There are six glasses in a row. The first three are full of water, and the next three are empty. By moving only one glass how can you make them alternate between full and empty?
Four cards are placed in front of you on the table, each with a number on one side and a color on the other. The visible cards show 3, 8, red and brown. Which cards should you turn over in order to test the truth of the statement that if a card shows an even number on one face, then its opposite face is red?
You’d need to turn over only the 8 and brown card. Only a card with an even number on one face and which is not red on the other face can invalidate the stated rule. If you turn over the 3 card and it’s not red, it doesn’t invalidate the rule, nor does turning over the red card and finding it has the label 3.
This test was devised by Peter Cathcart Wason and is known as the Wason selection task. Less than 10% of test subjects got it correct in two separate studies.
Zero. The Nile is the longest river in the world. Some claim the Amazon as the longest, but that too has no “S”es (that looks weird but I don’t know how else to write the plural of “s”). The Mississippi is the 4th largest river in the world according to a href=”https://en.wikipedia.org/wiki/List_of_rivers_by_length”>Wikipedia.
Chuck and Ruby were going to meet at a hotel for their anniversary dinner, but Ruby didn’t show. Chuck was angry and left her a passive aggressive message on their kitchen table in the form of fifteen matchsticks spelling “hotel” and went to bed. When Ruby got home and saw the matchsticks, she removed one and went to bed. When Chuck woke up the next morning and saw Ruby’s new message, he realized his mistake. Which stick did Ruby remove and what was the new message?
Ruby had removed the top of the T and the new message could be seen upside down from where Chuck sat at his breakfast of sadness and anger. What he saw was 7 3 1 0 4, or 7/31/04, the date of their anniversary. In his excitement, Chuck had gone to the restaurant a day early, on July 30th. All was forgiven by both parties and Chuck and Ruby had a wonderful dinner together. They also promised to buy a whiteboard for the kitchen so they wouldn’t have to use matchstick messages ever again.