They make the near-impossible look easy, these two, and if you have doubts then try it yourself. Select, from all the teeming materiality of the world around you, one or two elements: things that are right in front of everyone’s eyes, but near-invisible in their familiarity. Now recode your selection as art, but lightly, in a way that keeps the realness intact and – the trickier bit – makes it bloom ideationally. What you’ve focused on must remain what it is but also point, synecdoche-like, towards the systems and inequalities that surround it, at the arrant adjudicating-from-above of what matters, what has value or doesn’t. Relatedly, it should place itself in smart conversation with the fluctuant state of art. It should sing in a minor key while feeling extremely major.

Done right, that’s wizardry. So yes, it makes sense that David Hammons and Jannis Kounellis were friends: born seven years and 8,000 kilometres apart, they first met properly in 1993 at the American Academy in Rome, exhibited there together, stayed close afterwards.¹ Even leaving aside the mutated Arte Povera DNA within Hammons’s art, game will recognise game; and the oeuvres of both artists testify to their understanding that art is the most serious of games, one with only a tiny number of meaningful moves at any time.

Case in point. In 1958, when the Greek-born Kounellis was in his mid-twenties and had recently relocated to Rome, he began the ‘Alfabeto’ (Alphabet) series of paintings he’d develop until the mid-1960s. What he saw on the city streets – at a hinge moment when there was a growing exhaustion with the hermetic navel-gazing of Abstract Expressionism and Art Informel but hardly anyone seemed to know where to go next – was signage, official language, the visual traces of a cultural order. At the time, Italy was in the throes of its postwar economic miracle, which depended on something like an ordered and functional society, of which signs – go this way, go that way, do this, you can’t do that, serve the polis – are the spoor. But ‘postwar’, as the existentialists had already diagnosed, also brought with it a sense of the loss of meaning, and orders were the language of fascism. Commingled feelings about all of this feel to come complexly together, rubbing and making sparks, in the language- and order-breaking, signal-jamming ‘Alfabeto’ paintings and drawings.

In Untitled (1959), Kounellis’s stencilled letters have the authority of language-as-system and the impersonality of stencilling – suggestive of the armed forces – but vital letters appear to be missing and sense is in freefall, headed towards rhythm-driven concrete poetry, towards stranded vowel and consonant sounds, or rewinding to Dada’s epistemic revolts. By Untitled (1961), Kounellis had incorporated the wordless but meaningful glyphs of traffic signs: as well as reversing a couple of J’s so that they look like L’s, he sends a railroad line of black and an arrow sliding out of the right-hand edge. Where next, the painting murmurs – of society, of art – while refusing to accept the imposed state of things as they are, overlaying them with the anomie and suspension du jour. This is a lot to achieve by messing with letters and arrows.

Cut to later that decade, when David Hammons was in Los Angeles asking himself similar questions concerning how life’s brutalities could show up in art, could commingle with the articulately artful. The body-print works he began in the late 1960s, which counterpoint the undeniable indexical evidence of Black bodies with other elements (human hair, wallpaper, coloured paper, supports such as doors, windows, Plexiglas), were in partial dialogue with the European avant-garde – most obviously Yves Klein’s 1960s ‘Anthropometries’, using women’s bodies and blue paint. But they were also influenced by, or in a lineage with, the assemblage/collage practices of Los Angeles artists such as Noah Purifoy and Betye Saar. These works, like Kounellis’s mangled alphabets, are the thing-in-itself – the insistent trace of the real – plus what that thing might expansively signify when powered by extremely economical yet culturally loaded visual language.

Hammons, twisting an existing format towards an African American vernacular, didn’t use paint here but the pointedly ‘lower’, survival-level material of grease or margarine. (It’s arguable, too, that choosing paper over canvas, often commercial paper, was a way of pointing towards materials deemed as lesser.) For Spade (1974), he slathered his face with fats and pressed it onto paper, creating an ugly distortion of his features that he subsequently framed – and/or constrained himself within – within the shape of a spade, shorthand for the racist epithet (derived, in turn, from the phrase ‘Black as the ace of spades’). The result at once chides avant-gardism for excluding the reality of the Black experience, rides on it, one-ups it in affect. Other body prints found Hammons flexibly exploring the body under duress: it becomes a knotty abstraction (Untitled, c.1974), or an Easter Island totem that seems to be fading out (Untitled, 1977). Paint, that signifier of ‘fine’ art, turned into grease, a vehicle or waste product of food; a shifting of terms towards hard realism, perhaps not so unlike expressivity replaced with stencilling, like the finessed painterly gesture replaced with the dully authoritative word, the word then made to stutter. Here were the values, seemingly, of yesterday’s artworld mocked by someone living in today, in tomorrow.

Parallel paths, then. Hammons and Kounellis, in their careers’ respective early stages, would both establish themselves with a stylistic signature, then arrive at an impasse. Kounellis, by the mid-to-late 60s, wanted to avoid lapsing into aestheticisation, the making of recognisable objects. Hammons, in the 70s, found himself first seduced by an art market and museum sector that briefly made a cultural vogue of Black Power, and then abandoned, ghettoised, by said market a few years later. Both artists found ways out; in retrospect, those ways are comparable.

In Kounellis’s case, filtering the world through the prism of painting was no longer enough, and he began bringing natural elements into the gallery – roses, cacti, earth, minerals, live animals (birds, horses). Notable, though, is how he presented such elements. Untitled (1968), which dates from the year when Arte Povera began to be codified, is a ring of coal sacks with a thick circular abyss of the burnable material within it. Coal, here, is a reminder of the reality behind a façade: the invisible energetic material and the invisible labour of mining it that the genteel world doesn’t want to deal with. It’s also presented in an extremely structured and rhythmic way; it’s not a readymade but a system pointing to larger dominant systems, including the artworld itself and the fossil fuels undergirding it. If coal is a weird thing to bring into a gallery, even post-readymade, that points to the system’s forever deciding what’s in and out, what’s acceptable in a gallery and what isn’t. That counterpointing – undervalued things brought in from outside, wheedled into structure and visibility by the artist via an industrialised aesthetic – placed on shelves, pinned up by girders, mounted on steel backdrops – would persist throughout Kounellis’s career, as he pursued display strategies that never allowed his work to become ‘merely’ art; that always had at least one eye on the world outside.

Hammons, in a more extremist move, spent years mostly refusing the gallery system altogether, relocating to New York and making objects and interventions on local thoroughfares in the historically Black community of Harlem – selling snowballs, urinating on Richard Serra sculptures, pursuing a specific, non-artworld audience, talking in codes. His works reappropriated street detritus, street language. Untitled (c.1990) feels like a phantasmal, economical self-portrait, rubber and plastic bags wrapped around a coat rack, toting a paper bag and topped with a found hat; Fly Jar (1999) packs three meanings of fly (insect, zipper, exclusionary Black slang for stylish and cool) and a sense of unwilling containment into its tight formal parameters. Later, though, Hammons decided that the gallery system, and the wider structure of expensive goods, was itself fair game; if, that is, he could meet it on his tricky terms.

He made a series of incursions into commercial spaces in the 2000s, increasingly using abstraction – Kounellis’s old nemesis, now something of a bougie signifier – as a foil. Untitled (2009), part of a longer-running series, summons pretty clouds of grey from street-level activity: Hammons let it be known that he’d bounced a basketball caked in Harlem dirt against the sheet of paper. A suitcase stashed behind this framed, propped work suggested he wasn’t staying in the gallery long. Untitled (2013) meanwhile speaks the languages of both Art Informel and colour-field abstraction, but does so through raggedy coloured tarps that conceal a prettier-looking canvas underneath, one we’re not permitted to see. Some of this is racially coded, some of it is more largely about exclusion, and how you win from underneath. Hammons has longstanding beef with the high-end artworld, for sure, but he’s also decided that walking away from it isn’t as productive as using it.

On that note, recognise that while the works in this exhibition span a half-century and change, they are the opposite of dated. The dirty power of coal – and everything attached to it, from energy crises and wars to ecological damage – remains a live issue. Racism, societies of control, inequality: all dispiritingly relevant concerns, handled here with coiled anger, grace, smarts. And the essential shared formal manoeuvre that Hammons and Kounellis have executed, over and again in new ways, still resonates across the decades. Look, they say, you in here with your fancy canvases and fabricated sculptures and in-jokes and whatnot, see what you missed out there. I got this off the street, or thereabouts, and I didn’t even do much to it, just a few things, but the right ones. That’s my eye, that’s my art. And look – it’s so much better than yours.