 This is one of only two complete surviving works by al-Rāzī devoted solely to a philosophical topic; the other one also deals with ethics. This is The Spiritual Medicine (Arabic edition in al-Rāzī RF; English translation in al-Rāzī  SPR  and for discussion Adamson 2016), a longer book of ethical advice presented to his patron al-Manṣūr as a complement to the aforementioned medical treatise. Here al-Rāzī offers treatment for the soul, following on his overview of treatments for the body (Adamson 2019). Apart from this, the most significant surviving work for his philosophy is his Doubts about Galen (Arabic critical edition and translation by Koetschet in al-Rāzī  DG).  Al-Rāzī considered Galen the greatest of medical authorities, but on the basis of Galen’s own critical attitude towards esteemed predecessors, felt free to critique weak points in the extensive corpus of Galenic works that had been translated into Arabic. While a number of these points naturally concern medicine, the Doubts also touches on a wide range of philosophical issues, as discussed below.