“…Among the earlier ideas are Luchins' concept of einstellung (blind spot) and Duncker's functional fixedness, as in Maher (1992). More recently, there have been two developed theoretical ideas: (1) Criterion for Satisfactory Progress theory (Chu, Dewald, & Chronicle, 2007;MacGregor, Ormerod, & Chronicle, 2001), and (2) Representational Change Theory (Knoblich, Ohlsson, Haider, & Rhenius, 1999). We will discuss these theories in more detail in Section 4.…”