y ▁of ▁D hu ▁Mar mar . ▁Al - H us ay n ▁briefly ▁moved ▁the ▁headquarters ▁of ▁the ▁T ay y ib i ▁da ʿ wa ▁to ▁D hu ▁Mar mar , ▁before ▁returning ▁to ▁S ana ' a . ▁ ▁He ▁was ▁also ▁the ▁author ▁of ▁a ▁number ▁of ▁treat ises ▁on ▁T ay y ib i ▁es oter ic ▁doctrine ▁( ḥ a q ā ʾ i q ), ▁not ably ▁the ▁al - M ab da ʾ ▁wa ' l - ma ʿ ā d , ▁which ▁de als ▁with ▁T ay y ib i ▁conception s ▁of ▁cosm og ony ▁and ▁es chat ology . ▁ ▁He ▁was ▁succeeded ▁by ▁his ▁son ▁Ali , ▁who ▁had ▁been ▁his ▁father ' s ▁chief ▁assistant . ▁ ▁Works ▁An ▁ 1 8 th - century ▁catalog ue ▁of ▁Is ma ' ili ▁literature ▁attributes ▁several ▁works ▁on ▁T ay y ib i ▁es oter ic ▁the ology ▁( ḥ a q ā ʾ i q ) ▁to ▁him , ▁held ▁by ▁the ▁Bo hr as ▁in ▁India . ▁Most ▁of ▁them ▁are ▁un pub lished , ▁held ▁in ▁ 1 9 th - ▁or ▁ 2 0 th - century ▁copies ▁by ▁the ▁Institute ▁of ▁Is mail i ▁Studies ▁of ▁London . ▁ ▁His ▁Ris ā lat ▁al - m ab da ʾ ▁wa ' l - ma ʿ ā d ▁(" T re at ise ▁on ▁the ▁origin ▁and ▁return "), ▁a ▁brief ▁but ▁conc ise ▁ex position ▁of