Carl Jung newly released secret diary starts off with this quote:

The years of which I have spoken to you, when I was pursued by inner images, were the most important time of my life.  Everything else is to be derived from this.  It began at that time, and the later details hardly matter anymore.  My entire life consisted in elaborating what had burst forth from the unconscious and flooded me like an enigmatic stream and threatened to break me.  That was the stuff and material for more than only one life.  Everything later was merely the outer classification, the scientific elaboration, and the integration into life.  But the numinous beginning, which contained everything, was then.

Carl Jung was a deeply flawed man in many regards, he professed racist views in public lectures, and he carried on extra-marital affairs most of his adult life.  Carl Jung was also a genius who revolutionized psychology, and created a form of therapy called Analytical Psychology.  He was a profoundly sensitive man who used that sensitivity to explore his own inner world, but he was also a doctor, and as the above quote implies – he at least partially explained his own mysterious experience by writing.

As a young man Jung had several mystical experiences – by mystical I mean first-hand inexplicable experiences of something out of the ordinary that defies rational explanation.  Including a cousin who could act as a medium at seances and apparently channel spirits.  Jung started his career with a disposition to believe in the super-natural world, and used his ideas in treatment of schizophrenics.  However, he didn’t publicly reveal this side of himself till he was more established later in life.

Jung began his medical career working in a progressive mental hospital, the Burgholzi.  Sigmund Freud was becoming a major public figure, and according to Jung – not highly esteemed at first in the medical community.  However Jung saw potential in what Freud wrote about, especially about interpreting dreams.  The mistake id often made that Jung’s theories are purely an off shoot of Freud’s, this is what Jung said regarding that:

I in no way exclusively stem from Freud.  I had my scientific attitude and the theory of complexes before I met Freud.  The teachers that influenced me above all are Bleuler, Pierre Janet, and Theodore Flournoy.

Jung however clearly was influenced and was an early disciple of Sigmund Freud, and in some ways Jung theories are based on the work Freud did.  Jung differed in one major way from Freud:  Freud considered the base of mankind’s behavior to be drives, and Jung considered it to be the unconscious.  For Freud the drives could be treated scientifically, and they also explained most of Human behavior and neurosis.  Jung presents a different, more romantic view of Human nature by insisting that the base layer of human existence is unknowable – hence the unconscious.

The schism between Freud’s drives and Jung’s mysteries is what has motivated opposing schools of brilliant people throughout the 20th, and now into the 21st century.

I prefer Jung’s method, because I do better emotionally when I allow myself to believe there is some mystery to life.  That I can’t know some stuff.  Freud’s viewpoint is very close to reducing humanity to animals, and while that may technically be correct – it just doesn’t do it for me.  You should explore both, and see what makes sense for you.

Freud and Jung went back and forth over their disagreements.  In this letter Freud concedes that Jung has made some good points about the unconscious and supernatural side of experience:

Vienna IX, Bergasse 19

June 15, 1911

Dear Friend, …In matters regarding occultism I have become humble ever since the great lesson I received from Ferenczi’s experiences.  I promise to believe everything that can be made to seem the least bit reasonable.  As you know, I do not do so gladly.  But my hubris has been shattered.  I should like to have you and F. acting in consonance when one of you is ready to take the perilous step of publication, and I imagine that this would be quite compatible with complete independence during the progress of the work…

Cordial Regards to you and the beautiful house,

from Your faithful,

Freud

Jung authored a wonderful, gigantic illustrated diary called The Red Book which delves into his personal psyche.  Carl Jung also co-authored an autobiography called Memories, Dreams, Reflections that covers his entire life.  I especially recommend reading the second to last chapter of Memories, Dreams, Reflections entitled “Late Thoughts,” it comforted me quite a bit during a troubled time.  The appendices of the book also has personal letters between Jung and Freud, and between Jung and Emma Jung his wife.