Galen went to great lengths to refute a view that was apparently circulating in his time (but whose originators or protagonists he did not mention) according to which the pineal gland regulates the flow of psychic pneuma in the canal between the middle and posterior ventricles of the brain, just as the pylorus regulates the passage of food from the esophagus to the stomach. Galen rejected this view because, first, the pineal gland is attached to the outside of the brain and, second, it cannot move on its own. He argued that the “worm-like appendage” [epiphysis or apophysis] of the cerebellum (nowadays known as the vermis superior cerebelli) is much better qualified to play this role (Kühn 1822, pp. 674–683; May 1968, vol. 1, pp. 418–423).