A link to a talk on Islamic spirituality and Sufism by professor Sayyed Hosain Nasr of George Washington University. He is regarded as an authority on Islam and Sufism. His under graduate degree is in physics and mathematics from MIT. Masters from Harvard in earth sciences and a PhD in history of science and philosophy also from Harvard in 1958. He has published about 50 books and several hundred articles.
A link to an explanation of “what is spirituality (about 5 minutes) by professor Sayyed Hasan Nasar of George Washington University who is regarded as an authority on Sufism and Islam.