WHY is it one is often tempted to refer to a writer's latest book as if the author's name were a trademark and his or her novels a line of sportswear: for example, ``Have you read the new Muriel Spark?'' It's no secret that writers evolve personal styles and map out their own specific territories of subject matter. In the case of Muriel Spark, the ``trademark'' instantly seems to summon up cool, polished, witty high comedy with darkly ironic undertones that shade into black comedy and the bizarre. Things are not what they seem, and sudden death lurks just around the corner.
Spark is the author of nearly 20 novels, plus poems, stories, drama, and biographies of John Masefield and Mary Shelley. Her best-known novel, ``The Prime of Miss Jean Brodie'' (1961), was made into a film starring Maggie Smith as the acerbically charming schoolteacher who exerts a devastating influence on her favored pupils. Her recent ``update'' of the story of Job, ``The Only Problem,'' received a mixed reception, quite unlike the praise that greeted her previous novel, ``Loitering with Intent'' (1981), and her most recent, ``A Far Cry from Kensington'' (1988).
What both these engaging books would seem to demonstrate is that, far from wilting in the presence of a sympathetic (if self-justifying) narrator/heroine, Spark's delicious sense of irony grows keener with a touch of human warmth. It's when she withdraws into her chillier modes that her irony sometimes becomes heavy-handed and her wit congeals from quicksilver into something more sluggish.
`SYMPOSIUM'' is an elegantly constructed little novel, as carefully arranged as the dinner party that provides it with its title. But if the unspeakably banal chatter that goes on at the dinner party in this novel is meant to represent a modern-day version of Plato's ``Symposium,'' Spark is certainly in deep trouble. More likely, it is intended as an ironic contrast.
The characters who assemble at the London home of artist Hurley Reed and his longtime mistress Chris Donovan are a trendy mix of urban types. They include Lord and Lady Suzy, a middle-aged peer and his new, much younger wife; Roland Sykes, ``a melancholy gay'' who researches genealogies; his cousin Annabel, a television producer; Ernst and Ella Untzinger, who keep separate residences, she in London, he in Brussels, where he serves on a finance commission for the European Community. Then there are the newlyweds, William and Margaret Damien. He is the heir to a large fortune. She is a romantic-looking redhead who exudes sweetness and altruism, but whose background is rather murky.
Lord and Lady Suzy have just had a robbery at their home. Much to her annoyance, he keeps comparing it to being raped. Margaret Damien gently suggests there's a religious virtue in being divested of one's worldly goods; Roland Sykes points out that robbery involves a crime; divestiture does not.
If the conversation at this symposium is scarcely clever, let alone platonically edifying, the characters are as insubstantial as their talk. This being so, it is hard to feel much of a stake in anything that happens to them.
The plot - as precise (and monotonous) as clockwork - is propelled by two main questions: Who is behind the string of recent robberies and what is the story behind Margaret Damien, nee Murchie, daughter of an eccentric Scottish family? The answers will surprise no one who is familiar with Spark's previous novels, and, indeed, will probably not be much of a surprise to those who have never read her work before.
Which is not to say that ``Symposium'' is anything but a polished, very professional performance: a bright divertissement with the tonically bitter aftertaste we've come to expect from Muriel Spark. But in neglecting to go below the surface of the characters, it fails to get under the skin of the reader.