Here's something for the starving minds. I came across Wason Selection Task while reading an article Test (wiki citation): You are shown a set of four cards placed on a table, each of which has a number on one side and a colored patch on the other side. The visible faces of the cards show 3, 8, red and brown. Which card(s) must you turn over in order to test the truth of the proposition that if a card shows an even number on one face, then its opposite face is red? Refer: Wason Selection Task See also: Scientific American - similar challenges
