Page "Emperor Ruizong of Tang" Paragraph 29

Later in 712, Princess Taiping had astrologers warn Emperor Ruizong that the constellation that symbolized the imperial throne, Dizuo ( 帝座 ), showed that there would be a change in the emperor's position — believing that Emperor Ruizong would suspect Li Longji of plotting a coup and that she could remove Li Longji this way.

Instead, Emperor Ruizong, reasoning that the change in the emperor's position could be accounted by an orderly transition, offered to pass the throne to Li Longji.

Princess Taiping fervently opposed it, and Li Longji initially declined, but at Emperor Ruizong's insistence finally accepted and took the throne ( as Emperor Xuanzong ).

However, at Princess Taiping's suggestion, Emperor Ruizong retained much of the imperial power as Taishang Huang ( retired emperor ), and his edicts continued to carry greater force than Emperor Xuanzong's.