The Australian Steve Toltz’s exuberantly entertaining debut novel is the kind that poses a conundrum for your humble hack. Reviewing comic novels is rather like playing tennis with a soap bubble — if the thing’s any good, you feel like just saying, “Hey, this is funny — go away and read it”, which is hardly FR Leavis. And if it isn’t any good, then you come on heavy and sound like a curmudgeon. For what could be more blameless than trying to make people laugh?

Fortunately, there is plenty to laugh at in A Fraction of the Whole — and also, goodness knows, there is plenty of plot, since the book has the dimensions of a family Bible (if this a fraction — my God, what is the whole?) and the narrative pace of a puppy with attention-deficit disorder.

But it also has a heart: the story of a father and son — a crazy father and (hence) a crazy son. Martin Dean, the father, is a philosopher, but not the kind of philosopher who gets to be a professor and wear a tweed jacket. He is “a philosopher who thought himself into a corner” — the sort of philosopher who takes his son out of kindergarten to read him Nietzsche and the letters of Van Gogh, and who writes letters to the local paper suggesting schemes for world government.

Growing up in suburban Australia, the son, Jasper, understandably feels a certain filial ambivalence (his mother is off the scene, having been blown up by the mafia in Paris — I won’t go there), and the book is an exploration of that ambivalence, and of the origins of Martin’s peculiarity. The big influence on Marty’s life is his brother Terry. Unlike Marty, and to Marty’s deep and unending chagrin, Terry succeeds in making his mark on the world (or at least Australia). He graduates from a promising career as a bank robber to becoming the country’s most famous and heroically Australian serial killer. For when this most sporting of nations suffers a spate of sporting scandals (drugs, bungs etc), Terry steps up to the mark and does what every good Australian would secretly love to do — inflicts a gruesomely appropriate death on each and every sporting evildoer.

The psychopathic Terry turns up again towards the end of the book, grossly overweight and sitting in the Thai jungle — a bit like Marlon Brando in Apocalypse Now, only with jokes. But before that, it is Marty’s attempts to make his mark that take centre stage. As a child he institutes a town suggestion box that results in the incineration of the entire community. He publishes a How To book for aspiring criminals. (Burn, Baby, Burn: Arson and You, Motiveless Crime: Why? Manslaughter: Oops! and Escaping Custody: Walk, Don’t Run are among the chapter headings.) And he finally achieves national notoriety when his scheme to make every Australian a millionaire goes pear-shaped.

Jasper observes these (and many, many other) escapades with wonder and horror. I can’t help feeling that the über-father-son relationship of modern culture was an influence — I’m talking, of course, about Homer and Bart Simpson. Marty Dean is Homer Simpson with philosophical attitude. Still, if you’re going to have influences, it’s best to go with the best. My inner curmudgeon grumbles that the novel could have been shorter — some of the jokes are plain silly. But A Fraction of the Whole is nevertheless a grand achievement and the debut of a great comic talent. So, this is funny: go away and read it.

A Fraction of the Whole, by Steve Toltz

Hamish Hamilton £17.99 pp711

Buy from BooksFirst for £16.19 with free delivery in the UK

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