Cognitive Psychology - Inductive and Deductive Reasoning

, Deductive vs. Inductive Reasoning

Deductive reasoning  Facts
 Essential details to make a reasoned decision present
Inductive reasoning  Less structured
 Conclusion may not follow on from the premises

 Do not directly consider validity as in deductive argument

 Instead look at STRENGTH of argument:
- STRONG argument – decide that conclusion = true
- WEAK argument – decide that the conclusion = not true

 Inductive argument gives us the basis to say whether the
conclusion is probably true vs definitely true
 Number of factors  Contribute to perceived strength of an
inductive argument:
- Representativeness of Observations: how well do your
observations match with previous ones
- Number of Observations: More observations strengthen a
conclusion
Fewer observations = weaker the conclusion
- Quality of Evidence: Sound obvious, but the stronger the
evidence – stronger the argument – stronger the conclusion

Inductive reasoning in Everyday Life
 Use inductive reasoning to guide us through any number of
conclusions that refer to past experiences or events
 Consider these two examples:
 On a module that you are taking with Dr. X you observe that
he/she
asks a lot of questions about experimental methods in the
final exam
- Based on this observation, would conclude that exams for
other of Dr. X’s courses would be very similar in content
 You buy something from a mail order company & get good
service –
you therefore place another order with the same company
based on an
observation of previous good service
 Make any number of predictions about what will happen
based on what
has happened previously
 Great deal of common sense surrounding the specifics of
inductive reasoning
 Make choices & predictions based on our past experiences &
events



2