Fadl deliberately ignored the 1400 year vicious schism between the two great Islamic denominations, Sunni and Shia in his analysis. Is this an error as Muslims fighting Muslims worsens?  He focused instead on the extremism typology between the "puritans and the moderates" or literal versus figurative interpretations advanced by both.  "It is important to note that the two orientations described in this book cut through the Sunni and Shi’I sectarian divide."  The  rift in demonominations  is older and deeper  than the tensions between Protestants and Catholics, which bedeviled Europe for centuries.  Courageous leaders in Europe gave their lives for a renaissance of more enlightened religious thinking.  Islam needs the same  renaissance away from the invidious fundamentalist extremism of ISIS.  Fadl wisely says Muslims fear  of  fitna (sedition and divisiveness), a grievous sin is creating  the risk of losing  "the very  soul of Islam" from apathetic indifference.  (page 15).