Rem Koolhaas is the Dutch architect who came to the U.S. in the '70s to find in Manhattan an unwritten manifesto--part Surrealist, part rationalist--for a metropolitan "culture of congestion." His Delirious New York, of 1978, sounded a new note in architecture, urbanism, and the manner in which they might be related to one another. It was at odds with urban planning and "renewal," out of sync with both a European "contextualism" and an Asian "critical regionalism." Yet it would lead Koolhaas to what many now recognize as some of the most significant architecture to have emerged in the last half-century. That is why Koolhaas' current show at the Museum of Modern Art, curated by Terence Riley, has been so eagerly awaited. At last old New York gets a look at this work.

In addition, Koolhaas is about to release a brick of a book entitled S, M, L, XL, which details what he and his Rotterdam-based Office for Metropolitan Architecture (O.M.A.) have been trying to do since Delirious New York. Mixing projects with analyses, diaries, fables, cartoons, and a manifesto ("Bigness" appears in full alongside the following interview), and equipped with a running dictionary of a strange new language, the book tells a tale, a great contemporary architectural odyssey--the story of the thinking and seeing that inspired the work on view at MOMA, the story of how this architect came to "think big." The book is itself a singular creation, built up by accretion from diverse components at a scale that discourages any single overarching view, obliging one instead to find one's own ways in and out of it. It is an XL book, going off in many directions at once. The complexity and density realized through Bruce Mau's multilayered design are relieved by a "light" tone and style, a sense of experiment and "gay science."

A leading concept is "Bigness." Koolhaas says that past a certain point, sheer size surpasses what can be contained within classical principles of organization, altering the very nature of architecture, its aims and aspirations. He declares that such Bigness is the most basic result of the past 150 years of building, and, following various phases of modernization, has spread almost everywhere, attaining megaproportions that stretch and distort the very idea of the city. Yet we have lacked an adequate conception of this condition. Despite our fancy new theories, we have yet to grasp what it is; despite our fancy new architectural styles, we still have no idea of what it might yet look like. Bigness remains as much as ever a question mark, and a cause of "big mistakes." For we seem to have lost, or given up, the sense in which architectural design is more than a simple matter of decoration and style; it is a way of seeing things unseen in our condition, of releasing other new possibilities in our ways of being. We have retreated into "deconstructive" formalisms or "wired" fantasies of cyberpower, and left the real world to such things as the professionalized, atrium-obsessed, surreal "disurbanism" that calls itself "post-Modern." To see and conceive Bigness is to change our habits of thinking. After the failure of Modernism and of urban renewal to grasp and intervene in the constitutive processes of the city, we must learn how to "think big" again. To this end, O.M.A. would mobilize a sort of "war machine"--it would engage an ongoing struggle with developers, politicians, engineers, government agencies, and professors to introduce the fresh air of a new kind of urbanism, a new way of thinking about cities, which analyzes specificities while multiplying possibilities in the manner of Nietzschean "gaiety."

Koolhaas' "Bigness" is not Promethean, then; it is quite unheroic, even indifferent or impersonal. It is not "colossal" or "sublime," it is labyrinthine, and the point is not to find a way out but rather to find new ways of moving about within its complexities and specificities, reinventing and reassembling its paths. Bigness is thus an uncontrollable condition we can diverge or displace from within--not an ideal, not a master plan--and that is why it denies what much of our urbanism has supposed: that we might actually make cities. In the fantasy that we can do so, Koolhaas finds a congenital hubris.

"To think big" is to check architecture's usual "megalomania" to control or plan everything, and to work instead with unnoticed possibilities in a situation we realize we can't completely master. It is to accept that cities are clashes of forces with unpredictable outcomes, loose assemblages from which new things and new connections derive, as if by alchemy. It is to start to think in terms of the "events" that our urban (and even dis- and posturban) condition thereby releases, the peculiar points--what we might call the urban "virtualities"--at which cities start to become other than they are. Only then will we be able to see the real questions Bigness poses. For despite our sociologies of "modernity," we have yet to grasp the drama, the consequences, the possibilities of the successive "modernizations" that have spread Bigness across the globe, as now through Asia on the most massive scale ever; for all our nice nostalgias for "public space," we have yet to confront the questions of the new kinds of sociality this condition makes possible; and for all the hyped futurism about "virtual" infrastructures, we have yet to get a fix on the "real virtualities" of the specificities with which Bigness confronts us.