This research deals with a comprehensive and multifaceted analysis of the concept of "Istahālah" as one of the purported terms in Imami jurisprudence. The present research, adopting a descriptive-analytical approach, first examines the historical evolution of this rule from the words of early jurists to the detailed analyses of later jurists, especially the turning point created by Sheikh Ansari. Accordingly, it is clear that the main dispute of jurists was not over the principle of purported purport of Istahālah, but over the recognition of instances and realization of "true change of subject". In the following, the jurisprudential foundations of the rule, based on the rational-customary principle of "the disappearance of the subject of the ruling with the disappearance of its subject" (intifā al-hikam bantifā mahsouh), and the main criterion for its recognition, namely "change of name from the perspective of custom", are explained. This article also deals with the relativization of transformation with the similar concept of “revolution” and explores the three approaches of synonymy, contrast, and distinction based on reason. The final part of the research, by entering the interdisciplinary field, discusses the challenge of adapting the “conventional” criterion to the achievements of the “empirical sciences” and shows how precise chemical tools can be a guide for jurisprudence in detecting the essential changes of substances and determining instances of transformation, especially in complex and industrial cases. Finally, this research emphasizes the necessity of a constructive dialogue between jurisprudence and modern sciences to achieve more precise criteria in detecting transformation.