Philosophy of Science

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Philosophy of Science
University of Oulu, March 4-6, 2009
Sami Pihlström (Professor of Practical
Philosophy, University of Jyväskylä,
sami.j.pihlstrom@jyu.fi,
sami.pihlstrom@helsinki.fi)
Course program
• Wed, March 4: What is science? The scientific
method. The aims and goals of science.
Naturalism and relativism.
• Thu, March 5: The issue of scientific realism.
Introducing pragmatist philosophy of science (in
relation to the realism issue and generally).
• Fri, March 6: Pragmatism (and its history) in the
philosophy of science. Science and values,
science and religion, etc.
– The participants can present their own brief papers,
discussing their own research problems and
methodology from a philosophical perspective.
What is science?
• ”Science” (”Wissenschaft”, ”tiede”, ”scientia”):
– the scientific community
– the research process
– the results/contents of scientific research (the scientific
worldview)
• ”Science is systematic, rational acquisition of new
knowledge.” (Haaparanta & Niiniluoto)
– What is (new, previously unknown) knowledge? (the classical
conception of knowledge: justified true belief)
– What is rationality (in science and elsewhere)?
– What is systematicity (in science and elsewhere)?
• E.g., ontological, logical, explanatory, institutional, etc. – different
dimensions of scientific systematicity.
Perspectives on science
• Science (and Technology) Studies (STS):
interdisciplinary, empirically informed research on the
nature of science, including history, sociology, and
philosophy of science (and technology).
– What exactly is the relation between science and technology?
• Philosophy of Science: normative vs. descriptive (factual,
empirical).
– The philosopher of science doesn’t merely describe facts about
science but tries to determine what science ought to be like. (Cf.
the normativity of epistemological theories of knowledge and
justification, etc.: epistemology is not just concerned with the
ways we actually form beliefs but with how we ought to form and
justify our beliefs.)
Philosophy of science and other
areas of philosophy
• Problems in the philosophy of science are deeply
connected with other philosophical problems, e.g.:
– Metaphysics: do the objects of scientific research exist
independently of us (and of scientific theories, etc.)? (The
problem of realism.)
– Epistemology: what is scientific knowledge? (Philosophy of
science can be seen as the application of general epistemology
to the special case of scientific knowledge.)
– Logic: what is (valid) scientific inference like?
– Philosophy of language: do scientific theories (theoretical terms
and concepts) refer to independently existing entities, and are
theories true or false (in the correspondence sense)?
– Ethics and political philosophy: is science value-free or valueladen; what kind of ethical and social problems do science
involve?
– Philosophy of religion: does science refute religion?
Philosophy of science:
general and special
• General philosophy of science: problems common to all
scientific disciplines (including the humanities): truth,
inference, explanation (vs. understanding), etc.
• Special problems in relation to different scientific
disciplines, e.g.:
– Philosophy of mathematics: do mathematical entities exist, what
is mathematical truth?
– Philosophy of physics: time and space, the interpretation of
quantum theory?
– Philosophy of biology: the nature of life, the reality of species?
– Philosophy of history: the reality of the past, the determinacy of
the truthvalues of claims about the past, historical explanation?
– Philosophy of education: the scientific worldview and education,
the science vs. religion issue, etc.?
The aims and goals of science
• Cognitivism: Science
aims at knowledge and/or
truth about the world
(classical definition of
knowledge as justified
true belief).
– Truth (knowledge) is
valuable as such, for its
own sake (intrinsic value).
– Cf. scientific realism:
there is a world out there,
independently of us, and
science aims at finding out
what it’s like.
• Behavioralism: Science
aims at practical
recommendations and
problem-solving.
– Knowledge and truth are
not sought for their own
sake.
– Instrumentalism:
knowledge has only
instrumental value, not
intrinsic value. (N.B. In a
more specific sense,
instrumentalism denies that
scientific theories have
truthvalues.)
Basic and applied research
• A moderate cognitivist admits that knowledge can be
instrumentally valuable and applicable to practical
problem-solving, even though the primary motivation for
seeking knowledge is not instrumental but, e.g., pure
intellectual curiosity.
• Basic research: knowledge/truth for its own sake.
– Scientists aim at true (or truthlike) theories about the way the
world is.
• Applied research: instrumentally valuable knowledge,
applicable to practical problems.
– Applying the results of basic research, scientists aim at workable
solutions to various problems we face in our practices.
– ”Design science” (Niiniluoto): designing a solution to a practical
problem, etc.
Science and human interests
• Jürgen Habermas: natural science is motivated by a
technical interest (governing nature), the human
sciences by a hermeneutical interest (understanding),
and critical social theory by an emancipatory interest
(liberating humans from domination structures, etc.).
– Background: Frankfurt School cultural critique, the ”dialectics of
the enlightenment” (Adorno, Horkheimer).
• Is ”pure” natural science independent of technical
domination of nature possible at all?
– A major issue in science and technology policy. Should scientific
research simply be seen as a tool for business, and society in
general?
– The value-ladenness vs. value-independence of scientific
research (we will return to this problem in due course).
Applied research
• Typically, the results of applied research are not
theoretical statements about the way the world is (as in
basic research) but ”technical norms”: if you want to
achieve goal X, then you ought to do Y (cf. von Wright
1963).
– If you want to cure a patient with an infection, you ought to use
antibiotics.
– If you want to achieve maximum destructive potential for your
nuclear bomb, you ought to build it like this…
• N.B. The interests upon which the technical norms arrived at in
applied research are based are not morally neutral! There is always
room for valuational discussion of what kind of interests we ought to
pursue, and why.
– Technical norms have truthvalues: they are true or false
statements about the relations between aims and the means
necessary for achieving those aims.
Applied research (continued)
• We might consider the relation between basic and
applied research in, e.g., the following scientific
disciplines:
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Medicine
Agricultural science
Education
Political science
History (of ideas)
Aesthetics (and art education) …
• Is it always possible to draw a clear distinction between
basic and applied research? Sometimes, even the most
”basic” research problems might be motivated by the
potential applicability of the results of research.
Science and technology
• Some etymology: episteme (knowledge) vs. tekhne (skill).
– Technology: tekhne + logos, ”the study/doctrine of skills”.
• Is technology just applied science, or the construction of
applications based upon applied research? Or is
(contemporary) science crucially dependent on technology?
– Science (today) necessarily requries a technological
context.
– Tecnology can be understood very broadly (cf. John
Dewey, Larry Hickman): any tools intelligently used to
promote human purposes are technological – including,
e.g., language.
• Philosophy of technology studies the nature of our
technological culture. Technopessimism (Heidegger) vs.
moderate optimism, meliorism (Dewey, Hickman).
• Science and technology studies: taking seriously the
technological context of modern science. Normativity?
The scientific method
• When is research scientific? What is the definition of, or
the criteria for, ”the scientific method”?
• Is there such a thing as the ”scientific method”?
• The problem of demarcation (Karl Popper 1934): how to
demarcate between science and pseudo-science (e.g.,
metaphysics – cf. logical empiricism, the Vienna Circle)?
– N.B. Pseudo-science must not be confused with non-science.
Clearly non-scientific human practices, e.g., art or sport, are not
pseudo-scientific, whereas practices/”disciplines” like astrology,
graphology, creationism, spiritual healing, anthroposophy, etc.,
are usually taken to be.
– Not everything must be made scientific, but practices/disciplines
that do not fulfill the criteria for scientificity should not pretend to
be scientific.
The scientific method (cont’d)
• Is there a single correct scientific method (the
scientific method), or are there several?
– Methodological monism (or methodological optimism):
there is only one correct scientific method, and it can
be discovered (cf. logical empiricism, the unity of
science movement).
– Methodological pluralism: there are several different,
equally correct scientific methods (e.g., reflecting the
differences of various disciplines, such as the natural
and the human sciences).
– Radical pluralism: methodological anarchism (Paul
Feyerabend: ”anything goes!”) – cf. relativism.
The scientific method (cont’d)
• Charles S. Peirce, ”The Fixation of Belief” (1877): four
different ways of fixing beliefs about the world.
• (1) the method of tenacity
• (2) the method of authority
• (3) the method of what is agreeable to reason (the
intuitive method, the a priori method)
• (4) the scientific method
– A criterion for reality: independence of what any number of
persons may think, hope, etc.
– Our beliefs should be fixed by an ”external permanency”.
– Yet, the world may not be independent of ”thought in general”.
– We’ll return to the issue of realism within pragmatist philosophy
of science (which Peirce founded).
The scientific method (cont’d)
• On the basis of Peirce’s (and others’) reflections on the
scientific method, we may emphasize the following
”corner stones” of scientific rationality (among others):
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–
–
–
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Objectivity
Publicity
Critical thinking
Self-correctiveness
Autonomy
Progressiveness
• Problem: who is supposed to set these criteria, from
which perspective, on what grounds? Is this the task of
the philosophy of science, or of the scientific community
and/or research process itself?
– Traditional (autonomous) vs. naturalized philosophy of science!
Naturalism and relativism
• Naturalism: ”there is no first philosophy” – no
autonomous philosophical perspective over and above
science itself (W.V. Quine).
• Rather, science and philosophy (of science) must be
seen as continuous with each other.
– The problem of circularity: if science itself, instead of any prior,
more fundamental philosophical theory of the nature of science,
establishes its own normative criteria, does it have any
foundation at all?
– How does this situation differ from, e.g., the religious
fundamentalists’ claim that the Bible establishes its own authority
as a sacred text?
• Naturalism challenges the traditional normative nature of
the philosophy of science: the norms of scientific
research cannot be established from outside science.
From naturalism to relativism?
• We may sketch the following loose argument:
• (1) Naturalism: there is no first philosophy that could
normatively determine what science is, or what it ought
to be, from a perspective lying outside science itself.
(Premise.)
• (2) Therefore, science itself determines its own criteria.
In particular, the problem of demarcation (between
science and pseudo-science of metaphysics) can be
settled only science-internally; if understood as a general
philosophical problem, it is a mere pseudo-problem.
(Follows from (1). The structure of the argument could
be made more explicit by adding the premise that the
criteria of science can only be settled either scienceinternally or science-externally.)
From naturalism to relativism
(cont’d)
• (3) There is no ahistorical criterion, independent of the historical
phase of the development of science (or a particular scientific
discipline), for determining what is (good, proper, correct) science.
(Follows from (1) and (2), at least by adding the obvious premise
that science is a historically developing phenomenon.)
• (4) There are, in the history of science, radically divergent stages
with very different conceptions of the criteria of (good, proper,
correct) science and of the science vs. pseudo-science demarcation.
(Premise, a historical statement of fact. Cf. Thomas S. Kuhn:
paradigms, scientific revolutions.)
• (5) Therefore, we must accept relativism: the criteria of science (and
demarcation) are relative to the historical stage of science (or a
particular scientific discipline), a (Kuhnian) paradigm, a perspective
or point of view, a tradition, a local scientific community, a culture, a
social context, or some other ”background” that makes it possible for
scientists to pursue their disciplines. (Follows from (3) and (4).)
From naturalism to relativism
(cont’d)
• The argument above is not strictly deductively valid but
can easily be transformed into a more explicit,
deductively valid argument by adding relatively obvious
premises.
• It seems that relativism follows from the naturalist denial
of there being any foundational ”first philosophy” which
would determine the normative criteria of the scientific
method.
• Challenge: is there a middle ground option available, a
moderate form of naturalism with no radically relativist
consequences? (We’ll examine this issue in relation to
pragmatist philosophy of science.)
Forms of relativism
• Moral relativism
• Cognitive relativism
– Conceptual (ontological) relativism
– Perceptual relativism (cf. the theory- and concept-ladenness of
observation)
– Alethic relativism (relativism about truth)
– Logical relativism (relativism about valid inference or the criteria
of rationality)
– …
• No exhaustive survey of different relativisms is possible
here. Nor am I implying that moral and cognitive
relativisms would always be easily distinguishable.
• ”Relative to…” – culture, paradigm, conceptual
scheme…
Examples of relativist philosophy of
science…
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… or of overhasty accusations of relativism?
W.V. Quine: ontological relativity
T.S. Kuhn: paradigms, incommensurability
P. Feyerabend: anarchism, ”anything goes”, ”against method”
R. Rorty: radical neopragmatism, ethnocentrism
A. Fine: natural ontological attitude (NOA)
All these (very different) approaches – in the philosophy of
science and elsewhere – risk losing trans-cultural and transparadigmatic normativity, but none are clearly examples of
radical relativism; on the contrary, these thinkers typically
deny that they are relativists!
– Even Feyerabend rejects relativism, because ”potentially every tradition
is all traditions”.
– Accusing someone of relativism is always problematic, contextual.
– The reflexive charge (cf. Plato): is relativism merely relatively true?
Naturalism and relativism
(summing up)
• The problem of relativism is a constant challenge in the
philosophy of science, especially naturalized philosophy
of science rejecting traditional ”first philosophy”. It cannot
be avoided; nor should we simply succumb to relativism.
• Naturalists are right to reject any absolutely autonomous,
science-external ”first philosophy”, but they risk
sacrificing normativity and ending up with (radical)
relativism.
• We must continuously seek the middle ground: a
normatively adequate naturalism, a form of naturalism
which doesn’t give up (but merely reinterprets or
reconceptualizes) the traditional normative task of the
philosophy of science.
Pragmatist philosophy of science
• Pragmatism is one tradition in the philosophy of
science (and philosophy more generally) that
hopes to offer such a middle ground.
• Classical pragmatist philosophers (of science):
– C.S. Peirce – the scientific method
– William James – perhaps more important in other
fields (e.g., philosophy of religion)
– John Dewey – naturalist, experimentalist theory of
inquiry
– G.H. Mead – pragmatism and the social sciences
– Neopragmatists: Rorty, Hilary Putnam, et al.
Pragmatism, truth, and
the goals of science
• Can pragmatists accept (moderate) cognitivism – ”science aims at
truth” – or must they abandon the idea that science is a truthseeking activity?
– Rorty: truth is not a goal of inquiry. (Truth vs. justification.)
• Again: normative vs. descriptive question: has science been, or
should it be, a truth-seeking activity; have pragmatists believed it to
be, and should they have?
• Rorty’s ethnocentrist neopragmatism (”we have to start from where
we are”) is in the danger of collapsing into radical relativism, with no
room for trans-cultural normativity, and thereby with no resources to
distinguish, even contextually, science from pseudo-science.
– Rorty seems to reduce epistemic (scientific) justification to mere
local justification for a particular scientific community (we have to
start from where we are…).
– Even Rorty will have to use normative concepts!
Pragmatist philosophy of science
(cont’d)
• Some advantages of pragmatism (to be
discussed in more detail later):
– Moderate naturalism: science is part of the natural
world, along with everything else.
• No sharp nature vs. culture dichotomy.
• Normativity can be maintained (”second nature” for us, as the
kind of natural beings we are – cf. John McDowell).
• Emergence?
– Antireductionism, pluralism: no ”unity of science” but
the plurality of perspectives, standpoints, and
worldviews (cf. W. James’s pluralistic pragmatism:
science, ethics, religion, … all relevant to human
concerns).
Pragmatist philosophy of science
(cont’d)
• Advantages of pragmatism (cont’d):
– Transcending the realism vs. antirealism opposition: a
pragmatic realism as a synthesis of scientific realism
and its (constructivist, relativist) alternatives (cf.
Putnam)?
• The realism issue will, in the following, be adopted as the
main philosophical context for the defense of a pragmatist
approach in the philosophy of science.
– Taking seriously the socio-historical (including
technological) contexts of science and inquiry (cf.
Dewey, Hickman, et al.).
• Perhaps even Kuhn can be interpreted as a pragmatist?
Pragmatist philosophy of science
(cont’d)
• Pragmatism, however, also has its problems:
– Is the pragmatists’ way of going beyond the realism
vs. antirealism controversy successful, or does it
collapse back to idealism, constructivism, relativism,
or something else? (Cf. Kant’s transcendental
idealism.)
– How can we adequately articulate the practiceinternal normativity (of science) pragmatists insist on?
– There is no short cut to avoiding the problems of
relativism and naturalism. Even pragmatist philosophy
of science must continuously re-examine its own
starting points and conditions of possibility, in critical
dialogue with other approaches in the philosophy of
science.
Suggested reading
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Dewey, J. (1929), The Quest for Certainty, Finnish translation by P.
Määttänen: Pyrkimys varmuuteen, Gaudeamus, Helsinki, 1999.
Feyerabend, P. (1975), Against Method, Verso, London.
Fine, A. (1996), The Shaky Game, rev. ed. (1st ed. 1986), The University of
Chicago Press, Chicago.
James, W. (1907), Pragmatism, Harvard UP, Cambridge, MA, 1975. (The
Works of William James, 19 vols, Harvard UP, 1975-88.)
Kuhn, T.S. (1970), The Structure of Scientific Revolutions, 2nd ed. (1st ed.
1962), The University of Chicago Press, Chicago.
Niiniluoto, I. (1999), Critical Scientific Realism, Oxford UP, Oxford.
Peirce, C.S. (1931-58), Collected Papers, 8 vols, Harvard UP, Cambridge,
MA.
Peirce, C.S. (1992-98), The Essential Peirce, 2 vols, Indiana UP,
Bloomington.
Pihlström, S. (1996), Structuring the World, Acta Philosophica Fennica 59,
Helsinki.
Pihlström, S. (2003), Naturalizing the Trascendental, Humanity/Prometheus
Books, Amherst, NY.
Suggested reading (cont’d)
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Popper, K.R. (1959), The Logic of Scientific Discovery (1934), Routledge,
London.
Popper, K.R. (1963), Conjectures and Refutations, Routledge, London.
Putnam, H. (1990), Realism with a Human Face, Harvard UP, Cambridge,
MA.
Putnam, H. (1995), Pragmatism: An Open Question, Blackwell, Oxford.
Putnam, H. (2002), The Collapse of the Fact/Value Dichotomy, Harvard UP,
Cambridge, MA.
Quine, W.V. (1969), Ontological Relativity and Other Essays, Columbia UP,
New York.
Quine, W.V. (1995), From Stimulus to Science, Harvard UP, Cambridge,
MA.
Rorty, R. (1979), Philosophy and the Mirror of Nature, Princeton UP,
Princeton, NJ.
Rorty, R. (1982), Consequences of Pragmatism, Harvester Press, Brighton.
Rorty, R. (1998), Truth and Progress, Cambridge UP, Cambridge.
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