[Galen " On the anatomy of nerves": Translation from the Greek text and discussion].
Galen's treatise "On the Anatomy of Nerves" was translated literally from the Greek text (Kuhn's edition, vol. 2, pp. 831-856) into Japanese, utilizing the knowledge of anatomy. The previous Latin and English translations, as well as the descriptions of the nervous system in the other Galenic texts such as "Anatomical Procedures" and "On the Usefulness of the Parts of the Body," were utilized as references for the present translation, but it became evident from the present study that the previous translations contained an abundance of immature and erroneous understandings of the Galenic text. The present study has made it clear that the third cranial nerve referred to by Galen contains the most branches of the trigeminal nerve, and that the fourth cranial nerve represents the sympathetic trunk and the palatine nerves. The Galenic texts which were translated into Latin mainly in the 16th century before development of anatomical knowledge contain misunderstandings peculiar to the age. Thus the modern translations inherit some misunderstandings found in those Latin translations. Descriptions in the Galenic "On the Anatomy of Nerves" appear vague at first sight, but the described structures can be identified in most cases without doubt on the basic of anatomical knowledge. Furthermore we can estimate how Galen developed the preceding understanding of the nervous system made by Marinus on the basis of his own observations.