Seeds of Greatness, by Jon Canter<br/>What Happens Now, by Jeremy Dyson

Jon Canter is a north-London Woody Allen. I haven't laughed so much in years - and then realised that I'd felt and thought hard too.

Seeds of Greatness is worth reading for its Jewish jokes alone. When its Bad Hero, Jack, gets fired for sleeping with a client, its Good Hero, our narrator, Dave, says that he should have been made the salesman of the month instead: "Who else could sell two patio doors to a woman who has one patio?" Photographing a famous actress with huge, shiny eyes, Dave says: "It's as if she's had her eyeballs lifted". And when Jack becomes rich, and adds endless wings to his house - an exercise wing, a guest wing, a children's wing - there's also a wing for things that don't fit in the other ones: "a wing without portfolio, a wing wing".

Why are these jokes so Jewish? Because they're mocking, verbal, and Talmudically precise. So Dave, who works in a bookshop, chides himself for comparing stacks of books to sunbathers: "Sunbathers are never in stacks. You can't sunbathe with a sunbather on top of you". He's even better when he's not being funny. Take this, about the difference between his customers and himself, the professional, when returning books to their shelves: "They angle a book into a gap. They tilt the book backwards and, leading with the bottom edge, gingerly wedge and lower. I use a straight left. I slam it in the gap. Bam. The books on either side don't feel a thing." Observation this good, even of shelf-stacking, is art.

Jack and Dave are two Jewish boys from Golders Green, but their pairing is universal: Jack worldly, amoral and confident, fated to succeed, Dave timid and scholarly, fated to fail. But things are not so simple. In fact Jack has nothing to sell but himself, and until he finds his niche - as a television talk-show host - Dave has fun with his awful ideas: an underbed storage unit that won't fit under a bed; a string of kosher vegetarian restaurants, about which someone who is declining to invest writes: "Dear Jack, Jews eat meat". Though Dave helplessly admires Jack, he also despises him ("All friends, surely, are schadenfreunds") - his ignorance, his vulgarity, his self-absorption. And though Dave satirises himself - his timidity and pedantry, his choice of failure before it can choose him - he thinks himself better than Jack: more intelligent, more sensitive, nicer. Which he is. "That," he says, "is why I'm his biographer."

This brings us to the next butt of Canter's satire: biography. When Jack dies, Dave is asked to write his biography. He agrees, but never does - this is his Jewish version of refusal. Instead he writes this anti-biography. It mocks the necessity of the Dream ("He always dreamed of being a sprinter; before he was old enough to walk, he sprinted") and the years when nothing happened. And it provides one of the best arguments for biography, and one of the best attacks on it. Respectively: "Every moment of your life your actions express your character and destiny in the most brutally obvious way... It's all there, always"; and "This is the vanity of biographers - to think they're human torches of truth when they're journalists with more space." Ouch. Bingo.

What Happens Now is a Jewish story too, but that's the problem. Seeds of Greatness is wonderful on Jews - not just funny (a camera so simple it says: "can be used by Jews"), but serious too (on Jewish families wanting either only good news, or only bad). Alistair Black, the hero of What Happens Now, is said to be Jewish, but for all we see of his character and background he might as well be Scottish, as his name suggests.

He is a natural actor, and when the BBC comes looking for child actors, Alistair is chosen. He is cast as a young Jewish boy who dies in the Holocaust, and he falls in love with Alice, who plays his sister. Something nasty happens to Alice; years later Alistair does something nasty too, and then dies. I know it's because he failed to protect Alice, but what does it mean? Is young Alistair's constant fear meant to be a collective unconscious memory? Is that why he "instinctively" holds his hands up, like the little boy with the yellow star in the famous photograph? This is a gratuitously violent book, not dignified by its Holocaust borrowing. On the contrary.

Carole Angier's biography of Primo Levi is published by Penguin