Theoretical Issues in Psychology
Philosophy of Science
and
Philosophy of Mind
for
Psychologists
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Aims of the book


Review of basic ideas and problems in
philosophy of science and philosophy
of mind, relevant for psychologists.
Psychology as science of mind:
• what is science?  Chapters 1–5.
• what is mind?  Chapters 6–10.
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Chapter 1
Science: why and how?
• Why science?
• Knowledge
• Arguments
• Laws, theories, models and causes
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Why and how?
Demarcating science:
• science as arbiter of objectivity and truth;
• demarcating science from pseudoscience;
• science as safeguard against propaganda and
superstition.
Objectivity vs subjectivity or human construction:
• realism, foundationalism, objectivism (positivism Ch. 3).
• relativism (social constructionism, sociology of science
Ch. 4 and 5).
But what defines science?
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What defines science?
• Reduction: underlying causal structure explains
macro-phenomena; this research produces …
• Unification; and promotes …
• Systematicity.
• Critical attitude: against authority and dogma;
inspires freedom of thought, advances enlightenment
and …
• Open-mindedness.
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Theories of truth
Traditional theories of truth:
Correspondence theory of truth
Coherence theory of truth
‘Recent’ theories of truth:
Consensus theory of truth
Pragmatic theory of truth
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Correspondence theory: a statement or belief
is ‘true’ if it corresponds with a situation,
an event or an object in reality, or in the world
(realism – objectivism)
‘There is a cat
on the mat!’
=>
correspondence
Coherence theory: a statement or belief is
called ‘true’ if it is coherent with other beliefs
(knowledge) that one
has (idealism / relativism)
coherent
‘There is a cat!’
with
‘A cat is a mammal of
the genus Felix;
a pet animal,
with a soft skin,
that likes to be carressed
etc., etc.’
‘Recent’ theories of truth
• Consensus theory: ‘truth’ is a social
or cultural consent or approval
(relativism / social-constructionism)
• Pragmatic theory: a belief or theory is ‘true’ or
reliable if it has success in practice; if it can be
established by experience (experiments)
Views on world & knowledge
Realism:
• world exists knower-independent;
• world is primary;
• knowledge pictures the objective world (representing);
• truth is correspondence between knowledge and world.
Relativism (an extreme version: Idealism):
• world is (partly) constructed by the knower (subject);
• subject is primary;
• knowing is constructing;
• truth is coherence with the rest of knowledge, or consensus.
Pragmatism:
• knowledge is functional and active, coping with the world;
• truth is practically, experientially successful.
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A problem for realism: ‘God’s eye view’
How to compare the world with a theory, since one can
never get outside one’s theory (opinion)? Irony: only in
‘God’s eye’ can correspondence be assessed.
OK
!
World
correspondence
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Pragmatic realism
Hillary Putnam (‘pragmatic realism’): ‘the mind
and the world jointly make up the mind and the
world’ (cf. Kant)
World
features
‘World’
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Categories,
interests
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Everyday knowledge and science
Eddington’s ‘Two Tables’:
• molecules, empty, weightless, colorless;
• visible, solid, colored everyday object.
What is the real table? Everyday world as illusion?
Everyday knowledge and scientific knowledge:
• ‘manifest’ vs ‘scientific image’ (Sellars);
i.e. visible vs underlying, explanatory image
(bv. water – H2O; depression – dopamine)
Conclusion: different perspectives, both real
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Characteristics of science
1.
2.
3.
4.
5.
6.
Systematicity: a coherent system of theories,
statements, formulae etc.
Well-defined methods: methods specify what counts
as legitimate problems, facts, solutions, etc.
Reduction: phenomena (or theories) are explained by
underlying lower-level mechanisms (or laws).
Objectivity: in the sense of being controllable, reliable
and inter-subjectively observable.
Clarity: scientific statements are phrased
unambiguously, in principle addressed to the public
domain.
Revisability: scientific knowledge is open, revisable at
all times and never definitive.
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Induction, deduction, abduction
Induction: from individual observations to general statements.
No logical certainty, but new knowledge.
Example: Lots of swans were observed; all were white.
Maybe all swans are white.
Deduction: from general statements to individual.
Logical certainty: conclusion contained in premises, but no
new knowledge.
Example: All humans are mortal.
Socrates is human.
Therefore, Socrates is mortal.
Abduction: inference to the best explanation.
No logical certainty, new hypothetical knowledge about
causes
Example: All CJD patients ate beef.
Beef may be the cause of CJD.
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The problem of induction
• Every generalisation can be disconfirmed by an
unexpected observation (‘black swan’).
• Confirmation cannot, unlike deduction, be formalised; no
logical certainty.
• Inducing requires classification; one has to start with
concepts and criteria (e.g. for similarity).
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Facts and theories
• Facts: no such thing as pure observation; theory
influences observation – ‘theory-ladenness’
• Theory (coherent set of statements) indispensable:
• standard terms for description;
• coherent, unifying;
• ‘unobservable’ scientific concepts (e.g., energy,
IQ) connected to observations by theory.
• Strict distinction between fact and theory
impossible; hierarchy from factual to theoretical.
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‘Justification’ vs ‘discovery’
Context of justification: normative, focus on method;
prescribing criteria for holding a theory true, acceptable
or justified, logically or empirically ( positivism).
Context of discovery: description of the historical, social
and psychological circumstances and influences that
were relevant to the invention or discovery of scientific
theories: who, where and when? ( more or less
relativistic views of science).
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