Ja'far ibn Muhammad al-Sadiq (The Truthful)

Great-grandson of Ali ibn Abi Talib and Fatimah al-Zahra, Ja'far al-Sadiq navigated the collapse of the Umayyads and the rise of the Abbasids by strictly eschewing political revolts, dedicating his life entirely to intellectual, ethical, and spiritual enlightenment.

His school in Medina drew thousands of scholars, including Abu Hanifa (who famously declared: "Were it not for the two years I spent with Ja'far, I would have perished") and the father of chemistry Jabir ibn Hayyan (Geber). He expounded the theological doctrine of "the position between two extremes" (Amr bayn al-Amrayn).