Turning the corner and suddenly coming into its space, I had the sensation of meeting an old friend. It is, in fact, the least impressive of the four Robert Smithson pieces on display at Dia:Beacon, Dia’s factory-sized museum located just off the Hudson River in southern Duchess County, New York. Gravel Mirrors with Cracks and Dust consists of a dozen mirrors roughly a one yard square each. Half of these are laid side-by-side on the floor right at the edge of the gallery wall, with the remaining six are fixed to the wall right at ground level, so that without anything else being present, it might appear to be some sort of mirrored hinge. However, atop each of the six mirrors on the floor is a small mound of gravel.

I had first met this work, one of Smithson’s Site/Nonsite series, decades ago at a retrospective of the late earthwork artist at the University of California Art Museum in Berkeley. It looked every bit as humble there as it does here. You have to actually sit on the concrete floor to really get a decent view of the thing, otherwise you might not notice it at all, save to check out the reflection of your shoes from its mirrors. Many of Smithson’s indoor works make use of some combination of earth, variously defined, and mirrors. Such is the case, sort of, at Dia.

Leaning Mirror, which was created in 1969, the year after Gravel Mirrors, consists of a large mirror, maybe six feet square, jutting out of a mound of dirt at something like a 60º angle. It looks, in a sense like a wing, or perhaps a crash (anticipating, ironically, the sense of jutting from Ant Farm’s iconic Cadillac Ranch).

Closed Mirror Square (Cayuga Salt Mine Project) consists of a mirrored box – with a clear glass roof – set into a mound of rock salt from the Cargill mine in Pennsylvania.

Depending on your height, you can see a part of your reflection inverted & reflected on the walls of the interior box.

Map of Broken Glass differs from the other three projects only insofar as the “mirror” has morphed into glass and is the material being used in a gravel like mound itself, everything from large shards to relatively small slivers (although, I should note, the glass itself is fairly thick, what I would think of as an “industrial window” grade – the barefoot viewer is less apt to get glass in one’s feet than they are to deal with flecks of dirt from Leaning Mirror or rock salt from Closed Mirror Square, both of which had specks starting to travel along the gallery floor).

In the Dia:Beacon galleries, this is the piece that looks spectacular, although I must say that it doesn’t really need to in order to create its impact.

Peter Schjeldahl, trying to prod me a little, once asked me if I didn’t think that the only serious thinking in the arts “these days” (this was the mid-1980s) occurred in the visual arts. While I understood what Peter was getting at – we’d spent the day visiting galleries & were back in his kitchen – I responded in kind, saying that I sometimes felt relieved when I saw a piece of visual work that had any ideas at all.

With Smithson, who died in his mid-30s in 1973 when a plane he was using to view the ongoing construction of Amarillo Ramp crashed, you never have any question about this at all. He is perhaps the clearest,. and deepest, thinker of any of that generation of conceptually oriented artists. And I find that I respond to his work not unlike the way I do when I’m Thomas Jefferson’s Monticello – I feel I’m viscerally in the presence of a great questing mind.

It’s interesting to have this reaction – it’s positioning within the 300,000 square-foot recesses of the converted box printing factory that is the Dia facility is off to one side and in back (not unlike the location where most bookstores hide poetry) – yet Smithson’s work resonates with more critical intelligence than much of its collection overall.

The cohesiveness of the collection is remarkable. Basically, it’s the work of major artists in abstract modes between 1960 and the present. Even an Andy Warhol, who is represented by a large sequence of paintings, virtually identical but for their various neon colors, is here unveiled as a formalist of abstractions – the core image for the sequence, entitled “Shadows,” is exactly that, a shadow impossible to project backwards to an object. Indeed, the work suggests that Warhol is as intense a thinker about the role of color as any of the abstract expressionists, possibly even more so.

But when you look at artists who lack the rigor and formal imagination of a Smithson or a Warhol – Blinky Palermo, for example, looking for all the world like the love child of Josef Albers and Ellsworth Kelly, or Dan Flavin’s fluorescent lights – all shine & no illumination – you realize what the real constraints on this generation proved to be: how to think when the palette is reduced neoformalist variations on minimal materials. If the result is good, as it is with Sol Lewitt or Donald Judd’s wonderful wooden boxes – the best work of his I’ve ever seen – it can be extremely powerful. But when it’s not, it just sits there. Fred Sandback’s string pieces, framing large rectangular spaces in “canvas-like” positions actually reiterate a project I did for a show in Seattle some 34 years ago. Seeing such a narrow concept literally spun into a career ultimately is depressing. It suggests that art is little more than identifying possible brand positions within a market economy.

I was struck by a couple of artists whose work I’d never looked at that closely before. One was Walter De Maria, whose uniform pieces, a circle & a square on the floor, in his Equal Area Series demonstrate a commitment that modest variations of a Sandback or ersatz glitz of a Flavin just doesn’t get. For some reason, I’d never realized that De Maria was born in Albany, California, my home town.

Another very-close-to-homie turns out to be Michael Heizer, born in Berkeley. Heizer has what I saw as two very disparate projects here. One is a series of geometrical shapes on the floor – Ellsworth Kelly gone to boards or whatever – that is extremely predictable. Click on the link on his name and you’ll see. But Negative Monolith #5, a gigantic – like 20 foot high – stone tightly wedged into a vertical rectangular slot in a wall is brooding and powerful. I found myself liking the fact that it doesn’t all work for him, as indeed it doesn’t for John Chamberlain. His signature piece here, The Privet (again, click that link), is a sculpture of metal that appears to have escape from a humongous shredder. It is a solid wall all its own, yet incredibly delicate, as if auto bodies could be reduced to confetti. But next to it, many of his smaller projects look like sketches, sculptural doodling.

And that’s perhaps why I like the Smithson pieces here best of all. In his brief life, Smithson made some of the most striking visual images of the past century – Spiral Jetty is a work worthy of a Duchamp in making you see the world completely differently – and yet the power of the image is never ever what the work is about. The tension in these four pieces – between smooth & rough, shiny & opaque, natural (poured) vs. cultural (square), beautiful & ugly – is simply unending. After three dozen years, they’re as powerful as ever. In some sense, perhaps even more so.

The other thing that struck me as I moved through this space was just how quickly this collection is going to seem frozen in time. For one thing, an enormous number of these visual artists are dead now: Smithson, Warhol, Palermo, Flavin, Sandback, Judd, Agnes Martin, Joseph Beuys. If you thought that MoMA seemed like a time capsule from the not-so-recent past, you won’t believe Dia:Beacon in ten years – someone like Kara Walker is going to seem like – indeed, be – a voice from a completely different century by comparison to this cool commitment to formalist abstraction encased in a museum that feigns being a loft space (serious fin de siècle nostalgia in that alone) alongside the Hudson, gently flowing.