The nine-dot problem: Beyond perceptual organization


A dozen versions of the nine-dot problem were individually administered. Instructions stating that S could extend his lines beyond the boundary of the square formed by the nine dots were marginally effective in increasing the number of Ss who solved the problem in a 10-min period. Presenting two extra dots outside the square dramatically increased the number of solvers. It was concluded that perceptual organization, seeing the dots as a confining square, is a minor factor in making the problem a difficult one. The source of the difficulty is, instead, the fact that the sequence of lines involved in the solution is nonobvious.


  1. KENDLER, H. H. Basic psychology. (2nd ed.) New York: Appleton-Century-Crofts, 1968.

    Google Scholar 

  2. KRECH, D., CRUTCHFIELD, R. S., & LIVSON, N. Elements of psychology. New York: Knopf, 1969.

    Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Clarke A. Burnham.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Burnham, C.A., Davis, K.G. The nine-dot problem: Beyond perceptual organization. Psychon Sci 17, 321–323 (1969).

Download citation


  • Test Item
  • Perceptual Organization
  • Direct Solution
  • College Freshman
  • Habit Strength