So Lillie was a woman in a glass case - put there in the first place, by painters and poets for her flawless beauty, and kept there by her own determination, long after their admiration and her perfection had waned. The problem for her biographer is how to get her out - how, at any rate, not to be just another visitor, nose pressed to the glass, viewing the front that Lillie chose to present to her public.
The best way of doing this would be to climb into the case alongside her; to ask, and answer, the question, why was she there? But any reply would be the result of speculation and speculation is not fashionable any more. It makes the reader nervous and the reviewer open his mouth wide in horror.
This is strange in an age where we are generally and habitually psychology-friendly. Speculation does not need to be unfounded. To read a primary source, a diary or a letter, is to eavesdrop on a direct communication. To read a contemporary memoir is to listen to the first-hand account of a friend. Both can lead to a knowledge of their subject that is personal, a form of friendship of our own.
Biography is a curious hybrid. It combines historical method with emotional response. Its promise is familiarity and its practice betrayal. How could it be anything but personal? Why do we worry so much about being unobtrusive and impartial? Why do we strive after autopsy when we might instead create a ghost? Since we live in the heads of our friends, surely we should dare the same with our ancestors. Speculation, if it is conscientious and informed - if it is an attempt to understand, to explain but not excuse - is, quite literally, invigorating. It is one of the tools for bringing the past to life.
There are some subjects more suited to this treatment than others. Kings and queens, all those who have changed the course of history, do not need new technique. Their lives are happily told within the established chronological framework of recorded events. Lillie Langtry's is not. She was whirled to fame at the age of 24. She was the mistress of the Prince of Wales, bore an illegitimate child in secret, skated past bankruptcy, was befriended by Oscar Wilde, became an actress, made a fortune, took up racing, made another, and died lonely and in exile at the age of 76.
What she did is lurid enough. What is more interesting to the modern mind is what it did to her. She is the perfect example of someone for whom speculative biography is a must. If we make no attempt to understand her choices, to unravel the tangle of her motivation, she will remain the museum piece that she was to her contemporaries.
Whether or not we recognise the challenge, it is time to expand. Our past is receding faster and faster. It ought to be possible to take a deep breath, to take confidence in the unchanging nature of human experience, and set up a new form of biography beside the old - one that will be looser, less tied to chronology, more thematic, and expressive of its own dynamic, full of reaction and speculation. There will always be much that will be wrong, but then, is anything ever exclusively right?
Laura Beatty is the author of `Lillie Langtry: manners, masks and morals' (Chatto and Windus, pounds 20)Reuse content