The presence in David Cronenberg's new film, A Dangerous Method, of Keira Knightley as Sabina Spielrein (Carl Jung's patient and lover) ensures we will hear more about the analyst Jung's affair: the impact on his marriage, how Spielrein shuttled between Jung and Sigmund Freud – the two narcissistic oligarchs of the early psychoanalytic world (a compelling emblem of the belittlement of women's role in intellectual endeavour, then and now). And finally, how this made the rupture between the men, which was always on the cards, into an inevitability. Sex, not the theory of sexuality, is going to be the main interest.

Sadly, there is unlikely to be much focus on what Jung actually said and stood for. Yet if the last century has been called "the Freudian century", there are reasons for thinking that this one could be Jung's. His time does seem to have come.

For a start he invented the term "complex", meaning combinations or clusters of emotional issues and dynamics, drawn from past, present and even the future. This idea rescues clinicians from having to make precise diagnoses, which are not appropriate in connection with mental health. (This questioning of the validity of tight diagnoses such as "depression" or "anxiety" is still alive today.)

Jung also discovered differences between what he termed "introversion and extraversion" and has become the psychologist of choice for reflective, quiet, shy, poetic people who suffer excruciatingly in their more extraverted families and societies.

He had a much more positive view of the human psyche and unconscious than Freud. For Jung, the unconscious is not only full of wild and destructive drives; it is also the source of creativity, spirituality and the capacity for relationships. Similarly, dreams are not the untrustworthy "texts" that Freud deciphered. Rather, they tell the dreamer exactly what is going on in their psyche. In Jung's idea of "individuation", we see a mapping of the relations between an individual and the group or collective (and Jung coined the term "collective unconscious" to indicate what all humans have in common from a psychological point of view).

Today there is a collective agonising over what is meant by "the west". Easy to define in contradistinction to a supposedly fanatical Islam (itself a political and media concoction), what it means to be western is a much more complicated topic that cries out for a Jungian input. Jung saw himself as a sort of therapist for western culture and, if his criticisms of it do resonate with what many Muslims are saying, then that strikes me as all the more significant.

What Jung saw in western culture is very familiar to what its contemporary critics perceive. He despaired of the over-rational one-sidedness of western culture, the way it has got cut off from nature (Jung is the pioneer of what is now called ecopsychology). He hit out at the materialism and loss of individuality in our world, focused on the mind-body split, on mechanical approaches to sex, and the west's loss of a sense of existential and spiritual purpose and meaning. He even, in a characteristic moment of imaginative genius, tried to be the therapist of the Judeo-Christian God, in his iconoclastic book Answer to Job.

Yet as far as Jung's reputation is concerned, it would be wrong to end on an upbeat note. As a Jungian analyst I have always insisted that Jungian analysts and scholars acknowledge and apologise for his antisemitism in the 1930s and try to fix those parts of the theories that are misguided or plain wrong: for instance using the word "parasite" in connection with the Jews, to refer to an alleged lack of a culture of their own and their supposed need to use the forms of other "host" cultures.

Jung defended himself against the accusation that his ideas chimed with Nazi ideology, but to some his expression of regret seemed inadequate and insincere. He helped numerous Jewish psychoanalysts to flee Nazi Germany – yet he was also an ambitious man and saw an opportunity to become the leading psychologist in central Europe in the 1930s: distinguishing Jews from "Aryans" chimed with the politics of Germany and Austria. He was not a crude antisemite. He was an intuitive person and, though his writings on what he called "Jewish psychology" (ie psychoanalysis) are often deeply offensive, there are some nuggets therein that give one pause for thought.

For example, his protest at the imposition of one system of psychology on everyone anticipates today's transcultural and intercultural psychologists and therapists, which makes him an inspiring teacher for therapists struggling to work in a multicultural society. And Jung's musings about how the Jewish people's possession of land, so far from their historic experience, would affect their group psychological functioning contributes in a very challenging way to our understanding of yet another of today's hot political topics – the situation in the Middle East.

In his clinical work with patients he anticipated the "relational turn" in psychotherapy: writing that the therapist was as much in the treatment process as the patient, and stressing the importance of the "therapeutic personality" as opposed to the mechanical application of the technical procedures. He was an alert and compassionate therapist – another reason we should avoid only concentrating on his personal life. Thankfully, A Dangerous Method is an open-minded film that leaves the audience to make up its own assessment of him.

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