A Survey of the Arguments for the Mobility of the Earth in Qānūn Nāṣirī

The arguments for the mobility (orbital and spin) of the Earth and the solutions for the natural and observational criticisms have been one of the major problems in the acceptance or rejection of the heliocentrism. Although the works of the Islamic scholars in medieval period have dedicated to find observational reasons for the immobility of the Earth, it seems in the literature of the Qajar period, the observational arguments are less important than natural arguments.ʿAbd al-Ghaffār Najm al-Dawla elaborates on the issues of modern astronomy and astronomical discoveries in his book Qānūn Nāṣirī (1867). Although the topics inside this book do not go beyond the level of popular science publications, a study of its content is necessary to understand the astronomical arguments raised for the mobility of the Earth during the Qajar period. This article reviews the reasons which Najm al-Dawla presented for the mobility of the Earth in his Qānūn Nāṣirī.