βοΈ Wason selection paradox#
β± | words
Mathematics relies on rules of logic
Yet, for human brain applying mathematical logic may be difficult, and dependent on the domain
![_images/wason.png](_images/wason.png)
Peter Cathcart Wason (1924 β 2003)
cognitive psychologist at University College, London
pioneered the psychology of reasoning
The Wason selection task
Given four cards showing 3, 8, blue and red faces, which
cards have to be flipped over to ensure the rule
if card shows even number on one side, the other side is blue
is satisfied?
Letβs play Wason Selection Task at Mentimeter
Analysis of Wason selection task
Let \(P\) denote
card shows even number on one side
Let \(Q\) denote
the side is blue
Numbver |
Color |
\(P\) |
\(Q\) |
Rule is satisfied |
---|---|---|---|---|
Even |
Blue |
True |
True |
Yes |
Even |
Red |
True |
False |
No |
Odd |
Blue |
False |
True |
Yes |
Odd |
Red |
False |
False |
Yes |
the rule we are checking is \(P \implies Q\)
it is only broken in case \(P\) is True and \(Q\) is False
therefore the two cards that have to be flipped are
Even, \(P\) is True
Red, \(Q\) is False
Definition
\(\implies\) denotes logical implication:
If whenever logical statment \(P\) is true, \(Q\) is also true, we write \(P \implies Q\).
Further reading and self-learning
Each lecture will suggest some material for further reading and learning
YouTube video on Wason selection task