 But the most rewarding medical text for philosophical readers is Doubts about Galen. Or rather, it should be said that this work deals with a range of philosophical, as well as medical, issues, including the relation between soul and body, vision, atomism, and pleasure (see the ample introduction by Koetschet in al-Rāzī, DG). Regarding the first of these issues, al-Rāzī criticizes Galen for suggesting that the soul is entirely dependent on bodily states or “temperament”, that is, the mixture of the body’s constituents. As in the Spiritual Medicine, he defends Plato’s idea that the rational part of the soul only uses the brain as an “instrument (āla)”, and that injury to the brain impedes rational function only in the way that damage to a flute would make it harder for the flute player to perform (al-Rāzī, DG: §21.4). When it comes to vision, al-Rāzī strikes a less Platonist note, since he rejects Galen’s “extramissionist” theory, which is in part inspired by Plato’s Timaeus. According to Galen, spirit (pneuma) is sent forth from the eyes and transforms air, making it into an instrument for contacting the visual object (Ierodiakonou 2014). Instead, al-Rāzī defends the view that incorporeal images are sent from the seen object and arrive at the eye (Koetschet 2017a).