The distinguished Catalan artist Antoni Tàpies, who has died aged 88, conceived of his work as a form of meditation on "the void" – more specifically, "that play of emptiness and fullness which composes everything and which reveals the meaning of nature". He expressed this esoteric philosophy, partly inspired by Zen Buddhism, through a multiplicity of potent, often paradoxical, objects.
In his "matter paintings", Tàpies mixed pigment and varnish with unconventional materials, including marble dust and sand, to create dense, wall-like surfaces that are both blank and teasingly mysterious. He also frequently included cruciform shapes that look less like Christian symbols than negative marks on a child's exercise book, the signatures of illiterate people, or even distortions of the artist's own initial. Clearly he relished the ambiguity.
Tàpies's achievement was to create highly intuitive, enigmatic images that have the potential to change our perception of reality, but defy reduction into a few lines of analysis. But then he was never working with his obituarist in mind. One of his earliest collages, from 1946-47, consisted of a cross made from paper torn out of a Catholic journal's obituaries page. He obviously did not have much respect for the genre.
Despite this elusiveness, it is still possible to outline a variety of themes and influences: leftwing politics and humanitarianism; the practices of Zen meditation, in which contemplation of a wall or a garden of sand can lead to enlightenment; the Christian concept of incarnation; and a conviction that art was a kind of alchemy or magic that could transform the basest materials. While some of these qualities can be traced to aspects of Tàpies's early life, the precise path that he took still has the potential to surprise and bewilder.
Born in Barcelona, Tàpies came from the Catalan intellectual elite. His father, Josep Tàpies i Mestres, was a lawyer with secular, nationalist sympathies who worked for the republican Catalan government during the Spanish civil war of 1936-39. In contrast, his mother, María Puig i Guerra, was a devout Catholic, the daughter of a prominent rightwing separatist, who insisted on a religious education for her son throughout the upheavals of the period.
Tàpies's schooling did not have quite the desired effect. Apart from gaining a fear of nuns, he developed an idiosyncratic spirituality that was to influence his later work, although not in ways that were appreciated by the church. Even more important were the two years that he spent recovering from a lung infection contracted in 1940. During this period, he made copies of Van Gogh and Picasso, and read Dostoevsky, Ibsen, Schopenhauer and Nietzsche, as well as the Japanese Buddhist Okakura Kakuzo – a varied list that weaned him from the conventional classicism admired by many older Catalan artists.
Compelled by his father to begin a law degree, in 1944 Tàpies also attended a drawing course at the Academia Valls in Barcelona, where his artistic aspirations were encouraged by the poet and critic Josep M Junoy. He spent the 1940s developing an idiom that was inspired partly by the "primitive" art of children and, more obviously, by Paul Klee and the surrealists. At times, he used Max Ernst's grattage (or scraping) technique, and he was also influenced by his friend Joan Miró, whom he met in 1948. In the same year, Tàpies co-founded the avant-garde Dau al Set group with, among others, the surrealist poet Joan Brossa.
Many of Tàpies's early drawings and paintings were self-portraits, which varied significantly in the liberties they took with his actual features. By 1946, however, he was already using one of the motifs that would become familiar: he began to create collages with crosses, using not just newsprint but scraps of toilet paper.
Tàpies's development was stimulated in 1950-51 by a French government scholarship to Paris, where he had a memorable encounter with Picasso and also briefly became interested in social realism. Despite these experiences, Tàpies was swiftly drawn to the lyrical abstraction known as art informel, especially after 1953, when he experienced the American equivalent, abstract expressionism, at the time of his first one-man show in New York.
This exciting period culminated in 1954 with Tàpies's marriage to Teresa Barba i Fàbregas, whom he had known since she was 16. The couple had a flourishing family life, much of it conducted at their country house in Campins, about 50km from Barcelona, which they acquired in 1960.
While Tàpies's exhilarating new style of "gashes, blows [and] scars" was undoubtedly very successful, eventually it evolved into something more serene and profound: "One day I tried to arrive at silence … Those millions of furious clawings were transformed into millions of grains of dust, of sand … A whole new landscape, as in the story of one who goes through the looking glass, opened before me as if to communicate the most secret innerness of things … And the most sensational surprise was to discover one day, suddenly, that my paintings, for the first time in history, had turned into walls."
As the artist's name means "walls" in Catalan, his adoption of this theme might seem particularly apposite. Yet in one of his most stimulating essays, Tàpies has associated this subject with such a range of contradictory experiences – from "separation, cloistering" and "the romantic prestige of ruins" to "quartered bodies" and "reflections for contemplation of the earth" – that its significance is anything but neat.
Nonetheless, all his "walls" and related imagery share one quality: a suggestion of something that lies beyond the material world but is only sensed in its absence. This point is made particularly clear in Spanish Arch (1961), with its elegant, blocked opening, but is implicit in much of his oeuvre, from the mysterious Metal Shutter and Violin (1956), one of his earliest assemblages, to the esoteric markings of Writing on the Walls (1971).
Furniture, whether real or represented, also became a key component of Tàpies's work. The bed took on a particular significance as an archetype connected with the beginning and end of life, a place of erotic excitement, warmth and death. Tàpies's vivacious handling of his materials was never more brilliant than in the crisp creases of Sheet Knotted with String (1971), while Rinzen (Awakening, 1993) incorporated an overturned hospital bed in a chilling installation at the Venice Biennale, partly made in response to the war in the former Yugoslavia.
Although much of Tàpies's art deals with universal issues, he never ignored his lifelong goals of democracy, social justice and self-determination for Catalonia. In The Catalan Spirit (1971) the red and yellow of the national flag are accompanied by frenetic, political graffiti, whereas Companys (1974) refers to the republican leader, Lluís Companys, who was executed by Franco in 1940. Both works are dominated by vivid, sanguinary stripes or splashes, while Roman Painting and Cap of 1971 includes a Catalan peasant's scarlet hat, suspended from a rope.
Tàpies did not confine his activism to his art. In 1966, he was detained and fined for attending a clandestine political meeting, and towards the end of Franco's regime he was involved in high-profile protests against the death penalty, for which he designed an unforgettable lithograph and screen-prints.
After the dictator died in 1975, Tàpies produced thoughtful and influential analyses of the role of "cultural workers" during that uncertain period. Soon afterwards, in 1978, he was able to publish his autobiography, Memòria Personal, which he had been writing for more than a decade.
Spain's return to democracy created significant new artistic opportunities. In 1983, for example, he completed a public monument to Picasso in Barcelona. Most importantly, in the following year he set up his own foundation, theFundació Antoni Tàpies, which moved in 1990 to a spectacular Modernista building in the city's Eixample district. As well as housing Tàpies's donations of his own work, this institution has an exhibition venue of international stature. It was here, on the occasion of the foundation's remodelling, that Tàpies made his last public appearance a year and a half ago.
In his later years, Tàpies's art remained as subtle and diverse as ever. He felt no need to divide his career into neat, marketable phases, but continued to experiment with a range of imagery and media. His figurative work included sculptures in terracotta, bronze and even repoussé metal, as in the eerie Metallic Profile of 1993. In 2000 he contributed to Encounters: New Art from Old, a group exhibition at the National Gallery in London that offered radical responses to the old masters. His offering was a characteristically earthy painting of the female body, giving particular emphasis to parts, such as the soles of the feet, that are usually ignored or even despised.
Above all, in such pieces as Homage to Matter (2006) he developed his essential themes: the spirituality of the material world, and the infinite value and mystery inherent in even the most humble things.
Two years ago he was given the hereditary title of Marqués de Tàpies by King Juan Carlos. He is survived by Teresa, and their children Toni, Clara and Miquel.
• Antoni Tàpies Puig, Marquess of Tàpies, artist, born 13 December 1923; died 6 February 2012