[source: Islam and Democracy, p. 

IBN TAYMIYYAH SAID INITIAL CALIPHS RULED FROM CONTRACT WITH THE COMMUNITY THEY GOVERNED (CONSENT)
Ibn Taymiyyah...After the fall of the Abbasid caliphate, he argued that the caliphs after the 
first four successors to the Prophet were temporal rulers whose "authority as imams is acquired 
by a mutual contract with the Community in general, whereby the temporal princes, in close 
collaboration with the ulama, carry out their religious and political functions as the sharia 
directs and receive in return loyal obedience from the people." 
[source: Islam and Democracy, p. 48]