To show that humans are capable of

formal reasoning at all, Griggs & Cox (1982) devised a version of the Wason selection task which uses a

real-world example instead of an abstract task.

Again, you are presented with four cards (shown below). Each of them has the name of a

drink on one side, and a number (age of a person) on the other. You are told the following rule:

If a person drinks beer, (s)he has to be over 21 years old.

-------- -------- -------- ---------
| | | | | | | |
| Beer | | Cola | | 23 | | 16 |
| | | | | | | |
-------- -------- -------- ---------

Now, which of the cards would you turn over to check whether the rule is correct?

Most people find this task much easier than the original Wason Selection Task. (The answer is, of course, to turn over the cards with Beer and 16). The tasks are essentially the same, but real-world thinking simplifies the reasoning enormously.