Well, since you insisted on bringing it up...

Most modern psychiatric and psychological theories can be traced to Sigmund Freud.

His ideas and their variants not only permeate our psychological and behavioral sciences, they have an enormous influence on our medical and therapeutic practices, arts and literature, popular culture, and even our legal statutes. Freud and his followers still dominate the science today. Some of them consider themselves his critics, but they still share much more with him than they offer alternatives. Sigmund Freud was a visionary and a genius, he was the first to propose a consistent theory of the human mind, a decided advance over the religious superstitions and phrenological nonsense that preceded him, but he was essentially the first. In many ways, his ideas were brilliant but premature, about as simultaneously useful and misleading as Ptolemaic astronomy was in Pre-Copernican times.

Freud based his theory of personality on a scientific model that was advanced during his time: hydraulics. Later there came other analogues, such as a telephone switch board, or an analogue computer, or today's digital processor. Today, we even speak of holographic and even quantum models. But in his time, he relied on the dominant technology of the late nineteenth century: steam.

Freud's conception of the brain was essentially a hydraulic one, "pressures" built up and had to be "released" to avoid dangerous "explosions" or "leaks". Powerful forces are on the move in the Freudian brain model, forces that can be led astray, misdirected, or alternatively, intercepted and guided in preferred directions during treatment. The entire discipline of psychology today is permeated with this paradigm, it influences its thought and even its language. Pressures have to be vented, after all, or they lead to catastrophic releases, don't they? This way of thinking is almost undeniable, it is linguistically satisfying, it sounds right. At least it does in English, and I presume, in German, languages which rely heavily on metaphor. In Spanish, translations of Freud sound ridiculous. It is no surprise Freudian psychology never caught on in the Romance Language speaking nations.

Do computers really break down when faced with a logical contradiction? Maybe they did for Capt Kirk, but we know better. Neither does the human brain malfunction when holding conflicting thoughts. In fact, its designed to work that way. I hate to lapse into the vernacular, because it sounds so "unscientific", but if people are acting crazy you can't talk to them and cure them. You can't ask them to talk about their dreams or ink blots or word-associate them or discuss their mother and expect them to suddenly be cured. There are no valves you can open or close to release the pressure. There is no pressure.

Mental illness is like any other before the age of antibiotics and modern surgery, it either goes away on its own, with little help from us, or nothing we can do helps the patient; he stays sick or gets worse. Sometimes, if we're very lucky, we can treat a chemical imbalance and correct the problem, but those cases are mostly luck, the psychological equivalent of slapping the dashboard to get a car radio to work.

The practice of psychiatry today is about where medicine was when Harvey discovered the circulation of blood. It has made great advances, but it essentially does not have a clue what it is doing. There is no disgrace in this, the human brain is the most complex thing in the known universe, but in my opinion, the artist can tell us more about its operation and its failure than all medical science. Shakespeare has revealed more about the human soul than Freud ever could.

I have no problem with the shortcomings of psychology, it's task is infinitely harder than that of the physicist. But I do have a problem with psychiatrists having the authority to commit or release mental patients, give expert testimony in court, prescribe chemicals, or influence legislation. And I find their influence in literature and the arts scandalous. Now I concede individual practitioners can be very skillful and successful, but witch doctors and shamans often can treat many maladies successfully in primitive societies, merely by knowing human nature and applying common sense and experience to trial and error.