This paper introduces the term “Open Constitution” as a crucial element for fostering an “Open Society.” It explores the nature and adaptability of constitutions, emphasizing the balance between stability and the necessity for change. Specifically, it examines Iran’s 1906 and 1979 constitutions, highlighting their initial lack of clear amendment procedures and the subsequent modifications aimed at addressing this issue. The 1906 Constitution did not establish a clear amendment process, which was only partially rectified in 1949. Similarly, the 1979 Constitution remained silent on amendments until Article 177 was added during its 1989 revision, outlining a heavily controlled revision process. Both constitutions contain principles deemed unchangeable; however, historical precedents indicate that such provisions are not immune to alteration. The paper concludes that the rigidity of these constitutions, coupled with the absence of practical mechanisms for public or specialized input, poses a risk to political stability and may lead to revolutionary changes. It argues that these constitutions, due to their stringent emphasis on stability and resistance to public demands for change, are inherently self-destructive.