The concept of Imam Ali (peace be upon him) being the "Straight Path" is a spiritual and mystical subtlety that has been significantly addressed in narrations. However, Mulla Sadra's explanations on this matter are novel and are considered among his philosophical innovations. According to Mulla Sadra, the Straight Path—Amir al-Mu'minin (peace be upon him)—is the form, identity, and true reality of humanity as it is possible and fitting to be. The Straight Path is the truth, form, and identity of the perfect human, which has manifested in the noble aspect of Amir al-Mu'minin (peace be upon him) in the natural world, before nature, and after nature. The manifestation of the Path in the creatural and ethical aspect of Amir al-Mu'minin (peace be upon him) is the most complete exemplar of the Path. Everyone shares in humanity to the extent of their resemblance and affinity with the perfect human and the guardian of God—the Almighty—and Amir al-Mu'minin (peace be upon him). Conversely, to the extent of their aversion, disparity, and opposition to the perfect human and Amir al-Mu'minin (peace be upon him), they are deprived of human aspect and perfections, and indeed, of human existence. This research, employing an analytical-descriptive method and by exploring the works of Mulla Sadra and analyzing his philosophical views, has arrived at the aforementioned conclusion.