reasoning 2 Flashcards
what is the Wason Selection Task
Devised by Peter Wason (1966)
Used to study performance on conditional reasoning propositions/arguments/problems
Comprises 4 playing cards:
Two cards each showing a vowel or a consonant
Two cards each showing an odd or even number
Conditional proposition (if P then Q):
e.g., If a card has a vowel on one side of it, then it has an even number on its other side
Participants asked:
Which two cards must be turned over to discover whether the following rule is true?
Rule: If a card has a vowel on one side of it, then it has an even number on its other side
Choice of cards determines performance
performance on original WST
Typical results:
~ 70% of participants choose ‘E’ and ‘4’ cards
‘E’ and ‘4’: Correct (logical) choice? = No
Conditional inference component per card:
‘E’ = P; ‘K’ = not P; ‘4’ = Q; ‘7’ = not Q
why are logically valid cards often not chosen in WST
Tend to choose cards that confirm proposition’s rule (‘if P then Q’) (Wason, 1966)
‘Confirmation bias’ (Wason, 1966)
Tendency to prefer to look for evidence that confirms (not disconfirms) beliefs, theories and hypotheses
why was there poor performance on original WST,
and how was it adapted
Poor performance on original WST due to its abstract content and lack of context (Manktelow, 1999/2012, Chapter 4)
Majority of participants made logically valid card choices for conditional propositions concerning laws, rules or everyday events (see Evans & Over, 1996)
what’s the drinking age version of the WST
Rule: If a person is drinking beer (P), then they must be over 18 (Q)
Which 2 of the following 4 cards must be turned over to check truth of this rule?
Each card has a drink on one side and an age (in years) on the other side (beer, coke, 16, 22)
drinking age version results
Results: most (~ 90%) participants chose logically correct cards most of time (~ 90%)
‘Beer’ and ’16’ (‘p’ and ‘not q’) cards should be turned over to establish truth of ‘rule’ (proposition)
Why did logical reasoning improve?
People are familiar with real world rules and laws, so can reason correctly about propositions that involve them (Evans & Over, 1996)
what is negation
when the propositions involve “not”
results of Wason (1965) Sentence Verification Task
Participants slower at drawing correct (logical) or incorrect (non-logical) conclusions for propositions/arguments involving negative than positive statements/elements
Reasoning about alternatives is cognitively-taxing?
why is negation more challenging to deal with
more cognitively taxing
Hard to reason about negation in arguments because need to consider alternatives to premises and conclusion of arguments
Make inference about link between truth and falsity of elements of proposition/argument
what is rationality
Thinking consistent with, or based on, logic
Concerns methods not outcomes of thought
How we reason, not what conclusions we draw
Rationality not same as accuracy
Irrationality not same as error or bias
Accuracy and bias/error are outcomes of thinking
what is bounded rationality
Theory to explain rationality given *cognitive (and external?) *constraints
*e.g., limited working memory capacity
Our reasoning is, to some extent, rational
e.g., we try to make informed judgements
But, we don’t have cognitive resources to understand everything we encounter
Simon (1957): bounded rationality
reasoning considered rational if it violates normative standards (e.g., logic) but achieves personal goals
Given cognitive and external constraints (e.g., time pressure), our reasoning still allows us to function pretty successfully in the world
what are the 2 systems of rationality
System 1: reasoning according to achieving one’s goals and meeting one’s needs
System 2: reasoning according to normative standards
e.g., logic
Systems distinct, but can be used together
what is system 1 of rationality
Goal-directed rationality
Rational reasoning that serves everyday needs
Rapid, automatic (often pre-conscious) process influenced by beliefs, background knowledge, prior experience and learning
e.g., taking quickest route home from work
Rational in achieving one’s goals, but doesn’t conform to principles of logic
what is system 2 of rationality
Rule-based rationality
Rational reasoning that conforms to principles of logic
Slow, deliberative, conscious process linked with complex cognition (e.g., task planning, hypothetical thinking and counterfactual thinking)
