William T. Williams, 'Elbert Jackson L.A.M.F. Part II' (1969), on view in 'What Is Painting?' at the Museum of Modern Art.

The delightful proposition of "What Is Painting?" — a broad survey of art from the 1960s to today, drawn from the Museum of Modern Art's contemporary collection — is that we have utterly lost our way: We no longer have any idea what painting is, and we are much better for it. Loosely chronological and with an equally relaxed thematic structure, the show makes its argument largely through the variety and quality of the work on view.

A single canvas by Peter Doig, "Pink Snow" (1991), stands just outside the galleries, introducing the show and demonstrating how exuberantly powerful contemporary painting can be, despite its identity crisis. A Klimt-inspired, faintly expressionist take on a winter scene, it depicts an orange-faced skier on red skis standing before a large house in a storm of snow that is white but also red, green, yellow, orange, and black.

Vija Celmins Gun with Hand #1 (1964), 24 1/2 x 34 1/2", on view in 'What Is Painting?' at the Museum of Modern Art.

The first gallery lingers on the representational, bringing together a handful of what are undeniably paintings, by some influential artists whose work doesn't fit elsewhere. A wonderfully understated Vija Celmins painting from 1964 depicts a hand firing a revolver, a motif one would not be surprised to discover in more recent works by Luc Tuymans or Wilhelm Sasnal, each of whom are represented here. Similarly, the cartoon style of Philip Guston's "Head" (1977), with its elaborate sutures lacing up a pink cranium, infects numerous artists today. Certainly "Ship" (1997Ð99), a piece by Carroll Dunham found several rooms away, would be unthinkable without Guston's example.

Philip Pearlstein's rigorously perceptual brand of realism, here exemplified by the rather dour nude "Two Female Models in the Studio" (1967), has been largely influential to less stylistically affronting artists than those included in the exhibition. Still, the ripples of his influence extend, if faintly, out to Chuck Close, John Currin, and Pearlstein's old friend Andy Warhol.

After a gallery that groups together '60s-era abstract influences on contemporary work, painting's center begins to disintegrate rapidly. In a room focusing on painting as an idea rather than a practice, John Baldessari's "What Is Painting" (1966Ð68) — which gives the show its title — presents nothing more than a text, painted, that ends with the coolly ironic statement: "Art is a creation for the eye and can only be hinted at with words." Baldessari's canvas is guarded by other genre-bending efforts, a Barbara Kruger Photostat using a detail from Michelangelo's Sistine Chapel ceiling, and an embroidered "painting," "Sampler (Starting Over)" (1996), by Elaine Reichek.

	Lee Bontecou Untitled, 1961, 8 1/4" x 7' 5" x 34 3/4", on view in 'What Is Painting?' at the Museum of Modern Art.

A nearby room extends the ground even farther outside the frame, into three dimensions. While the wall cannot contain Lee Bontecou's abyss, a wall sculpture from 1961, in which welded steel, canvas, and black fabric jut out at the viewer and recede into blackness, Jackie Winsor's "Bound Square" (1972), an empty wood and twine frame resting on the floor, contains nothing but wall.

Such fecund pairings flower abundantly throughout the show. The squeegeed blurriness of Gerhard Richter's photo-based oil "Court Chapel, Dresden" (2000) — a self-portrait with a friend — seems at first to contrast with the precise photorealism of Mr. Close's portrait "Robert/104,072" (1973Ð74). The nearer one gets to the Close, the fuzzier it becomes, and the farther one gets from the Richter, the more it resolves into focus.

In places, figuring out the relationships between the works is half the fun. Repetition seems to unite Andy Warhol's multiple portrait of "Lita Curtain Star" (1968); Allan McCollum's "Collection of Forty Plaster Surrogates" (1982Ð84), a group of framed black rectangles of various sizes; Sherrie Levine's "Large Check" (1987) series of multicolored checkerboard paintings, and Richard Pettibone's hilarious set of 10 tiny, though faithful, replicas of Frank Stella's "Protractor Series" of paintings.

Richard Pettibone Frank Stella, "Sabra I," 1967 (1968). Synthetic polymer paint on canvas, 6 3/16 x 6 3/16 x 1/2", on view in 'What Is Painting?' at the Museum of Modern Art.

The history of white as a minimalist lodestar includes a 1981 Agnes Martin canvas constructed of faint bands of salmon, blue, and eggshell white as well as Robert Ryman's "Attendant" (1984), where the metal wall fasteners upstage the white painting. It concludes with "Presence" (2000), an extraordinarily delicate silverpoint web, afloat in a large field of white, by Shirazeh Houshiary.

Text paintings, German Neo-Expressionism, and Pop-inspired wackiness all receive their due here (though not, sadly, black paintings). By the time one reaches the last two galleries, a certain symmetry has been achieved: The penultimate gallery yokes together current representational styles and the final gallery current abstract works. Fittingly, one of the very last works one encounters, a 2006 untitled study of Xs by Wade Guyton, was made, not with paint, but with an ink-jet printer and canvas.

Does the use of a printer mean its product is a print, a printout, or something else? Of course, the answer depends on definitions: In other words, What is a painting? This fine exhibition insouciantly suggests a painting is not what we are used to, not what we expect, but rather, whatever we can get away with.