☕️ Wason selection paradox

☕️ Wason selection paradox#

⏱ | words

Mathematics relies on rules of logic
Yet, for human brain applying mathematical logic may be difficult, and dependent on the domain

Peter Cathcart Wason (1924 – 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?

Let’s 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 \(P \implies Q\).