On a Saturday morning in November 1966, Tom Phillips picked a book at random from a pile of novels at a house-clearance sale in Peckham Rye. Phillips had never heard of W.H. Mallock’s A Human Document (1892), but he liked the title and the yellow cover and handed over threepence. Back at his kitchen table, Phillips began a process of remaking or ‘treating’ the book: by painting over most of each page with acrylic gouache or ink, he left visible a stream of text which, in dialogue with the images he added, told a new story. By folding the title-page, Phillips contracted the words ‘a human document’ into a neologism he liked: ‘a humument’. ‘An earthy word,’ he writes in the afterword to this fifth edition, ‘I like even the effortful sound of it.’A Humument is a strange, beguiling work, which Phillips found within Mallock’s long-forgotten novel. A Human Document opens: ‘The following work, though it has the form of a novel, yet for certain singular reasons hardly deserves the name.’ Phillips obscures most of the first page with a blue and orange arrow, leaving a few scattered words that cohere into a version of the opening of Virgil’s Aeneid (‘I sing of arms and of a man’): ‘I sing a book of the art that was/now read on/of mind art/though I have to hide to reveal.’ He treats each page of Mallock’s novel in this way, effacing most of the text, generally by painting, occasionally by cutting, slicing, or even in one instance burning the page, to leave an alternative narrative. Phillips’s revealed story was in one sense always there in Mallock, just lost amid the torrent of other text. This is authorship as pruning, a process of erasure or cutting away that finds in the buttoned-up A Human Document a teeming world of humour, sex, sadness and art that would have baffled and shocked the conservative Mallock.