Device to stop, hinder, or trick; pl. hiyal. Stratagem to avoid or circumvent legal principles or rigid constructs. A book on hiyal attributed to Muhammad al-Shaybani led to the belief that the Hanafi school was the first to champion the use of hiyal. Initially other schools of thought condemned the practice, but later their fuqaha utilized hiyal to solve contradictions between the dictates of executive powers or cultural choices and Quranic principles.