A central tenet of Buddhism is that the self is illusory. We are more than our conscious minds and we are wrong to think of our autobiographical self as a 'true self'. Freud's 'ego' is also illusory, insofar as it generates a misleadingly comprehensive sense of selfhood, whereas in reality it is only a small part of a much larger, opaque totality.

Freud's technique for interpreting dreams was very straightforward. When a patient recounted a dream, Freud would isolate thoughts, feelings, conversations and images, and use each of these elements as a starting point for exploratory discussions and free association. Repressed material was then likely to 'fall in' to the flow of the patient's

We must reclaim as much of ourselves as we can. We must discover a personal morality shaped by experience rather than 'tribal' prohibitions. We must wrestle our minds free of prehistory so that we can make better, rational choices.

The phenomena that interested Romantic philosophers might appear somewhat arbitrary. Mental illness, ghosts, animal behaviour? But anomalous and exceptional phenomena can be thought of as a point of weakness between the perceived material world and something greater beyond.

In fact, it is possible to read The Interpretation of Dreams as a first-person, experimental novel; a book about a late nineteenth-century bourgeois doctor's obsessive search for the solution to an ancient mystery. His single-mindedness is vaguely reminiscent of Ahab's obstinate pursuit of the great white whale in Moby Dick. As the quest proceeds,

Freud declares that there is 'something innate underlying perversions', but 'it is something innate in everyone'. Children are not born pure and corrupted by the world. In fact, they are born perverse and checked by the world's civilising influences. Freud's theory of sexual development reverses a way of thinking about children that dates back to

Novels set within dreams or in worlds that have become dreamlike are now a recognisable literary genre; authors such as Hermann Hesse, Anna Kavan, Angela Carter, Kobo Abe, Kazuo Ishiguro, Haruki Murakami and Vladimir Sorokin have all produced outstanding examples.

The philosopher Ludwig Wittgenstein found Freud's dream theory logically inconsistent. How can a wish be fulfilled in a dream if the dreamer isn't aware of having had that wish in the first place? And how can a symbol function as a symbol if the dreamer doesn't know what it is supposed to be symbolising? The simple answer to these questions is that

Freud was a modern alchemist who reformulated medieval demons as complexes and Darwinian imperatives. He translated all things devilish - lust, violence, cruelty - into terms that were compatible with twentieth-century thinking.