# 49. Manipulation of bias and heuristics in decision making ## 49.5. Methodology/Refinements/Sub-species ### 49.5.24. Functional fixedness This is the acceptance of functional limits placed on the use of an object only in the way it is traditionally used. A manipulator forces the victim back into a "functional box" by reiterating that a door of a burning house can only be opened with a key whilst ignoring the sledge hammer, crow bar or mechanised digger standing nearby.