Out in the back garden of Marian Goodman Gallery in Hollywood, a solid steel square, four feet wide and four inches thick, sits on the gravel covered ground. “Dark” is a legendary 1968 sculpture, one that caused great consternation when first shown at an annual purchase competition at Southwestern College in Chula Vista, south of San Diego, where it won the $1,900 first prize.

Adjusted for inflation, that’s more than $17,000 today — not an insignificant chunk of change for a ‘60s art contest.

Some were outraged. A blank steel plate, apparently just waiting to rust? Local sculptor Frank James Morgan, whose conventional portrait busts and stylized bronzes of women had gained some notice, wasn’t having it, and he denounced Nauman’s sculpture as “junk” in a letter to the San Diego Union. Artist John Baldessari, a competition organizer just then getting traction for his own Dada-inspired anti-art, leapt to its defense in a three-page, 18 bullet-point text.

Bruce Nauman, “Dark,” 1968; steel

(Christopher Knight/Los Angeles Times)

At Goodman, the sculpture sets up “Bruce Nauman: Pasadena Years,” a modestly scaled but museum-quality survey of his work from 1969 to 1979, the prolific decade when the now critically lauded artist lived in Los Angeles. (A resident of New Mexico since then, Nauman is 83.) Two dozen works are on view, including sculptures, installations, videotapes, drawings and prints, plus the artist’s book “LAAir,” featuring 10 full-page color photographs said to show the city’s famous smog. The book’s title makes a droll pun for “lair,” a villainous place of danger or death, while his vivid, mostly monochrome abstract photographs of poisoned atmosphere wittily recall fashionable Color Field paintings.

“Dark” immediately predated his move from Northern California. The dust-up that ensued among artists and critics was another signal that the region was continuing to mature as a center for the production and presentation of provocative new art.

“Dark” doesn’t look like much. The solid but shallow steel box, weighing in at a reported 1.3 tons, was an example of a recently emerging, stripped-down Minimalist aesthetic. The artist’s last name is written in block letters along one edge, but there’s some confusion over whether the artist or the school added it later as an identifier. There was also the matter of the sculpture’s title, “Dark,” which referred to the artist’s claim that the word had been scrawled on the underside of the brute slab.

Was the word “dark” just meant to describe what was under there — darkness, the absence of light beneath a space-gobbling hunk of immovable material? Was it inscribed as a mordant Dada riposte to the shimmering ephemerality of Light and Space art, the perceptual spatial enigmas by Robert Irwin, Doug Wheeler and others who were fashioning the first wholly original art form to emerge from sunny Southern California?

Maybe. But encountering “Dark” now, something else stands out: There is no way for a viewer to know for certain whether the word is really written on the underside, beneath all that obdurate tonnage. None. It’s unknowable. A viewer, and not just the gravel beneath the steel plate, is in the dark.

Aside from the general “don’t touch” social prohibition hovering in the presence of any art object, lifting this particular weighty slab is impossible. You’ll simply have to take the artist’s word for it that the declaration is written there. The confrontation with Nauman’s sculpture is a blunt exercise in artistic faith — an expression of trust between artist and audience, and an agreement to play together. If you can’t grant that, you probably should just walk away from art — this or any other.

Installation view of Bruce Nauman’s 1969 “Performance Corridor” at Marian Goodman Gallery

(Elon Schoenholz)

That contemporary art might be a dubious realm populated by frauds and charlatans seems quaint today, but once upon a time it was a standard assumption. It was there from the beginning. In 1916, at the first large-scale U.S. exhibition of Modern American art held in New York City, the acerbic critic at The Nation magazine gave the stink-eye to claims of the avant-garde’s artistic seriousness.

“Many persons are most seriously convinced that the world is flat,” wrote Frank Jewett Mather, looking down his nose, “the poor whites of certain Southern regions are most seriously convinced that clay is a delicious comestible. But their seriousness doesn’t matter, and I think that the seriousness of these Modernists matters very little.”

Nauman, at a tumultuous and perplexing period of upheaval politically, socially and artistically, was getting down to basics.

For 1968, which has been called “the year that shattered America,” such a compact of faith at the core of “Dark” — and a contract between strangers, no less — is no cavalier thing. Neither is it today. Civil rights, gender equality, Vietnam, student protest — so many divisive crises then are being repeated now, in our time of advancing darkness, with Ukraine and Gaza replacing Southeast Asia. Nauman’s sculpture is thoroughly non-figurative, but its inescapable social and political dimensions resonate anew.

So do those of “Performance Corridor,” a baffling installation made when Nauman moved into a Raymond Ave. studio the following year. He was 27, with a wife and son, and they shared a rambling Craftsman house nearby, owned by curator and art dealer Walter Hopps, with artist Richard Jackson. Hopps was a wealth of information about Dada godfather Marcel Duchamp, whose now legendary 1963 retrospective he had organized for the Pasadena Art Museum. Nauman paid close attention to Duchamp’s penchant for an art of puns and conundrums.

As a sculpture, “Performance Corridor” might be even more initially mute than “Dark,” but it ends up speaking volumes. The corridor, eight feet tall and 20 feet long, is built from ordinary wall board and exposed two-by-four struts. One end is flush against a gallery wall, and looking into the unembellished corridor from the open end isn’t promising. Roughly shoulder-width, it invites one person at a time to walk down the hall looking straight ahead.

Bruce Nauman, “Performance Corridor, 1969; wall board and wood

(Christopher Knight/Los Angeles Times)

Arriving at the blank gallery wall at the end of a restricted, uneventful walk, one’s immediately puzzled thought is, “Why am I here?”

And, after all, that is the question, isn’t it? The performance in “Performance Corridor” isn’t something Nauman is doing, beyond performing a set-up for any art viewer to be nudged into wondering: Why am I here?

Existential inquiry is an artistic staple, but typically it tends toward big gestures and grand declarations — see extravagant and flamboyant Abstract Expressionist paintings of the late-1940s and 1950s for examples. Nauman’s, however, is refreshingly without illusions or pretensions.

Also in 1969, although not part of the fine Goodman gallery exhibition, he sketched out a paradoxical skywriting sculpture that wasn’t executed until 40 years later, when finally, it was performed in 2019 from a small airplane flying over Pasadena’s Rose Bowl. “Leave the land alone,” the ephemeral skywriting said in puffs of wispy smoke. The aerial sentiment about environmental degradation below also artfully invokes individual human mortality, when just a slight pause precedes the final word.

Leave the land — alone. Nauman’s skywriting drifted for a moment in the late-summer breeze, then disappeared.

Marian Goodman Gallery, 1120 Seward St., Hollywood, (310) 312-8294, through April 26. Closed Sunday and Monday. www.mariangoodman.com