BY MID-1976, 54-year-old Los Angeles artist Robert

Irwin had spent more than a decade abandoning successively all the assumed conventions of painting: "figure, line, focus, permanence, and signature"--even his studio. He finally found himself "prepared to jettison . . . the very requirement of any overt activity of making (emphasis mine) as a necessary prerequisite for artistic viability." By 1977, at the time of his Whitney Museum retrospective, Irwin argued for " 'perception as the essential subject of art.' " He had reached the terminus of his trajectory. "When all the nonessentials had been stripped away, came the core assertion that aesthetic perception itself was the pure subject of art. Art existed not in objects but in a way of seeing."

In Seeing Is Forgetting the Name of the Thing One Sees Lawrence Weschler, clearly intrigued, charmed, and inspired by Irwin, has written an appreciation of the artist--a celebration, rather than a critique. In his exegesis, its title adapted from Paul Val,ery, Weschler tries to understand Irwin, his work, his ideas, essentially through the artist's own understanding of them. He is trying to introduce us, as resonantly, as humanly as possible, to a very hermetic, even if garrulous, sensibility. Irwin insists on the centrality of his intuition in the development of his mostly vanished, largely (and deliberately) undocumented pieces and installations, all of which have come into being as questions that kept consuming their answers.

Some history: In 1957, after two stints in the army and matriculation in three prestigious if unsatisfying Los Angeles art schools, Irwin, at 29, was given his first one-man show at the Felix Landau Gallery. He was then painting in an abstract expressionist style. Minutes before his opening, " 'I got that first really clear look at what I was doing, and it was terrible. . . . And I knew that everything I'd been doing hadn't been worth s---.' "

Soon afterward Irwin connected with the Ferus Gallery, "a motley batch of beatniks, eccentrics, and 'art types.' " Irwin remembers it as "very loose and wide open." During the '60s the Ferus became the "seminal source . . . of modernistic art in L.A."

Seminal though it was, the Ferus group, like most of the West Coast art scene of the period, was also ahistorical. It was characterized by insularity, a lack of sophistication, and a disinterest in (if not a distrust of) theorizing.

However, during the late '50s and early '60s, Irwin's work began shedding itself, as it were. His "evocative landscapes" gave way to his "abstract expressionist phase," which delivered Irwin "to the threshold of (minimalism)."

Gradually and always intuitively, Irwin developed an awareness of the crucial importance of a painting's energy field. (In this respect, the work of Philip Guston was a revelation to him.) Irwin began to formulate the challenge as one to "maximize the energy, the physicality of the painting, and to minimize the imagery." (In the mid-'70s, long after he had given up the canvas, the frame and the image, when he was designing installations for rooms in various museums, he tried "to achieve the maximum transformation with the minimum alteration.") Paradoxically, through an ever-widening sequence of strippings away, Irwin pursued his demons unswervingly, in his determination to change the perceptual field of the painting.

By 1970, Irwin had discovered what Weschler calls his "lifethemes: the explication of presence, an awareness of perception." These themes revealed themselves only after courageous experimentation in numerous situations: in his Venice (California) studio; in the desert; with a room that he transformed at the Museum of Modern Art, New York; and with sensory deprivation.

Then, in the early '70s, Irwin, for the first time in his life, began systematically to consider certain works of philosophical speculation. Since that beginning he has been assimilating people like Kant, Hegel, and Wittgenstein, attracted to them originally for the "scale of their ambition" (which is also a reason that Weschler is drawn to Irwin). " 'The idea of being reasonable, . . . to me that's the real jewel in the human crown.' "

Through his intense intellectual research Irwin has become convinced of the "primacy of perception," that "perception precedes conception, that every thought or idea arises within the context of an infinite field of perceptual presence which it thereupon rushes to delimit."

Because of its phenomenologically audacious concerns, and because it is not about images, but rather about "that endless moment of precognitive perception," a quest for "unmediated presence," Irwin's work is exceedingly hard to document, or even describe. You had to be there. Reports are prey to abstraction.

It is much easier to respond to the vibrant, amusing Irwin (in print, at any rate). He tells us about his high school days in L.A. during World War II (which " 'was not reality' " to him and his friends; he was oblivious even to Hiroshima; reality was building cars into " 'cherry' " shape). " 'The car was your home away from home. And you put months and months into getting it just right. Everything was thought out in terms of who you were, how you saw yourself, what your identity was.' " Irwin agrees with Weschler that "his work on cars, more than any particular art classes he subsequently took, might be seen as one origin of his artistic vocation."

Irwin is also most engaging when he confides yet another passion: the art of playing the horses. He has been refining this passion perhaps even longer than he's been painting, and has supported himself intermittently throughout his career with his race-track winnings. Weschler writes that horse racing, after car-building and his Ferus education, "constituted the third most important element in the honing of Irwin's aesthetic sensibility. . . . It was at the race track, more than anywhere else, that Irwin learned the distinction between logic and reason."

About his betting technique, Irwin explains that after you evaluate all the pertinent factual information, " 'It's like you run your hand over the race.' " By this he means that he reconsiders everything according to very subtle feelings that understand the value of the "incidental, the peripheral."

It is this same understanding that Irwin has sought to express in his art and that has made him virtually at one with his work. Indeed, the sense of Weschler's account is of a man whose personal life has always been subsumed by his work; that is, all of his assumptions about human beings are extrapolated from his obsessions, rather than from any awareness of complicated human dynamics.

He contradicts himself grandly. He tends to regard all human systems as reflections of mental organization. Change the way the mind organizes and ipso facto you change every social, political, and cultural system as well. This notion may not be wrong. It's merely wildly unproven.

Irwin remembers his cars and his artist's universe pointillistically, yet he recalls very little of his former marriage, not even where he lived with his wife. (Actually, he was married twice to the same woman. It's tempting to imagine him marrying her for the first time each time.) On their last evening together, in order to divide up their property, he and his wife stayed up all night playing round after round of gin for particular items. This story at once manages to suggest why his wife was persuaded to marry him twice, and why the marriage was doomed from the start. One grasps, too, that Irwin would make a better teacher than he would, say, a parent.

He has, in fact, taught--most notably at the University of California, Irvine. His influence on peers and novices is said to be "immeasurable" but indirect: he has said that "the most immoral thing one can do is to have ambitions for someone else's mind." Still, he has ambitions to change the " 'whole visual structure of how you look at the world. . . .' " At the Whitney retrospective, Irwin created two on-site installations and a sequence of aerial photographs that together were calculated to seduce visitors to transpose the perceptions evoked into the city beyond the museum.

Similarly, after years of isolation in the pursuit of infinity, presence, immanence, Irwin has now returned to the world, perhaps because few artists can afford to ignore indefinitely what Irwin calls the " 'currency' " of our culture. Perhaps because he has fully accepted at last that he, like the rest of us, is within history after all.

In any case, he has been proposing and constructing permanent installations on outdoor sites throughout the United States. " 'After the Whitney (show), I might have just disappeared. . . . But the world always draws you back. . . . The ordinary, could we but see it, is just as extraordinary as the highest consciousness imaginable.'"