There are plenty of bottoms in this book — “undulating” on girls in a music video, “abundantly feminine” on head-scarved women in a gym, “formless” on suburban mothers and daughters on an Oxford Street shopping trip, “flat, flat spatchcocked” on junkie girls in Soho, “cruelly exposed” on a woman in hospital who will soon be dead. They are there because Justin Cartwright is exploring fundamental questions — how do we reconcile our bodily urges with our mental visions, why are we so different when we share the same human form, what sits beneath our desire for the sacred and the sacramental?

There are four central characters. David is a retired TV news anchor whose wife has recently died. His mortally ill brother Guy lives in South Africa. His son is an up-and-coming lawyer, ­married to Rosalie and seeking diversion from their failure to have a child by having an affair. His daughter Lucy works for an art dealer and is trying to escape the demands of her unstable ex. David meets old friends, visits his brother and remembers a girlfriend who drowned with his accidental connivance during their participation in a film of Doctor Faustus.

The narrative moves skilfully through times and places and points of view. There are sharp pictures of modern London, often captured in brusquely pitiless ­formulae. A garden is “a cat’s ­lavatory with self-seeded trees”, a gym customer has the “authentic voice” of “grievance, obscenity and self-pity”, an artist from an organic cafe has “free-range” breasts and “Rapunzel hair”, “traditionally the mark of the free spirit”. There are some fine descriptions of city skies, with paired adjectives (“muted, crawling” or “surly, gaseous”) doing a lot of fastidious work.

The scenes in Africa are fewer, but are realised with attentive and intelligent care. The ­nullity of the landscape makes London seem a place of lavish excess, but the opposition is not a simple one between austere ­virtue and profligate vice. Guy’s killing of a snake contradicts his irritating assumption of spiritual authority, while David’s attempt to empty his mind is ­overtaken by a chaotic flood of guilt-tinged images.

Cartwright expects his readers to pick up allusions to Donne, ­Tennyson, Frost, Joyce, Dylan ­Thomas and especially Hopkins, whose sonnet The Windhover ­echoes throughout. Sometimes he challenges conventional notions of literary propriety or detachment. Gordon Brown is “this rumpled old political wheeler-dealer, with the coelacanth mouth and just the one eye”, while the shopping suburbanites are snootily rebuked for their “world of white-leather sofas and fast food and criminal hairdressing”. The fiercest criticism, however, comes when one of David’s friends denounces “all novels written since 1940” in a page-long, scurrilous, often all-too-true and hilarious rant.

The serious central themes are interconnected but overstated. An early suggestion (“being is what we lack”) develops into a pre-occupation with “surrendering the troublesome self”, dissolving “the barriers between the immanent and the transcendent worlds”, “the understanding that people everywhere are in thrall to delusion”, the gnostic view that “we are all potentially divine but trapped in a material world”, “the tide of the numinous”, the possibility of making a Faustian bid to know the mind of God. David even ascribes his brief sexual encounter with his daughter-in-law not to any physical impulse, but to his inner shaman.

These unworldly abstractions don’t cancel the slowly accumulating power of the many small scenes in which the realities of friendship, love, ageing and the approach of death are brought believably onto the page. We get to know David’s family — their fleeting disloyalties, conscious self-deceptions, unspoken resentments, half-acknowledged motives of sentimentality, and their selfishness. The moral clarity is refreshing but not demeaning. The book recognises that life is not singular but plural. Ed believes that irony is “indispensable to being human”, but knows, too, that his mother never understood it. This generous ambiguity rests the book on a very firm bottom

To Heaven by Water by Justin Cartwright
Bloomsbury £16.99 pp320

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