during or after the Ming dynasty. However, there are artefacts dating from earlier than the Ming dynasty, such as the plaques on the gates of the second courtyard, which were plaque carvings dated from the Song dynasty (see image above). Each courtyard contains a central monument, such as a gate, and is lined with greenery as well as subsidiary buildings. Paifangs () frame all the courtyards. They are imperially commissioned arches that commemorate those that have contributed to the state. Some scholars claim that the number of paifangs in the courtyard implies that the Muslim Hui community were treated as equal citizens, in the same way as Han citizens. The first courtyard, for instance, contains a Qing dynasty monumental gate, while the fourth courtyard houses the Phoenix Pavilion, a hexagonal gazebo. Walls throughout the complex are carved with plant and object motifs, and inscriptions in both Chinese and Arabic. Stone steles record repairs done to the mosque and feature calligraphic works. In the second courtyard, two steles display texts that promote ethnic harmony (for instance, as attached in the figure above, one of the steles draws upon prominent connections between the Islamic faith and Taoism), one of them supposedly featuring scripts of the calligrapher Mi Fu of the Song dynasty. The Shengxinlou (), or “Examining the Heart Tower,” is a three-story, octagonal pagoda in the third courtyard. The structure contains a number of steles dating to as early as the Tang dynasty. The presence of these, often large, steles have been used to support the Tang establishment of the mosque. Despite the usage of this complex as a mosque, the Great Mosque of Xi'an is notable for lacking a minaret. However, some scholars, such as Dr. Nancy Steinhardt from the University of Pennsylvania, speculate that the Xingxin Tower originally served as the mosque's minaret that was previously used for the call to prayer. This courtyard is for visitors to attend prayer services. Today the third courtyard is where many of the mosque community's daily activities take place. For instance, the mosque's central kitchen, the residential Imam's office, and other governmental administrative departments are located here. The fourth courtyard has a bigger prayer hall that can seat more than a thousand people. Prayer hall It is believed that the prayer hall was constructed during the Ming dynasty, although significant reconstructions occurred during the Qing era. This argument has been supported by