Islamic tradition ... sustains the unified character of society while elaborating its exoteric and esoteric dimensions. The exoteric dimension concerns Divine Law (Shari'ah) and man's behaviour, but it is not directly related to the creative principles of the traditional man. Rather it is the gnostic aspect of Islam, the Way, (Tariqah), in which are found the principles which govern Islamic Art.
From Ardelan & Bakhtiar, The Sense of Unity. p.3