It was, said June Campbell as she began her lecture, only the second time she had been asked to give a talk to a Buddhist group in this country since her book, Traveller in Space, came out three years ago. Small wonder. The topic of her talk was "Dissent in Spiritual Communities", and you don't get much more potent types of dissent than hers. For she not only revealed that she had for years been the secret sexual consort of one of the most holy monks in Tibetan Buddhism - the tulku (re-incarnated lama), Kalu Rinpoche. She also insisted that the abuse of power at the heart of the relationship exposed a flaw at the very heart of Tibetan Buddhism.
This was heresy, indeed. To outsiders, the Rinpoche was one of the most revered yogi-lamas in exile outside Tibet. As abbot of his own monastery, he had taken vows of celibacy and was celebrated for having spent 14 years in solitary retreat. Among his students were the highest-ranking lamas in Tibet. "His own status was unquestioned in the Tibetan community," said Ms Campbell, "and his holiness attested to by all."
The inner circles of the world of Tibetan Buddhism - for all its spread in fashionable circles in the West - is a closed and tight one. Her claims, though made in a restrained way in the context of a deeply academic book subtitled "In Search of Female Identity in Tibetan Buddhism", provoked what she described as a primitive outpouring of rage and fury. "I was reviled as a liar or a demon," she said during a public lecture last week at the non-sectarian College for Buddhist Studies in Sharpham, Devon. "In that world he was a saintly figure. It was like claiming that Mother Teresa was involved in making porn movies."
But it was not fear of the response which made her wait a full 18 years before publishing her revelations in a volume entitled Traveller in Space - a translation of dakini, the rather poetic Tibetan word for a woman used by a lama for sex. It took her that long to get over the trauma of the experience. "I spent 11 years without talking about it and then, when I had decided to write about it, another seven years researching. I wanted to weave together my personal experience with a more theoretical understanding of the role of women in Tibetan society to help me make sense of what had happened to me."
What happened was that, having become a Buddhist in her native Scotland in the hippie Sixties, she travelled to India where she became a nun. She spent 10 years in a Tibetan monastery and penetrated more deeply than any other Westerner into the faith's esoteric hierarchy. Eventually she became personal translator to the guru as, during the Seventies, he travelled through Europe and America. It was after that, she said, that "he requested that I become his sexual consort and take part in secret activities with him".
Only one other person knew of the relationship - a second monk - with whom she took part in what she described as a polyandrous Tibetan-style relationship. "It was some years before I realised that the extent to which I had been taken advantage of constituted a kind of abuse."
The practice of Tantric sex is more ancient than Buddhism. The idea goes back to the ancient Hindus who believed that the retention of semen during intercourse increased sexual pleasure and made men live longer. The Tibetan Buddhists developed the belief that enlightenment could be accelerated by the decision "to enlist the passions in one's religious practice, rather than to avoid them". The strategy is considered extremely risky yet so efficacious that it could lead to enlightenment in one lifetime.
Monks of a lower status confined themselves to visualising an imaginary sexual relationship during meditation. But, her book sets out, the "masters" reach a point where they decide that they can engage in sex without being tainted by it. The instructions in the so-called "secret" texts spell out the methods which enable the man to control the flow of semen through yogic breath control and other practices. The idea is to "drive the semen upwards, along the spine, and into the head". The more semen in a man's head, the stronger intellectually and spiritually he is thought to be.
More than that, he is said to gain additional strength from absorbing the woman's sexual fluids at the same time as withholding his own. This "reverse of ordinary sex", said June Campbell, "expresses the relative status of the male and female within the ritual, for it signals the power flowing from the woman to the man".
The imbalance is underscored by the insistence by such guru-lamas that their sexual consorts must remain secret, allowing the lamas to maintain control over the women. "Since the book was published, I've had letters from women all over the world with similar and worse experiences."
So why did she stay for almost three years? "Personal prestige. The women believe that they too are special and holy. They are entering sacred space. It produces good karma for future lives, and is a test of faith."
The combination of religion, sex, power and secrecy can have a potent effect. It creates the Catch 22 of psychological blackmail set out in the words of another lama, Beru Kyhentze Rinpoche: "If your guru acts in a seemingly unenlightened manner and you feel it would be hypocritical to think him a Buddha, you should remember that your own opinions are unreliable and the apparent faults you see may only be a reflection of your own deluded state of mind... If your guru acted in a completely perfect manner he would be inaccessible and you would be able to relate to him. It is therefore out of your Guru's great compassion that he may show apparent flaws... He is mirroring your own faults."
The psychological pressure is often increased by making the woman swear vows of secrecy. In addition, June Campbell was told that "madness, trouble or even death" could follow if she did not keep silent.
"I was told that in a previous life the lama I was involved with had had a mistress who caused him some trouble, and in order to get rid of her he cast a spell which caused her illness, later resulting in her death.
There are those Buddhists, like Martine Batchelor - who spent 10 years as a Zen Buddhist nun in a Korean monastery and who now teaches at Sharpham College - who insist the religious techniques the Buddha taught can be separated from the sexist, patriarchal and oppressive culture of many Buddhist countries. But June Campbell is not convinced.
"You have to ask what is the relationship between belief and how a society structures itself," she said. In Tibetanism, power lies in the hands of men who had often been traumatised by being removed from their mothers at the age of two and taken to an all-male monastery. "Some were allowed visits from their mothers and sisters but always in secrecy - so that they came to associate women with what must be hidden."
But there is more to it, she believes, than that. Teaching at Sharpham last week she gave the students a whole range of material about different kinds of feminism - from the political to the psychotherapeutic. She then asked them how it relates to the fact that there are no female Buddha images, or to why in Tantric sex images the woman always has her back to the viewer, or to why Buddhist women are told to pray that they will be reborn into a male body in their next life - for only in a man's body can they attain full enlightenment.
"Once I started unravelling my experiences, I began to question everything," she said. That meant not just the actions of a particular guru, but the very idea of the guru. She began to wonder whether the Tantra was just a fantasy, and whether there is really any difference between Tantric sex and ordinary sex. She questioned the very concept of enlightenment itself and the practice of meditation. "I realised that in order to be myself I had to leave it all - completely and utterly."
`Traveller in Space' is published by The Athlone Press at pounds 17.99