This book is a delight to read, and a joy to look at. And if there is a lesson to be taken from it, it's this: every gallery should have an Ashraf Jamal as its guide, and every culture needs a Lien Botha to document it.

Jamal's essay on Botha is lucid, incisive and original. Take this description of Botha's work as an example: "If sometimes beautiful, if on other occasions beatific, its abiding register remains a tonal darkness and visceral discomfort."

You'll seldom read a better description of that uncomfortably contested area in which art works, where the artist is always compelled to present an ugly thing beautifully. It's the type of succinct analysis that many people would appreciate in galleries, where you're often confronted by art that is almost too powerful to grapple with.

Crudely (very crudely) speaking, there are two ways of appreciating an artwork. You either wrestle with its meaning on an intellectual level, or you appreciate it aesthetically. Jamal brings us both. He knows about art, but he also knows how to like art. So although his essay, Music of Silence: The Art of Lien Botha, traverses a juicy spread of postmodern and art theory, it also draws on practical examples from literature, art and empirical readings.

We move from the opening sentence, "Giorgio de Chirico detested music", to the gentle closing suggestion, "If you listen with your eyes you will hear the artist's tremulous song." The distance we cover in between those two points is sometimes instructive, but always enjoyable.

The essay's force is greatly aided by the simple design of the book, and the judicious selection of Botha's works that are reproduced. I've always loved Botha's works, but until I saw the full range laid out here I didn't comprehend the system of thought behind them.

There's a heft behind what Botha does, a solid underpinning of rigorous philosophy. Jamal refers to Botha's "governing belief in the possibility of wholeness", but also to the abiding condition of her art: that "wholeness can never be forged, only intimated". As you page through this book, you can see this struggle played out in beautiful, and sometimes heart-rending detail.

It would be wrong, however, to characterise Botha's oeuvre as simply an artist's search for psychic resolution. As Jamal points out, Botha also documents history, and is a commentator on what we could loosely term the South African condition.

Her 1996 exhibition, The Washing Line, is an appropriate example of this. On a washing line strung up in the Cape Town Castle, Botha hung white sheets of material printed with images of "South Africa's brutalised body politic". A simple idea, but one of force and beauty, summed up by Jamal as "the country's dirty laundry has been hung out in public". I will never forget the impact of seeing this artefact of domesticity, moving closer to it in a puzzled fashion, and suddenly seeing the images that were hanging there to dry.

If there's one facet of Botha's art that Jamal misses, it's the humour. As with a writer like JM Coetzee, whom Jamal draws on as part of his explication, Botha's work often has an undercurrent of absurdity. The subject matter that Botha works with, the histories and horrors of South Africa, cannot be represented without this tinge of humour. Perhaps that's because it is South African, or because humour is an inevitable safety valve when dealing with such emotive subject matter.

Whatever the answer, this book amply demonstrates Botha's status as a fine artist. More, it makes a very convincing case for regarding her as potentially a great artist.