Refers to the often-experienced situation of frustration and lack of progress/advancement caused by the infamous "double-face" that so many lazy/selfish/insensitive people rapidly vacillate between, depending on current conditions --- one moment they may be robustly cheerful and agreeably open-minded, and then if someone mentions an unwelcome subject or task, they suddenly "morph" into an irritable depressed "limp rag" who does not wish to bestir himself or cooperate/assist in any way.
Morphy's Law: The level of energy/patience/good humor that someone possesses is in direct inverse proportion to the desirability of the topic under discussion, the amount of strenuous labor involved in a proposed task, etc.
by QuacksO January 4, 2017