Muslim heresiographers present the medieval rationalist school of theology known as the Mu‛tazila as heretics, while modern Western and modernist Muslim scholarship almost invariably present the Mu‛tazila as the original free-thinkers of Islam. The result is a polarized view of the Mu‛tazili tradition; Islamists view the Mu‛tazila as a heresy best forgotten while modernists, Muslim and Western, as historical proof of Islam’s essentially rational character. The present study is an attempt to problematize both perspectives by reexamining the concepts of reason (or rationalism) and tradition (or traditionalism) in light of Mu‛tazilite theology and ethics. This analysis shows that the modern heirs of Mu‛tazili thought are not be sought in Muslim scholastic theology or Enlightenment liberalism, but in the postmodern critiques of Western Muslim scholars such as Tariq Ramadan and Khaled Abou El Fadl.