Cause  Effect
Linear = one direction (no feedback loops)
Demonic Possession (Medieval Europe)
Somatogenic Models (late 19th-early 20th c.)
General paresis caused by spirochete Treponema pallidum (discovered by Noguchi & Moore in 1913)
Psychogenic Models (late 19th-early 20th c.)
Psychoanalysis: Conversion & neurotic conditions caused by inner-drive conflicts (Freud)

Tomàs, J.