The science of jurisprudence is the knowledge of the lawful and unlawful rulings, and the science of jurisprudence is not known except by knowing the evidence of the rulings, and knowledge of this evidence is only after knowing the science of the principles of jurisprudence; thus, the science of the principles of jurisprudence is the collection of all good. The rules of the principles of jurisprudence are very important, so whoever wants to master any science must memorize the rules that pertain to it, because whoever memorizes the principles of jurisprudence, masters them, and controls them, it will be easy for him to return every subsidiary issue that comes to him to its origin, and among these rules is the rule (the means have the rulings of the ends In this research, I have explained this rule according to Imam Al-Kasani and its importance to man in terms of rulings, whether they are acts of worship or transactions, and the role of this rule in man’s life.
Dawood Ahmed (Mon,) studied this question.