It was an appealing and apparently convincing message.
Indeed, the concept enjoyed such strong popularity and intuitive appeal that no one bothered to check the facts.
The correct solution, however, requires you to draw lines that extend beyond the area defined by the dots.
At the first stages, all the participants in Guilford’s original study censored their own thinking by limiting the possible solutions to those within the imaginary square (even those who eventually solved the puzzle).
It's an interesting experiment, but the author's conclusion cannot possibly follow from the results of it.
Would you like to guess the percentage of the participants in the second group who solved the puzzle correctly?No one, that is, before two different research teams—Clarke Burnham with Kenneth Davis, and Joseph Alba with Robert Weisberg—ran another experiment using the same puzzle but a different research procedure.Both teams followed the same protocol of dividing participants into two groups.He challenged research subjects to connect all nine dots using just four straight lines without lifting their pencils from the page.Today many people are familiar with this puzzle and its solution.