Two centuries ago, if a Westerner, or for that matter a Chinese Confucian or a Hindu from India, were to study Islam, he would have encountered but a single Islamic tradition.
Such a person could have detected numerous schools of thought, juridical and theological interpretations and even sects which remained separated from the main body of the community. He would moreover have encountered both orthodoxy and heterodoxy in belief as well as in practice. But all that he could have observed, from the esoteric utterances of a Sufi saint to the juridical injunctions of an ?dim, from the strict theological views of a Hanbalite doctor from Damascus to the unbalanced assertions of some extreme form of Shi’ism, would have belonged in one degree or another to the Islamic tradition: that is, to that single tree of Divine Origin whose roots are the Quran and the Hadith, and whose trunk and branches constitute that body of tradition... that has grown from those roots over some fourteen centuries in nearly every inhabited quarter of the globe".
To read further, Traditional Islam in the Modern World - Seyyed Nasr
