A tale of three exhibitions: assemblages, squares, lyric oils. Collages at Guggenheim; Stamos retrospective; Josef Albers centennial

Collage attained legitimacy as an art form one day in May 1912, when Picasso glued a strip of oilcloth printed with simulated chair caning onto the surface of a painting. He thereby altered traditional pictorial space by creating visual tension between the physical surface of the work and its illusionistic depth.

Intrigued by the idea, Braque, shortly thereafter, made his first papier coll'e (pasted paper works) by gluing simulated wood-graining to the surface of a drawing.

By the end of 1912, both artists had begun to attach wallpaper, newspaper clippings, ticket stubs, and other unorthodox materials to painted and drawn images.

These were followed by Picasso's now-famous maquette for ``Guitar,'' which he constructed, Cubist fashion, out of flat cardboard forms, and by Marcel Duchamp's first ``Readymade,'' a sculpture produced by attaching a bicycle wheel to the top of a kitchen stool.

Since then, 20th-century art has been enriched, not only by two-dimensional collages and three-dimensional assemblages, but also by the utilization of ``found objects,'' items picked up almost anywhere, and exhibited as art with little if any alteration.

Roughly 150 works representing these three categories have been brought together at the Guggenheim Museum by Diane Waldman to form a fascinating account of how modernism has benefited from the collages and assemblages of such artists as Schwitters, Calder, Rauschenberg, Johns, and Kiefer.

Major examples tracing the evolution of these art forms from Cubism through Pop Art and into the present rub shoulders with less dramatic but no less important pieces by the Constructivists, the Berlin Dadaists, and the later Surrealists.

Klee is particularly well represented by his delightful ``Aging Venus,'' as are Archipenko by ``Medrano II,'' Grosz by ``The Engineer Heartfield,'' and Cucchi by his powerful ``Untitled'' (1986).

It is Anselm Kiefer, however, who steals the show with his darkly mysterious ``Seraphim'' of 1983-84. At almost 11 feet in height and a little over 10 feet in width, it may be one of his ``smaller'' paintings, but it is also one of his best. No one else working today can say and suggest so much with so little - and with so much natural elegance and grace.

At the Guggenheim Museum through May 22. Stamos keeps getting better

Theodoros Stamos, the youngest of the original Abstract Expressionists, has been painting for considerably more than four decades, and he keeps getting better all the time.

His exhibition at the Kouros Gallery here contains several of his finest pictures to date, including ``Infinity Field Jerusalem III'' and ``Infinity Field Torino IV,'' both of which project an aura of poetic and painterly sensibility that is almost heartbreaking in its ability to convey something of both the beauty and the pain of human vulnerability to the deeper and more mysterious dimensions of human reality. In them, and in two or three others, Stamos moves beyond even the most effective of his earlier canvases to affirm once again his position as one of today's best lyric painters.

At the Kouros Gallery, 23 East 73rd Street, through April 23. Albers centennial observed

Josef Albers (1888-1976) is most famous for three things: his many years as a teacher of art at the Bauhaus, Black Mountain College, and Yale University; his influential method of teaching color; and his strikingly simple abstract paintings known collectively as ``Homage to the Square.''

Together, they pushed him into art-world prominence and made him a major influence on several generations of European and American artists, architects, and designers.

In celebration of the 100th anniversary of his birth, the Guggenheim Museum has mounted the first major retrospective of his work.

Its 247 paintings, works on paper, glass assemblages and constructions, furniture, photographs, and photo-collages were drawn from public and private collections in Europe and the United States, and were assembled by Nicholas Fox Weber, executive director of the Josef Albers Foundation.

As is to be expected, color plays a dominant role in this exhibition, from the glass assemblages executed in 1921, through the ``Etudes'' and ``Improvisations'' of the mid-1930s; the small geometric oils on Masonite (especially, ``To Mitla'') of 1940; the numerous ``Varients'' of 1948-53; to the ``Homage to the Square'' series that occupied him for the last quarter-century of his life.

Of particular interest are roughly three dozen early sketches and drawings, most of them very quickly dashed off and quite brilliant in their evocation of character and action, whose existence he kept secret throughout his career.

``Self-Portrait III'' is especially noteworthy, since its precise, angular structuring prefigures his later interest in geometric abstraction.

At the Guggenheim Museum through May 29. The show then travels to the Staatliche Kunsthalle, Baden Baden (June 12-July 24), and the Bauhaus-Archiv, West Berlin (Aug. 10-Oct. 4).