  • 24
    Reduction and Physicalism
    Many philosophers have been tempted by the view that the social sciences reduce to psychology, which reduces to biology, which reduces to chemistry, which reduces to physics. What are the prospects for this bold outlook? x
  • 25
    New Views of Meaning and Reference
    This lecture explores a new approach to meaning and reference, along with a new conception of scientific theories. These ideas conceive of theories in terms of models and analogies, rather than as deductive systems. x
  • 26
    Scientific Realism
    Scientific realism is the claim that successful scientific theories correctly depict unobservable as well as observable reality. "Hard" realists seek to discover how the world truly is. "Soft" realists strive to organize a mind-independent world in the way that makes the most sense out of the many possibilities. x
  • 27
    Success, Experience, and Explanation
    Realists defend their position as the best explanation for the success of science. Anti-realists point to a number of successful-but-false theories in the history of science. Under what conditions, if any, does the success of a theory give grounds for believing it is true? x
  • 28
    Realism and Naturalism
    The realist asserts and the empiricist denies that a theory's explanatory success provides evidence that the theory is true. Many realists argue that realism is best defended from within a naturalistic approach, which abandons the project of providing a philosophical justification for science. x
  • 29
    Values and Objectivity
    This lecture examines the values that animate science and scientists. Might the social structure of science generate objective results even if individual scientists are motivated by the pursuit of recognition, money, or tenure? Who should get to participate in the formation of a scientific "consensus" and why? x
  • 30
    Throughout much of Western intellectual history, "chance" was thought to represent the enemy of reason. But notions of chance, or probability, are now arguably inquiry's greatest ally. This lecture confronts the philosophical issues that arise about the interpretation of probability statements. x
  • 31
    Bayesianism is a remarkable program that promises to combine the positivists' demand for rules governing rational theory choice with a Kuhnian role for values and subjectivity. After explaining the basics of Bayesianism, this lecture examines its approach to scientific reason. x
  • 32
    Problems with Bayesianism
    Predictably, a Bayesian backlash has also been gaining momentum in recent years. This lecture investigates Bayesianism's surprisingly subjective approach to probability assignments as well as the Bayesian treatment of the problem of old evidence. x
  • 33
    Entropy and Explanation
    Typically, philosophy of science is philosophy of a particular science. This lecture turns to the philosophy of physics to examine such concepts as the reduction of thermodynamics to statistical mechanics, the direction of time, the origin of the universe, and the nature of explanation. x
  • 34
    Species and Reality
    Biology defines species in a number of ways, and even some of the best definitions seem to exclude most organisms on Earth from being members of a species. How valid is the species concept, and does a sufficiently well-defined notion of species track something real? x
  • 35
    The Elimination of Persons?
    Folk psychology is the commonsense explanation of human behavior in terms of beliefs, desires, and so forth. Many folk psychological explanations face direct empirical challenge and are vulnerable to eliminative reduction, which has the paradoxical effect of rendering personality an illusion. x
  • 36
    Philosophy and Science
    Seeking to "leave you puzzled in articulate and productive ways," Professor Kasser sums up the overarching themes of the course, which involve recurring ideas such as the search for demarcation criteria, the inescapability of metaphysics, and the tension between empiricism and realism. x

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Jeffrey L. Kasser
Ph.D. Jeffrey L. Kasser
Colorado State University

Dr. Jeffrey L. Kasser is Assistant Professor of Philosophy at Colorado State University. He earned his B.A. from Rice University and his M.A. and Ph.D. from the University of Michigan at Ann Arbor. As a graduate student, Dr. Kasser taught Philosophy of Science to Ph.D. students in Michigan's School of Nursing. He was the first recipient of the John Dewey Award for Excellence in Undergraduate Education given by the Department of Philosophy at Michigan. While completing his dissertation, Dr. Kasser taught at Wesleyan University. He then moved on to Colby College, where he helped direct the Integrated Studies Program and received the Charles Bassett Teaching Award in 2003. Professor Kasser's dissertation concerned Charles S. Peirce's conception of inquiry. The classical pragmatism of Peirce and of William James serves as the focus of much of his research. He won the 1998 essay prize of the Charles S. Peirce Society for his essay, Peirce's Supposed Psychologism.

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Rated 4.1 out of 5 by 68 reviewers.
Rated 1 out of 5 by Worst Course Encountered at Great Courses I have advanced degrees in scientific fields and purchased this course with great interest. However, I could not even complete it as it was wasting time better spent listening to other courses. This will be the first time I will be asking for a refund. Here are some of the problems. 1. The way this course is presented has nothing to do with teaching. The presenter appears to be reading from a manuscript and at a speed far too fast for the complexity of the material he is presenting. Furthermore, he drones on and on in a monotone as a result of this technique. It is most definitely not the style used in active classroom teaching. If he was forced to diagram some of his statements on a blackboard, he might do better. 2.The early lecture, on the "Demarcation Problem" i.e., telling science from pseudo-science, is a classic example of what I term philo-babble. Philo-babble is an attempt to carry on extended discussions, often reaching startling results, about a subject that is never defined. In this case, the presenter tries to talk about what is real science without ever defining what science is ! Unfortunately, the failure to define science infects most of the lectures as well. These "language games" were identified by Wittgenstein long ago. 3. The presenter's prose is very dense, full of qualifiers, and soon becomes mostly unintelligible, at times resembling a "word-salad". You will frequently ask yourself " What on earth is he talking about ?" 4. The examples used are absurd and involve things such as dragon's and invented terms. The best he can do with actual real world science is Copernicus, Kepler, plus a little Newton and Einstein .There is no real treatment of current problems crying for philosophical analysis, such as string theory and quantum mechanics. February 22, 2015
Rated 3 out of 5 by Opportunity Unfulfilled The Philosophy of Science can be a broad, interesting and an impactful field of concern. The opportunity for this course was wide open to craft, out of the wealth of material available for presentation, a far ranging examination of the framework of science. Unfortunately this opportunity wasn’t fulfilled. Professor Kasser is a engaging lecturer and would like to see him in another course that would better showcase his talents. One of his observation I particularly enjoyed is: “Philosophy is the art of asking child-like questions and then using the methods ad arguments of lawyers to find answers.” Be warned or encouraged! The scope of this course is narrowed to looking at only a small slice of the picture 20th century logical positivism, its’ challengers; Scientific realism and its’ challengers, and some of the other more recent attempts developments among some academic philosophy practitioners. Well this may be a good approach if the audience is primarily philosophy students well versed in range of philosophical examinations of science, for others, including those with a background in science as it is practiced, and without a strong philosophical background, as well as those who are starting at the beginning of study of Philosophy of Science, an opportunity for learning is left unfulfilled. The course seems to have a bias against mathematics, a language used to communicate and validate in science including an unclear understanding of p-values use in evaluating research findings, and not the best understanding of science as it is practiced. As such, it doesn’t fulfill the potential of the course, even with such a limited scope. If you are not well-versed in philosophical minutiae and informed about the development of the Philosophy of Science up to the 20th century, this may not be the best place to start your search and learning. I hope that TGC adds a more general and inclusive Philosophy of Science course that addresses some of the concern expressed in a number of reviews to better communicate an important field to a wider audience of learners. December 7, 2014
Rated 5 out of 5 by The best Teaching Company course I've taken I recently completed Dr. Kasser's Philosophy of Science course and found it to be outstanding. He is articulate, funny,and never dumbs down the material too much, despite the fact that some of ti can be quite complicated. September 30, 2014
Rated 4 out of 5 by A Great Overview of the Subject This course was just what I hoped it would be: an eloquent, fair-minded, impressively comprehensive, eye-opening introduction to a subject I've recently become fascinated by, and that I wish more people were familiar with (given the role of science in many of our most significant social & political disputes#. I found Professor Kasser to be a congenial, articulate and sometimes witty instructor #though, on occasion, he appeared a bit flustered -- but that happens to a lot of us). It introduced me to a lot of new material that has expanded my thinking about science. September 26, 2014
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