Born in Buenos Aires, raised in Israel, a Canadian citizen, currently resident in France, the author of dozens of books and the editor of anthologies, Manguel is a true polymath, and A Reader on Reading is a kind of a primer, or perhaps a masterclass. It's like listening to Barenboim on Beethoven, or perhaps more like being the child in the DH Lawrence poem who sits beneath the piano, "in the boom of the tingling strings / And pressing the small, poised feet of a mother who smiles as she sings". The book is a compilation of reviews, lectures, essays and reminiscences from various publications and countries. The range and complexity of Manguel's sympathies and readings is extensive and baroque; a concerto grosso.

Manguel begins, in the essay "A Reader in the Looking-Glass Wood", in childhood. "When I was eight or nine, in a house that no longer stands, someone gave me a copy of Alice's Adventures in Wonderland and Through the Looking-Glass." The house is gone, but the memory of the book remains, "printed on thick, creamy paper that reeked mysteriously of burnt wood". Manguel returns constantly to the idea of reading both as a place of refuge and as an escape route. In "Aids and the Poet" he writes that "For a reader, this may be the essential, perhaps the only justification for literature: that the madness of the world will not take us over completely though it invades our cellars . . . and then softly takes over the dining room, the living room, the whole house." In "The Library of the Wandering Jew" he suggests that books are the compasses that guide us both in our self-discovery and in our exploration of the world.

But most of us know this already, though of course we couldn't have expressed it so. (We like to think we could have done, but we didn't, and we haven't.) Obvious or not, these are only Manguel's starting points  or his cardinal points. What he discovers and where he travels to is what counts, and he goes far and wide, high and low  to Borges, to Cervantes, to Homer, to pornography, to ebooks, to the history of reading and the future of reading, and back home again. In a casual aside he usefully defines his theory of interpretation thus: "the intelligent and inspired reconstruction of the text, using reason and imagination as best we can to translate it on to a different canvas, extending the horizon of its apparent meaning beyond its visible borders and the declared intentions of the author".

It is very rare indeed for someone to have devoted their lifetime to making these complex and delightful reconstructions, to sharing and reporting on their experiences as a reader; much rarer, say, than the many who devote themselves simply to criticism, to judgment or to commentary. It's so rare, in fact, that it's difficult to know what to call it. Manguel might best be described not so much as a critic but rather as a devotee of reading; one thinks of Susan Sontag, or of Clive James  observers, admirers, enthusiasts. This enthusiasm leads to what one might perhaps describe as a sentimental strain in Manguel's writing, though it might also accurately be described as morality, the imaginative extension of oneself and one's sympathies to others. In his revealing essay on erotic literature, "The Gates of Paradise", he argues that in "reading or making love, we should be able to lose ourselves in the other, into whom  to borrow Saint John's image  we are transformed: reader into writer into reader, lover into lover into lover."

Ian Sansom's Mobile Library novels are published by HarperPerennial.