The great Psychiatrist Carl Jung (1875-1961) founded Analytical Psychology.  He believed you could learn a lot about the psyche by studying peoples dreams, art, philosophy and religion.  Jung emphasized the idea of balance in life.  His most notable contributions include his concept of the psychological archetype, the collective unconscious, and his theory of synchronicity (a favorite subject of mine that I've blogged about before).  Jung studied the symbolism of complex mystical traditions such as Gnosticism, Alchemy, Kabala, and similar traditions and his theories regarding archetypes was based on those readings.
Jung was known to have prophetic dreams.  In 1913 he dreamed of a flood engulfing most of Europe.  At the end of the dream, the water turned to blood.  A few weeks later, he dreamed of severe winters and , again, rivers of blood.  He thought he was going psychotic.  A few months later, World War I started and Jung realized the dream had come true. 
After that, he spent much of his time, until 1928, in a process of self-exploration.
While Freud divided the mind into the concious and subconcious, Jung divided it into three:
The ID or concious where all of out concious mental activities occur,
The Personal Unconcious where our hidden thoughts, desires, fears, etc that can become concious are,
The Collective Unconcious, a reservoir of our experiences as a species occupied by archetypes; an unlearned tendency to experience things in a certain way.