This research focuses on the previously unpublished treatise by Sayyid Sharīf al-Jurjānī, Risāla fī taqsīm al-‘ilm. The research is based on comparative evaluation of available manuscipts and is composed of a critical edition of the treatise and its analysis. The treatise is about the division (taqsīm) of tasawwur (conception) and ta~dīq (assent) as divisions of knowledge. Al-Jurjānī presents views from different schools of logic. In the analysis section, I discuss the treatise’s philosophical background and show that the aforementioned division is the first step of a chain of propositions on what the goal and methods of logic are focusing on the possibility of learning. Remaining sections focus on the references in the treatise to various views and summarise them. Finally al-Jurjānī’s position in this scene is made explicit through his critical analysis of competing views advocated by these different schools. For al-Jurjānī, division of knowledge can be analysed formally and informally. Formally, the division should be restrictive and informally, it should emphasize methods of logic, that are proof (hujja) and definition (ta‘rīf). The article shows that the goal of al-Jurjānī’s discussion on the division of knowledge as conception and assent is basically to take the discussion out the context of traditional discussions on quiddity but rather build it on the division formally and the goals of the division informally.