Tate Modern's new Duchamp, Picabia and Man Ray exhibition is as exemplary as it is extensive—a personal and philosophical take on 20th-century art history. These three artists were friends, and the exhibition, pursuing a fashionable line in art historical inquiry, emphasises that art is as much the product of interactions between individuals as it is about ideas and theories. Not that theory has been binned: the show also reminds us that these founding Dadaists were also the grandfathers of conceptual art. There has, the Tate rightly boasts, been no major exhibition of this kind in Britain since the Duchamp show of 1966. But there's one thing missing from this landmark exhibition: a free bus service to Milton Keynes. There, in the town's art gallery, is an equally significant show—a retrospective of the Belgian surrealist-conceptualist Marcel Broodthaers, the first in this country since 1980.
The Tate's holy trinity influenced scores of 20th-century artists, but one may argue that Broodthaers (1924-76) was the true heir to their Dada legacy. He was a poet and small-time book dealer until moving into art aged 40, lured, so he claimed, by its greater financial rewards. In the often-quoted text on the invitation to his first show he announced, with Wildean irony: "I, too, wondered if I couldn't sell something and succeed in life. I had for quite a little while been good at nothing. I am forty years old… The idea of inventing something insincere finally crossed my mind and I set to work at once." There followed a 12-year career, in which Broodthaers took Dada's trinity of themes—its anti-art aesthetic, its critique of capitalism and its mockery of the delusions of the avant-garde artist—to new levels. As witty as he was obtuse, Broodthaers achieved swift recognition across the world. With his crumpled features, thick wavy hair and obligatory cigarette, he seemed to have stepped of out of a Godard film; and in his art he exuded the rebellious nonchalance of one of the director's anti-heroes.
Using arcane materials was a speciality of 1970s conceptual artists—Gordon Matta Clark sawed houses in half, Giovanni Anselmo tied a lettuce to a granite plinth, Joseph Beuys covered chairs in fat—and in this respect Broodthaers more than held his own. His works included pots overflowing with mussel shells and metal plaques stamped with the letters of the alphabet, and when staging an exhibition he would liberally distribute houseplants around the gallery, as if it were an office.
The centrepiece of the Milton Keynes exhibition is Sand Carpet (1974; pictured, right), a "sculpture" consisting of a perfectly rectangular carpet of pink sand. Along its edges are the letters of the alphabet neatly sprayed on in black paint, using a stencil. In the centre of the "carpet" stands one of Broodthaers's potted houseplants. The sand is not glued to the floor, and this work is so difficult to make (you can imagine what spray paint can do to loose sand) that there is only one technician in the world who is permitted to recreate it; it takes him a week. As precise as it is pointless—expensive to produce yet made of the cheapest materials, a combination of printing and gardening—Sand Carpet is a mass of daft contradictions.
But Broodthaers was not simply a master of the daft. He led the Dadaists' "nonsense" use of words and letters back towards reason. His conception of the alphabet as a set of abstract shapes derives from semiotics, the separation of signifier and signified, and from the French modernist poet Mallarmé, who was the first to make the arrangements and spacing of his words across the page part of the poem. In another well-known semiotic image, Broodthaers produced a "scientific" poster using old 19th-century illustrations of breeds of cows—but under each cow he wrote the name of a brand of car. Along with the philosophising came the political criticism. Broodthaers captured Belgium's obliviousness to its colonial crimes—millions of Africans died in Belgian rubber plantations in the Congo—in a series of sarcastic installations that combined suburban household items with symbols of war. Typical of these was "Décor: A Conquest," the inaugural exhibition at the ICA in 1975, in which a set of patio summer furniture—plastic table, chairs and parasol—stood between two shelves of Kalashnikovs, pointing upwards, as if in salute. In other exhibitions, Broodthaers dotted tropical house plants around the gallery or hung concave mirrors with gilt frames surmounted by imperial eagles, in which the walls of the art gallery were reflected—deliberately casual symbols of empire.
But perhaps Broodthaers's greatest contribution was his development of Dada's critique of the economics of art. In 1975 he wrote: "I doubt… that it is possible to give a serious definition of art unless we examine the question in terms of one constant—namely the transformation of art into merchandise… In our time, this process has accelerated to a point where artistic and commercial values are superimposed." He was highly suspicious of pop art, which he saw as an uncritical celebration of capitalism. Where Warhol made screen prints of dollar bills, Broodthaers produced a print consisting of rows of identical images of gold bars, under each of which was the name of a different artist. Thus, in the 1970s, Broodthaers pioneered revulsion at the amount of money that was spent on art, predicting the situation we now find ourselves in. In future years, when the art world comes to its senses and admits that Warhol paintings, far from being worth $70m, $20m or even $2m, are merely the devotional objects of a narcissistic age, Broodthaers may come to be seen not only as one of the late 20th century's most entertaingly arcane artists, but also its wisest.