Philosophy of Science
Overview
About
01: 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.
02: 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.
03: 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?
04: 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.
05: 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.
06: 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.
07: 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."
08: Holism
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.
09: 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.
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.
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.
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.
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.
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.
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?
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.
17: Sociology, Postmodernism, and Science Wars
Sociology of science promoted itself as the heir to philosophy of science, inspiring ideas such as "he 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."
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.
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.
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.
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.
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.
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.
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?
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.
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.
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?
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.
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?
30: Probability
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.
31: Bayesianism
"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.
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.
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.
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?
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.
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.