 Galen proposed that when the soul is moved by too much enjoyment, it reaches states of "incontinence" and "licentiousness", the inability to willfully cease enjoyment, which was a negative consequence of too much pleasure.In order to unite his theories about the soul and how it operated within the body, he adapted the theory of the pneuma, which he used to explain how the soul operated within its assigned organs, and how those organs, in turn, interacted together.Galen then distinguished the vital pneuma, in the arterial system, from the psychic pneuma, in the brain and nervous system.