Uthman ibn Affan and Ali ibn Abi Talib also were called by the same title , while the Shi'a consider Ali to have been the first truly legitimate caliph .
They concede that caliph accepted caliph 's 's 's predecessors .
Uthman ibn Affan and Ali ibn Abi Talib also were called by the same title , while the Shi'a consider Ali to have been the first truly legitimate caliph , although they concede that Ali accepted his predecessors .