 Having studied Islamic Law, he argued that "it was necessary to adapt the Sharia to new circumstances" and that there was not much difference between "the principles of Islamic law and those principles of 'natural law' on which the codes of modern Europe were based".Like Tahtawi, Khayr al-Din was also sent to Paris where he spent four years.After his return from Europe he wrote a book in which he argued that the only way to strengthen the Muslim States was by borrowing ideas and institutions from Europe, and that this did not contradict the spirit of the Sharia.