Critical Thinking: The Art of Reasoning
Lecture 14: Inductive Arguments
© Critical Thinking Skills BV
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Example
Definition
Types (inductive argument patterns)
What goes wrong?
Learn more
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Generalisation
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Inductive Arguments
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Definition: Inductive arguments are
those involving some kind of
extension, generalisation or
extrapolation to new cases
i.e., extrapolation from “source” cases
to “target” cases
Based on an assumption of similarity
between source and target
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How NOT to define “inductive
argument”
Inductive reasoning is often defined as
reasoning which does not (like
deductive argument) guarantee the
contention
i.e., inductive = not deductive
However, this makes the concept of
inductive almost useless.
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Great variety in non-deductive arguments
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Three inductive argument
patterns
1.
(Inductive) Generalisation
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2.
Statistical Syllogism
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3.
Particular case(s) to general claim
General claim to particular case
Analogical argument
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One particular case to another
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Inductive Generalisation
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Extrapolation from a
“sample” (source) to a
“population” (target)
containing that sample
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Statistical Syllogism
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Just like classic syllogism but with a
“statistical” generalisation as the main
premise.
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Statistical Syllogism – General
Pattern
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Extrapolation from a
population (source) to a
member of that
population (target)
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Analogical Argument
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Extrapolation from
one particular case
(source) to another
(target)
Based on similarities
between the two
cases.
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Analogical Argument –
General Pattern
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How inductive arguments go
wrong
The primary way inductive arguments
go wrong is failure of similarity
between source and target
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Inductive generalisation – sample not
“representative” of population
Statistical syllogism – target case atypical
Analogy – the two cases not similar in relevant
respects
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To learn more…
See also the lesson on Fallacies, the
Reasoning for Knowledge Exercises site in
Rationale and the Rationale WIKI.
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Probability & Statistics
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Scientific Method
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Giere, Understanding Scientific Reasoning
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