"On the Anatomy of Nerves": A treatise dealing with the analytical presentation of the 7 pairs of cerebral nerves and the brief presentation of the pairs of spinal nerves. "On the Organ of Smell": A treatise aiming to prove exactly what part and what mechanism achieves the sensation of smell.
"On the Anatomy of the Uterus": A concise description of the uterus and an introduction to embryology, with emphasis on the anatomical formations that connect the embryo to the uterus.
"That the Powers of the Body Follow the Powers of the Soul": In this work, Galen supports the holistic view, pioneering for his time, that the actions of the soul are influenced by the conditions of the body.
"On the Diagnosis and Treatment of the Specific Affections of the Soul": The definition and distinction of passion and error. The relationship between passions and errors. A catalog of the soul's passions. The recommended approach for diagnosing and uprooting passions from the human soul. Autobiographical information and examples from everyday life that strengthen the argumentation.
"On the Diagnosis and Treatment of the Sins of the Soul": The errors of judgment and the method of avoiding them, similar to the method of avoiding the passions of the soul. Passion as the cause of errors in judgment.