Al-Ghazali's Debt and the Work's Lasting Influence

Al-Burhan's most immediate and profound influence was on al-Ghazali, who absorbed its arguments during his years of study under al-Juwayni and then developed them further in his own Al-Mustasfa min Ilm al-Usul, generally regarded as the greatest single work in classical usul al-fiqh. The relationship between Al-Burhan and Al-Mustasfa is one of the most instructive in the history of Islamic thought: al-Ghazali took the framework al-Juwayni had built, refined its philosophical apparatus using his own deeper engagement with Aristotelian logic, and produced a more systematic and more accessible work. Without Al-Burhan, Al-Mustasfa would not exist in the form it does.

Beyond al-Ghazali, al-Juwayni's influence on the development of Ash'ari-Shafi'i usul al-fiqh is pervasive. The theory of the purposes of the law (maqasid), which al-Juwayni sketched in Al-Burhan, was developed by al-Ghazali, al-Amidi, al-Qarafi, and ultimately by Ibn Ashur into one of the most important frameworks in Islamic legal theory. The epistemological framework al-Juwayni developed — the careful analysis of certainty and probability, the conditions for rational inference, the status of linguistic evidence — set the terms for subsequent discussion in the field.

Al-Amidi's Al-Ihkam, which is in many respects the culmination of the Shafi'i-Ash'ari usul al-fiqh tradition, acknowledges al-Juwayni as a major authority and frequently engages with his positions. The line of development from al-Juwayni through al-Ghazali to al-Amidi represents the mature flowering of a tradition of legal philosophy that al-Juwayni was central in shaping.

Modern Western scholarship on Islamic legal theory has recognized al-Juwayni as a crucial figure. Wael Hallaq's studies of Islamic legal theory place Al-Burhan at a pivotal moment in the tradition's development. The first critical edition, produced by Abd al-Azim al-Dib in two volumes, made the text more accessible and generated renewed scholarly interest. Al-Dib also produced a valuable study of al-Juwayni's legal thought that situates Al-Burhan in its intellectual context.