Editing Problem solving (section)

===Unnecessary constraints===
Unnecessary constraints are arbitrary boundaries imposed unconsciously on the task at hand, which foreclose a productive avenue of solution. The solver may become fixated on only one type of solution, as if it were an inevitable requirement of the problem. Typically, this combines with mental set—clinging to a previously successful method.<ref name="Kellogg, R. T. 2003">{{cite book|last=Kellogg|first=R. T.|year=2003|title=Cognitive psychology|edition=2nd|location=California|publisher=Sage Publications, Inc.}}</ref>{{page needed|date=September 2023}}

Visual problems can also produce mentally invented constraints.<ref>{{cite book|last=Meloy|first=J. R.|year=1998|title=The Psychology of Stalking, Clinical and Forensic Perspectives|edition=2nd|location=London, England|publisher=Academic Press}}</ref>{{page needed|date=September 2023}} A famous example is the dot problem: nine dots arranged in a three-by-three grid pattern must be connected by drawing four straight line segments, without lifting pen from paper or backtracking along a line. The subject typically assumes the pen must stay within the outer square of dots, but the solution requires lines continuing beyond this frame, and researchers have found a 0% solution rate within a brief allotted time.<ref>{{cite journal|last2=Ormerod|first2=T.C.|last3=Chronicle|first3=E.P.|year=2001|title=Information-processing and insight: A process model of performance on the nine-dot and related problems|journal=Journal of Experimental Psychology: Learning, Memory, and Cognition|volume=27|issue=1|pages=176–201|doi=10.1037/0278-7393.27.1.176|last1=MacGregor|first1=J.N.|pmid=11204097}}</ref>

This problem has produced the expression "[[think outside the box]]".<ref name="Weiten, Wayne 2011">{{cite book|last=Weiten|first=Wayne|year=2011|title=Psychology: themes and variations|edition=8th|location=California|publisher=Wadsworth}}</ref>{{page needed|date=September 2023}} Such problems are typically solved via a sudden insight which leaps over the mental barriers, often after long toil against them.<ref>{{cite book|last1=Novick|first1=L. R.|last2=Bassok|first2=M.|year=2005|chapter=Problem solving|editor-first1=K. J.|editor-last1=Holyoak|editor-first2=R. G.|editor-last2=Morrison|title=Cambridge handbook of thinking and reasoning|pages=321–349|location=New York, N.Y.|publisher=Cambridge University Press}}</ref> This can be difficult depending on how the subject has structured the problem in their mind, how they draw on past experiences, and how well they juggle this information in their working memory. In the example, envisioning the dots connected outside the framing square requires visualizing an unconventional arrangement, which is a strain on working memory.<ref name="Weiten, Wayne 2011" />