Ellis, here is the thread on 'pneumatology'
Pneumatology--study of the spirit, of spiritual beings and phenomena, especially the interactions between humans and God. Pneuma (πνευμα) is Greek for "breath", which metaphorically describes a non-material being or influence. World Book Dictionary defines pneumatology as "1. Theology the doctrine of the Holy Spirit. 2. The doctrine of spirits or spiritual beings, in the 1600s considered a branch of metaphysics. 3. pneumatics. 4. Obsolete word for psychology."
In Christian theology pneumatology refers to the study of the Holy Spirit. In mainstream Christian doctrine, the Holy Spirit is the third person of God in the Trinity. Unitarian forms of Christianity believe that the Holy Spirit is personal, although holding that it may, in some sense, influence people. In the Gospel of John, pneuma is linked to re-birth in water and spirit, which has been suggested to be baptism.
The pneumatology of Philo
Philo (20 B.C. - 40 A.D.) was an Alexandrian Jewish philosopher known for his study of pneumatology. He treats God's divine powers by treating them as a single independent being, which he designates "Logos". This name, which he borrowed from Greek philosophy, was first used by Heraclitus and then adopted by the Stoics.
World Book Dictionary points out that it is an archaic term for psychology.
