The naked children disporting themselves on a tree somehow lead to the atrocities Goya depicts They look at me and smile. "Everything we do is completely open-ended," says Dinos.So is it any good, their art? Well, yes. It's all well-made, it sticks in the mind and it is a little disturbing. And it provides icons for your thoughts to wander around: it has, in other words, and like other art, that Rorschach ink-blot quality, although its nature is more that of a psychological guided missile.

I give them mine: it's a variation of Great Deeds, but appears to show an event prior to it. It is about infant sexuality, despite the missing genitals, about jouissance. Of Year Zero Dinos says, "I think we've been quite generous with this piece," meaning that it's wide open for different readings. It was a close-up and blow-up of their previous Disasters of War, in which plastic toys were re-modelled into a tabletop version of Goya's famous series. One of Mummy's nipples is a vagina.But interpretation is an endless exercise. But this adds up: in Mummy Chapman, and in the sexual world of the Chapmans' work in general, there is a kind of sterility Testicles and breasts are not much in evidence.

Now Great Deeds has been succeeded by Year Zero, a Garden of Eden-ish scene with three naked, playing children taking the place of the three mutilated men of Deeds No wounds this time, except one cut knee. No genitals either, and this from the artists whose representation of their mother - Mummy Chapman - was all genitals: penises and vaginas appearing like disease all over her body. The idea, "let's make it into a sculpture", seems so crazy it's irresistible.With Great Deeds Against the Dead, a large work of two years ago, they remade a Goya etching, reworking it using mannequins. And for some reason he wants him to be sci-fi, so he paints him silver Such is the Chapmans' art. Their sculptures are art-jokes, rather than any other kind - not jokes about desire, or genetics, or Freud, or any other subject their pieces raise in discussion Drawings are turned into solid objects. From his wounds he drips fake blood, which trickles down his body and splashes into a bucket. It runs back up a plastic tube with the aid of a pump, the noise of which fills the room He is a Marvel Comics hero and a Jeff Koons gone wrong.

Renaissance, futuristic, and a verbal quip: buckets of blood. He is utterly absurd.He is also rather beautiful, which most Chapman sculptures aren't. He is the complete realisation of an idea in a little boy's mind: a boy who has a model and wants to torture him. He is on a silver plinth on the ceiling, and his long black hair hangs down. He is an upright statue, but his torture involves being suspended: he's an artistic failure, a ridiculous aesthetic resolution of something.

bermensch and Cybericonic Man have personalities, unlike most Chapman humans, who tend to be permutations, specimens. These two are heroic. Hawking is Hawking, pitiful and noble in his post-quantum, post-accident glory, and Cybericonic Man is a martyr. His skin is silver, except where chunks of his flesh have been cut off His wounds are red He stands, weight on one leg, a cool Saint Sebastian His hands are tied behind him to a post. It has something in common with a previous work, bermensch, their model of Stephen Hawking in his wheelchair and placed on a rock. This piece has never been shown in Britain and the brothers complain that press photographers always snap it with its dry ice machine switched off. But is it any good and does it have anything to say? The short answers are: yes and no The longer answers are an art journalist's quagmire. Cybericonic Man, currently hanging upside down from a ceiling in the ICA, may be their best work to date.