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.Let’s look a little more closely at these surprising results.Solving this problem requires people to literally think outside the box.Although studying creativity is considered a legitimate scientific discipline nowadays, it is still a very young one. One of Guilford’s most famous studies was the nine-dot puzzle. Guilford was one of the first academic researchers who dared to conduct a study of creativity.The symmetry, the beautiful simplicity of the solution, and the fact that 80 percent of the participants were effectively blinded by the boundaries of the square led Guilford and the readers of his books to leap to the sweeping conclusion that creativity requires you to go outside the box.

That is, direct and explicit instructions to think outside the box did not help.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.your conclusion: that the second experiment disproves the theory that thinking outside the box is useful in solving problems, is itself a fallacy.

That is, direct and explicit instructions to think outside the box did not help.

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.

your conclusion: that the second experiment disproves the theory that thinking outside the box is useful in solving problems, is itself a fallacy.

Because the solution is, in hindsight, deceptively simple, clients tended to admit they should have thought of it themselves.