Sigmund Freud belonged to the psychoanalytic part of the school of thought. He specialized in neurology. He was apart of the Victorian era; the era of high morals and modesty. He studied the human mind more than anyone else before him did.
Freud allowed his patients to come in and speak freely on his famous couch.
He did not believe in the physical methods that other people have used to relieve demons from their patients' heads.
He also developed a graph the unconscious mind, using an iceberg as his example saying that the conscious mind is the small above water part of the iceberg and the unconscious part is the large part beneath the water.