THE CENTRAL FACTS FROM THE COURSES YOU ALWAYS MEANT TO TAKE, IN 25 LECTURES

I like to think of Freud as a Victorian explorer, gliding in his hot-air balloon over dense jungle at night. Strange tribes are busy down there; strange rituals are taking place around the scattered fires, which no one else had ever thought existed. He alone has been brave enough to fly here, and now he peers down, restraining his excitement, notepad at the ready to record the distant cries. He can dimly make out the tracks and villages through the gloom.

To Freud this jungle is the strange world of our unconscious, and the way in - those first scattered fires he glimpsed - is through our dreams. This is why he asked his patients, stretched out on the stacked cushions of his couch, to relax, not to be embarrassed, and to call up the memories of their latest dream.

It was appalling stuff. There were fine, upstanding citizens of Vienna walking around who had had visions of murder or desperate lust in their minds just hours before. It was hard to work out at first, for even in the quiet of his study, his patients' conscious minds, aghast at what was being revealed, would try to hold back the worst evidence.

In one dream, an English-speaker reported that the bottom of his shoe fell off. He hurried through the streets, screaming for his wife or friends to help him find it, but they refused. "My sole! my sole!" he cried. The dream seemed to make no sense, until Freud suggested that what he was worried about was his soul - and that this dream was the closest his unconscious could get to revealing it.

Sometimes, though, Freud was less impressive, as in the case of Dora, the now famous 18-year-old who had the misfortune to enter his study one day in 1900. She'd been sent by her father, both because she had an anxious cough, and because she was apparently concerned with an older man, named Herr K.

As the analysis began Freud said straight away that she was in love with her father. She told him, no, that wasn't the case at all, but he insisted. Then he asked about her dreams, and she told him one where, among other things, her father insisted on saving her from a burning house. This could have meant, say, that she was somehow fond of her father. But Freud was insistent: this meant that she loved Herr K.

Next Dora told him about a horrible time, back when she was 14, when Herr K had invited her to his office, then grabbed at her, pressing his "erect member" against her until she had recoiled in disgust. Well, Freud said calmly, her disgust was clearly displaced love. For shouldn't a normal woman be pleased by such a contact? After all, he personally knew Herr K, who was a handsome man. Dora had just displaced her desire upward, to her throat, which is why she had the cough.

Dora broke off the sessions, but Freud wasn't bothered. "The 'No' one hears from a patient with a repressed thought," he wrote, "only registers the repression. If one... disregards it, and continues the work, proofs will soon appear that 'No' in such a case signifies the desired 'Yes'."

The problem arises wherever one authority has insight into the truth, which others, mere mortals, are blocked from because of their delusions. Even with the best will a psychotherapist often ends up working blind - the piercing searchlight reveals no more than the operator's trembling hands - which has led to a sometimes embarrassingly low cure rate.

This flaw didn't matter in 1920s America, where psychoanalysis first took off. It was simply taken as giving a justification to having fun, since you can never tell what damage you might do by holding your inner passion back. Radicals in numerous countries used it to undercut authority, for who would believe the pronouncements of an emperor or king who was subject to these unspeakable passions?

Disillusioned radicals could use it, too. Arthur Miller bitterly remembers his activist colleagues slipping, one by one, into the indulgence of long, private analysis in the 1950s, and giving up on the world around them.

What remains of Freud's ideas? There's the original viewing of the night- revealed depths; the truth-tellings that force themselves out even in daytime slips of the tongue; the whole vision of our shaped-by-childhood traumas, or deep, hidden desires.

For the fact that you can't tell for sure which interpretation of them is right doesn't mean that no interpretation is true; that the unconscious is not, really, constantly trying to fight its way out. That's the final twist, the ultimate, obscuring tree cover over Freud's new continent. We can peer down all we want, but because of those inherent distortions, we'll never know, for sure, the meaning of what we've seen.

Tomorrow,

Quantum Mechanics

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