For a time in the 1960s, anyone interesting who visited Warhol’s Factory would be invited to sit for a screen test: Starting in 1964, he made more than 500, of which, so far, 277 have been preserved. The Factory camera (not necessarily operated by Warhol) would record the subject on a single unedited one-hundred-foot 16 mm silent cartridge. The tests were shot at sound speed (twenty-four frames per second), but Warhol wanted them projected at silent speed (sixteen frames per second), so they take longer to see than they did to make: They retard time. (The viewing duration of each is four and a half minutes.) The sitter was often instructed not to move. Most disobeyed. Each test performs an identical protest against career and futurity: Not a prelude to a later performance in a “real” film, the test is (in most cases) the event itself, a warm-up for nothing. The screen tests, in toto, are among Warhol’s greatest works of conceptual or minimalist art (I use these terms loosely). They radiate double and triple meanings, however unintended by Warhol, who was only partially their maker.

Fashioned during one of the protracted cold war’s wary phases, the screen tests are oblique commentaries on what Avital Ronell has called, in another context, the “rhetoric of testing”: Parodies of nuclear-defense tests, Warhol’s screen tests interrogate what it means to be a good, tractable, visible citizen. They also investigate thematics of school tests (which Warhol sometimes failed); send-ups of final exams or pop quizzes, Warhol’s screen tests transvalue failure’s nausea into the giddiness of unadulterated, motiveless, lightly sexualized gazing. Watching the screen tests, we’re being tested: Will we, the viewers, comprehend what we see, or will we scoff, walk away, give up this chance for vision?

For this excellent, timely MoMA exhibition, curated by Mary Lea Bandy, twenty-eight of Warhol’s screen tests were transferred to DVD and shown in looped clusters of three or four, on six different-size video monitors surrounded by wooden picture frames, plus one screen on which a DVD is projected. Be grateful for DVD’s ease, but regret what’s lost—the movie projector’s plaintive noise; celluloid’s luminescence and nuance; film’s pocked, cloddish corporeality.

Poet Gerard Malanga in a screen test tries to stay immobile, but he finally swallows: Adam’s apple pushes against turtleneck. Garbo talks, Gerard swallows. Meanwhile, on an adjacent video monitor, superstar “Baby” Jane Holzer slowly brushes her teeth. White toothpaste foam echoes her pale hair, the significant, storied bouffant of 1964’s It Girl, a coif sublime and disordered, the regalia of a de facto aristocrat eager to get up on the wrong side of the bed. Jane cheerfully plays the Warhol torture game: She spits out toothpaste and laughs, apologetic, as if she knew that to demonstrate ordinary need (I’ve got to spit out my Crest, lest I gag or choke) constitutes failure. (To pass the test, you need to be a machine, though it’s not clear whether passing the test is a desirable “outcome,” as psychologists used to say.) The toothbrush serves as paintbrush; Jane is nearly making a painting—in her mouth. Finally, the reel-end leader—a white strip of unexposed film—overwhelms her. (Warhol never omits the leader: Blankness excited him.) Because, in this case, the leader’s pallor matches Jane’s toothpaste, it seems as if some remorseless, hygienic tide were overtaking her vulnerable, finite ritual.

Dennis Hopper in a screen test moves his head to the beat of a music the silent film can’t include. He’s showing off Hollywood power: He’s not just an ersatz god, like the other victims. Inevitably a viewer compares various star voltages—Dennis versus Gerard versus Donyale. Donyale Luna, model and actress, wins; in an overwhelmingly white Factory, she is an exception, an African-American beauty, who, in her test, is pure diva, presenting a delicious, mobile excess of mannerism. With repeated, refined gestures, she fixes her hair, as if assessing herself in a mirror, and that gesture (primping for a role that may never come to pass) means victory in the screen test’s world of simulacral stardom. With a painted-white fingernail, Donyale checks for unseen flecks of stray mascara; she sinks below the frame’s horizon but then bobs to the surface, rescued, her eyeliner queenly as before. Finally, when the leader returns, she, like the others, gets whited out. The leader is the exit ramp away from representation, from being-known; this surrender to erasure is always the most orgasmic—and annihilating—moment in a Warhol film. When the leader whites out the subject’s image, there is no panic, no loss; Warhol avoids the castration of the “cut” by re-valorizing sudden endings, investing them with magic. The prison cell of personality, happily, shuts off. Every penance eventually ceases. However, for some subjects (such as Donyale), this moment of final erasure poignantly recapitulates history’s indifference. Careful spectatorship seems a temporary antidote to amnesia.

Not overtly erotic, the screen tests nonetheless speak sexuality, just as tele- phone books or actuarial tables do; any artifact numbingly antithetical to physical pleasure articulates the space for a prurient counterreaction. Because, watching screen tests, we are postponing our own bodily delights, these films express the divide between vision and other physical processes (such as sucking and speaking). The screen tests may be silent, but they are obsessively oral. Each subject must engage or ignore the mouth. Poet-filmmaker Piero Heliczer smokes. (A plume of shadow falls over his face: In Warhol’s ostensibly deracinated system, a shadow’s silent arrival is momentous.) In a second screen test of “Baby” Jane, she chews a stick of gum: The wrapper, briefly visible, seems to identify it as Wrigley’s Doublemint. Like a sexual athlete, she removes the foil adroitly with mouth alone and then chews the revealed stick methodically, using blow-job gestures—like drag-queen Mario Montez fellating a banana in a contemporaneous Warhol film. Jane has the Bardot-caliber comedic flair to send up sexuality rather than simply undergo it. (Note: Jane’s fingernails are not as opulent as Donyale’s.)

The screen tests test the subject’s emotional immunity. Ann Buchanan, in her screen test, is crying. Because I don’t know who she is? Because Warhol humiliated her? And yet her tears seem unemotional, Nico-esque. Pain, in Warhol’s work, is sourceless; one is never sure who caused it or whether the person supposedly experiencing it (in this case, Ann) is fully aware of her suffering. Warhol gives us pain without awareness: Ann’s test sells anesthesia.

James Rosenquist, artist, needn’t obey the imperative to sit still, so he spins in his seat and becomes a merry-go-round. Warhol provokes motion sickness: This test I can’t watch. As Rosenquist rebelled by spinning, so poet Harry Fainlight, who resembles Paul Auster, disobeys by standing up, in the middle of his test, and walking away, revealing the wall behind him; screen-tested, the wall qualifies as an abstract painting. When Fainlight returns to duty, he casts a shadow. For Warhol, a shadow counts as facture, as “expressivity” itself; and a wall is often made to seem as compelling—as open to dialogue—as the person posing in front of it.

Democratic Andy’s screen tests pronounce equality. Gerard Malanga = Dennis Hopper. Donyale Luna = James Rosenquist. Warhol can’t sidestep actual differences, however, so he reinterprets equality as equivalence. X isn’t equal to y, but x and y contain Baudelarian correspondences; if x and y occupy identical boxes, then we are free to dream that they are twins, even if x is a somebody and y a nobody. Warhol translates equality from politics into metaphor: Equality becomes not civil liberties but the endless, arbitrary, orgiastic play of substitutions. If two people are framed identically, then we are allowed to tease out equivalences—symbolic affiliations—between them. Thus Warhol proves himself a tropological master and tests our own tropic tendencies. He allows us to exercise our analogy-seeking capabilities to the full; he suggests that every individual is an arena for likenesses to germinate. The screen tests permit as promiscuous a field as possible for these similarities to reverberate, but toward no liberatory end; they merely oscillate, an optical effect, a mirage.

These screen tests are not aptitude tests but existence tests: Are you visible? If the answer is yes, what are your visibility’s secret toxicities? Whom does your spectacle hurt? Given appearance’s lethal nature, the preferred goal may be disappearance, or disguising yourself as nothing. The screen tests permit but also punish individuality; and the copresence of anarchic and carceral vibes is an American conundrum that Warhol fastidiously chronicled. Warhol points out celebrity’s paradox: Is the star a punished or a privileged site? Is notoriety—being-known, being-seen—torture or delight?

Warhol is (if you wish him to be) a minimalist, whose morphemes are not shapes or colors but personalities. A face is interesting, but so is the time we spend looking at it. Seeing a Warhol screen test, we compose a conceptual sculpture: an empty box, containing our time-of-beholding. Face equals duration: Warhol leaves us contemplating formal equations that contain more gaiety than we could ever guess.

Wayne Koestenbaum is professor of English at the City University of New York’s Graduate Center and the author of Andy Warhol.