 Psychologists use scientific reasoning strategies  These strategies can be helpful outside of this class * Many of the points in this presentation are based on Keith Stanovich’s book, How to Think Straight About Psychology.

 Opinions are interesting, but they don’t provide a good way to settle disputes  Let the data do the talking  Examples: Lunar madness Implicit egoism

 Testimonials and anecdotes do not provide good evidence  Reliability  Internal validity  External validity

 There must be some way to test a claim for it to be falsifiable  Theories that explain every possible outcome explain nothing  Examples: Freudian personality theory Maslow’s hierarchy

 As in other science, evidence is probabilistic, not absolute  Need to tolerate ambiguity  Accurate prediction in long run, not individual cases

 Scientists can never be 100% certain  Support for a claim varies on a continuum from weak to strong  Extraordinary claims require extraordinary evidence ESP Subliminal perception

 Psychologists evaluate ideas operationally: define variables by describing how they are measured  Philosophers (and others) rely on essentialism: what is the true meaning?  Example: What is intelligence?

 Most things are not caused by single factors acting alone  Multiple causation  Interaction of factors  Example: conformity under some situations but not others

 Use and apply psychological research  Don’t get influenced by bogus claims  Tolerate and appreciate uncertainty