One modernist argument for applying ijtihad to sharia law is that while "the principles and values underlying Sharia (i.e. "usul al-fiqh")" are unalterable, human interpretation of sharia is not. Another, (made by Asghar Ali Engineer of India), is that the "adaat" (customs and traditions) of Arabs were used in the development of the sharia, and form an important part of it. They are very much not divine or immutable, and have no more legal justification to be part of the sharia than the "adaat" of Muslims living beyond the home of the original Muslim in the Arab Hejaz. The