Source: The Phoenix
Date: January 20, 20014
Byline: Izzy Kornblatt

Book Review: Planning Philadelphia

The usual rap on post-World War II city planners is that they ruined our cities with their highways and shopping malls, and even now we are not entirely done recovering from the damage they did. At least in my experience, this view is held not just by city-dwellers but also by many people who themselves live in suburbs, commute via highway, and do much of their shopping at malls. This is because cities have recently become fashionable again, and no one wants to admit to any affection for the suburbs.

But you cannot seriously consider the value of cities if you write off the suburbs, if you ignore the pull they exerted over several generations of Americans and the appeal they continue to hold today even for so many of their avowed critics. A serious consideration of cities needs to acknowledge the fact that the present infatuation with cities is not so different from our parents’ and grandparents’ with the suburbs. Of course, there is nothing wrong with simply going along with the trend and enjoying cities as much as everyone else seems to these days. The problem is that too much of the supposedly serious discussion of cities these days takes as a starting point the unquestioned assumption that cities are good and shopping malls and all they represent are just obviously inferior. This typically leads opinion about cities down a pretty tiresome path to a set of beliefs about how cities should be developed held almost universally by people who consider themselves interested in urban planning: build parks, prioritize pedestrians and public transit over cars, build community gardens, reclaim waterfronts, build mixed-use, mixed-income developments, build parks, attack gentrification (a little guiltily), build parks, build community centers, build parks.

None of those views are necessarily wrong. Some of them are simply practical: now that we all care about cities, what do we need to build there that people will like? Parks, certainly, and community centers. Others are political: despite changing demographic trends, poor people do remain concentrated in cities and we need to figure out the best ways to help them, hence gentrification relief and investment in public transit. What’s wrong is just that more needs to be said if we are going to do anything new and interesting with urban design. Urban planning needs to be about more than just density and public amenities. Urban planners now should rethink the relationships between roads and pedestrians (and that does not mean just burying all the “ugly” highways), between suburbs and cities, and between public and private spaces; and ask larger questions about the goals of planning: what does it mean, in the end, for a city to be well designed? If the fashions are always changing, as they are, how can any kind of plan be expected to be something more than simply what the most people want at any given time?

The new book “Ed Bacon: Planning, Politics, and the Building of Modern Philadelphia,” by Gregory Heller, is a good start in pushing the discourse about cities in a good direction, if only by virtue of its subject matter. Edmund Bacon, often thought of in conjunction with New York’s Robert Moses and Boston’s Edward Logue, was a postwar city planner who, in his heyday, was one of the most important, progressive, and interesting planners in the world. (In fact, of the three, Bacon was the only actual planner.) Bacon’s major life work was re-imagining and slowly reconstructing a decaying Center City Philadelphia. He served as the executive director of Philadelphia’s City Planning Commission from 1949 until 1970, though he remained somewhat active in city politics until the early 2000s (he died in 2005). He appeared on the cover of Time Magazine in 1964. Despite his former fame, Bacon is not known well now: this is just the second major book about him. The renewed interest is welcome, because any careful examination of Bacon’s work and influence, and this book in particular, very clearly give the lie to the notion that all post-war city planners cared about were highways and malls. The book challenges the conventional narrative about cities that has underpinned too much lazy, regressive, faux-1900 planning; it makes a whole shoddy fiction fall apart. This is because when you see Bacon not as an autocrat and not as a hater of the poor or of lively neighborhoods (“We’ll just pave that over with a ten-lane freeway”), but rather as a sympathetic and engaged planner who loved the city as a concept and his hometown in particular, you have to recognize the seriousness of the theoretical and practical difficulties he faced: you have to understand suburbia as a considered, not at all evil experiment in living; you have to see the radical steps taken in the 1960s in Philadelphia and elsewhere to remake public spaces and roadways as necessary and important. Above all, you have to appreciate the pressures that the postwar era put on the city and see beyond the current fashion that has declared postwar planning and architecture “out.”

One criticism I have of the book is that Heller doesn’t do more to push that line of thought. He too often rushes to declare Bacon “ahead of his time” for his love of cities and dislike of cars, instead of even-handedly considering Bacon’s theoretical successes and failures. Bacon is indeed relevant because he had ideas about cities, but those ideas should be able to stand apart from the fact that a couple decades after Bacon retired people started moving back to Philadelphia. Heller also dodges theoretical concerns a little bit by sometimes treating Bacon’s style as planner-implementer (Bacon often worked closely with private developers) as his most important contribution to planning. The question of how planners hired by a city can influence private development is certainly important, but it is really just practical. From the perspective of someone interested in how the city of the future should look and function, it is not all that interesting.

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Still, Heller does a good job going through Bacon’s career and explaining and assessing each of his projects. His book is lucid, sympathetic, and methodical, though I would have liked to read a little more about the design of some of the largest projects Bacon worked on.

Bacon’s planning and design philosophy, which he explained in his 1967 book “Design of Cities,” is decidedly modern: Bacon, like most modern architects, thought architecture should express “the spirit of the age.” The pared-down industrial look of modernist architecture was intended to formally recognize heavy industry and the machine as the great features of the modern era. It was time to stop hiding such things behind increasingly tortured classical facades and instead tie form to function. Machines, after all, are all about perfectly efficient functioning. A famous example of this is the great French architect Le Corbusier’s affection for horizontal strip windows. Since modern engineering had allowed us to build load-bearing columns instead of walls, we should express that fact with windows that clearly illustrate walls’ new purely covering, non-structural function. A wall with a window cutting horizontally across it clearly is not holding up the building.

Bacon, along with other planners of his time, wanted to extend these ideas beyond architectural details. For example, he thought modern city planning needed to acknowledge the centrality of the car to modern life. Praising Brasília, the capital of Brazil designed by Lucio Costa and Oscar Niemeyer in the 1950s, Bacon wrote that the highway, too often thought of “as comparable to plumbing facilities,” in Brasília “has come into its own as an architectural work and is an integral element in civic design.”

He was even more taken with the city’s separation of pedestrians from automobiles; he especially liked the pedestrian-only zones: “The entire roof of the Congress Building is paved with marble, and access to the balusterless pedestrian area is provided by the ramp leading from the ground below.” Bacon actually did not always or even often have much affection for highways, but the idea that cars and people should be separated, known as a Radburn principle after a famous development in New Jersey, proved to be of tremendous importance for Bacon’s work in Philadelphia.

Bacon was trained as an architect at the Cranbrook Academy of Art in Michigan, one of the most important centers for modern architecture in America in the early-to-mid 20th century. There, and on throughout his career, first in Flint, Michigan, and then in Philadelphia, Bacon developed relationships with some of the most important architects, planners, and thinkers of the century, including Eliel Saarinen, Louis I. Kahn, Oskar Stonorov, George Howe (architect of the first major modern skyscraper in America, Philadelphia’s PSFS tower), Constantinos Doxiadis, R. Buckminster Fuller, Vincent Kling, and Lewis Mumford. But this was no exclusive club. Bacon committed himself to making the ideas and processes behind his plans accessible to all, and to making planning a real concern for the people of Philadelphia. None of his writings are technical or even moderately difficult. In 1947, he organized the famed Better Philadelphia Exhibition on the second floor of Gimbel’s Department Store on the east end of Market Street. The exhibition sought to explain the job of the City Planning Commission to the people of the city, and to explain the city’s growing challenges, most notably the decline of industry and tax revenues and the rising poverty rate. It also sought to present an optimistic and ambitious vision for the city’s future. “The beginning of the show built drama, taking visitors along a mysterious dark foyer,” writes Heller. “A mirror would disappear, magically replaced by a view of a panorama of a future Philadelphia.” The exhibition was a tremendous success, attracting over 385,000 visitors in its one month run.

Bacon continued to try to keep people informed about his work throughout the rest of his career, but his focus soon shifted to actual planning when he was named director of the planning commission. In the postwar era, the federal government was generous with urban renewal funds and there was extraordinary opportunity to remake cities that had been built for previous centuries. In 1950, Center City Philadelphia was dominated by two huge above-ground train stations, the Pennsylvania Railroad’s Broad Street Station, and the Reading Railroad Terminal on Market Street, which sat on opposite sides of City Hall (there was also Suburban Station and 30th Street Station, which are both still in use). Automotive access to the city was not very good, and beautiful neighborhoods, such as Society Hill, were falling into disrepair. Luxurious department stores were threatened by suburban shopping malls. The Delaware riverfront was a poorly used industrial zone. Independence Hall wasn’t accorded any significance in the layout of the city. Philadelphia was in serious need of updating if it was going to be a city people wanted to live in and do well in the era of a service-based economy.

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Bacon tried to do just that in his two decades at the helm of the planning commission. His major projects included the revitalization of Society Hill (including the Society Hill towers), the Penn Center office building complex and the parks and plazas near it, the Gallery at Market East shopping mall and adjacent Market East regional rail station (and the Center City Commuter Connection tunnel that serves it), Independence Mall, the plaza at Penn’s Landing, housing in the far northeast area of the city, the since-reversed removal of automobiles from Chestnut Street, and several downtown highways. It is important to understand that Bacon often did not have much final say over these projects. As mentioned, Bacon often worked with private developers who usually bought into his general schemes but often rejected the nuts-and-bolts, particularly the more expensive ones, of his visions.

As a committed modernist, Bacon believed in the value of the planner’s having a total vision for the city. In “Design of Cities,” he presents each of his major planning projects connecting and bettering each other, together forming a reinvented downtown for the late 20th century. Center City was to be encircled by highways: to the east, the Schuylkill River Expressway; to the west, the Delaware River Expressway, to the north, the Vine Street Expressway, which would pass under the Ben Franklin Parkway; and to the south, the Crosstown Expressway, which was to run along South Street. The highways were to be easily crossable, and the Delaware River was to be integrated into the plan with a green riverfront path and several riverfront amenities, including what became Penn’s Landing. The Schuylkill was to be integrated as well, through the eventual construction of the Schuylkill River Park. West of City Hall, the massive Broad Street Station complex would be torn down and replaced with Penn Center, a complex of office towers set above an open-air lower level concourse with shopping and access to the subways and Suburban Station. Views of City Hall were to be preserved, and a set of new parks and plazas around the area would make the whole City Hall and Penn Center a central gathering place for the city. East of City Hall, Reading Terminal would be replaced with a new underground regional rail station connected underground to the Penn Center concourse and to a set of new buildings on Market Street housing restaurants and shops, helping to revitalize the city’s struggling department stores. East Market Street was to become a multi-level street, with pedestrian paths both above and below cars, plus regional rail and subways. Further east, a new four-block park was to be created in front of Independence Hall, lined with important corporate buildings, and connecting Franklin and Washington squares. This park would connect via “greenways,” green park-like pedestrian pathways, east to the waterfront and southeast to a revitalized Society Hill, where new upscale modern apartment towers would contrast nicely with restored historic brick houses.

Bacon saw this revamped downtown as just the first step in a revitalization of the whole city. He thought the downtown had to come first, and then the strengthened city could move on to tackling its other issues, such as its high poverty rate, head-on (which is not to say that he thought anti-poverty programs had to wait until he was done with Society Hill). He thought that a primary task for the city was making itself great again.

It is hard to say how well many of Bacon’s projects worked out, and in the cases where they clearly didn’t, to what degree Bacon’s plans are to blame.

Penn Center is clearly an abomination. Its generic slab office towers, decrepit, empty plazas, and dingy underground concourse are like a parody of rote office hell. The places where people need to walk are sparse and boring; there is nothing much to do except in the underground station, where the low ceilings, labyrinthine layout, and lack of connection to the street level make spending time very unappealing. As Louis Kahn famously put it, if the plan had been submitted by a first-year architecture student, the grade it would get would be zero. But Kahn was not criticizing Bacon. The problem was that the development was controlled by the Pennsylvania Railroad, which understandably preferred to develop in the easiest and most profitable manner than to act in the public interest. Had the original office buildings not been cheap, boring clones, had they been sited properly, and had the underground concourse been effectively connected to the street level, things may well have been quite different. After all, the concept of office towers connecting to an underground train station is not a bad one.

The story at Market East is similar. Early drawings by various architects, including the renowned designer of Swarthmore’s Lang Music Building, Romaldo Giurgola, show an effectively layered urban environment, not a depressing enclosed mall. Giurgola’s series of identical modern towers effectively frame City Hall and connect pedestrians with the street while making the bold move of not treating the street as the centerpiece of the urban landscape. The mall that was finally built and that still stands now, the Gallery at Market East, is not an architectural achievement (its blank walls leave a lot to be desired), but it has succeeded over the years at keeping shopping, particularly cheap shopping, in Center City. The mall is used by people of all income levels, unlike the much more “in” Rittenhouse Row just a few blocks away. Even better than the mall is the regional rail station it is adjacent to, Market East, which was championed by Bacon but not completed until the mid-1980s. Formerly, inbound Reading regional rail trains had all stopped at Reading Terminal before heading outbound again, while inbound Penn Railroad regional trains had all stopped at Suburban station before heading out again. The two networks were entirely separate, like the Long Island Railroad and Metro-North in New York City. A new four-track tunnel, the Center City Commuter Connection, was built connecting all the Reading lines with Suburban Station, and as part of the project the new underground Market East Station replaced Reading Terminal as the major regional rail station in eastern Center City. This freed up a good deal of space for development that had previously been taken up by above-ground tracks and other related facilities. The old Reading Terminal building was preserved, as was the still-popular market on its first floor, and is now used as part of the Pennsylvania Convention Center. The whole project, while expensive, allowed for a much better-connected rail system, better-used above-ground space, and a new well designed station that connects to the Gallery at Market East.

The revitalization of Society Hill is Bacon’s clearest success story purely in terms of goal accomplishment. What was once one of the poorest neighborhoods in the city is now safe, well off, connected with beautiful greenways, and overlooked by three elegant residential towers designed by the architect Ieoh Ming Pei. No cheap historical imitation architecture was employed in revitalizing the neighborhood. Bacon’s approach was innovative for its time: he restored the historic homes, tried to keep the existing feel of the neighborhood, but insisted that new construction be clearly modern in style so as to distinguish the old from the new. Less fortunately, many poor people were displaced by the selective demolition that was necessary and by the rising property values that the neighborhood’s revitalization caused. Bacon himself was not blind to this. “I knew it was cruel while I was doing it,” Heller quotes him as saying. “But think of Philadelphia if Society Hill was still the way it was. It was more important to restore this area than to maintain the low-income residents.”

The plaza at Penn’s Landing and other riverfront amenities that Bacon hoped would revitalize the Delaware River waterfront have generally not done so, mostly because of the Delaware River Expressway. Really none of Bacon’s highways are very popular. The proposed Crosstown Expressway, which would have crossed Center City somewhere near South Street, was thankfully killed by anti-highway protests and general negative sentiment. The Vine Street Expressway, which did not fully open until 1991, is not loved by many of its neighbors, but is an important road for the city. It relieves congestion approaching the Ben Franklin Bridge and provides a fast route across the city. Bacon, Heller writes, always promoted the highways the city wanted in his capacity as director of planning, but privately he had doubts. He personally disliked cars and thought that the American infatuation with driving would pass when we ran out of petroleum. It is undoubtedly good that Bacon fought for public transit and did not put cars first in his city, but on the other hand it is also good that Philadelphia built the highways it needed in order to be a functioning modern city. Highways, as Bacon himself recognized when he wrote about Brasília, are not inherent abominations. It is the modern architect’s job to make these huge, necessary pieces of infrastructure express something, as Robert Moses did with the best of his New York parkways.

I think that Independence Mall generally works well. Cities need breathing room, and this park fits the historic site well: it is well proportioned, and the modern buildings that surround it are pleasantly unfashionable and unkitschy. Unfortunately the recent redesign of the mall has probably done more harm than good, as Bacon publicly complained it would. The closing of Chestnut Street to cars did not work out; Heller argues that this was because the road was never really effectively closed. A planned light rail line down the pedestrian street was never completed, and instead SEPTA used the street as a kind of bus thoroughfare, which ended up being enough like car traffic to stop the street ever really becoming pedestrianized. The street was reopened to traffic in the early 2000s, which is just as well, because it works just fine as a regular old street. Bacon’s housing projects in northeast Philadelphia are reportedly less than stellar, though I have never been to them.

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In 2000, Philadelphia began a significant period of population gain for the first time since 1950. The city’s population had fallen from nearly 2.1 million in 1950 to just over 1.4 million in 1999. The U.S. census estimates that by 2012 it had risen to almost 1.55 million. Consequently, the tax base is growing and city finances are looking up. This summer, Standard & Poor’s upgraded the city’s bond rating to an A-minus, its highest level since 1979. Center City is again a 24-hour downtown, in part thanks to the efforts of Paul Levy’s Center City District, and is in the midst of another residential construction boom. A bike-share is scheduled to open next year. SEPTA ridership is up, and car ownership is down. The city’s arts scene is doing very well (though an ongoing Inquirer series is exploring whether there is enough funding for that to last). A number of major cultural projects have recently opened or will soon open on the Parkway. New parks have appeared around the city, including the Schuylkill River Park Bacon envisioned, and more are planned or under construction. A major reworking of Penn’s Landing and the whole Delaware riverfront is in the works. This summer, Mayor Michael Nutter released a comprehensive plan to address the city’s poverty, which remains the worst of any of the ten largest cities in the country. Former Mayor John F. Street’s Neighborhood Transformation Initiative, through which the city tore down thousands of abandoned buildings, seems to be paying off. On the whole, there seems to cause for optimism about the city. This is not to minimize the city’s serious problems: poverty, continued segregation (and attendant stigma against poor black and latino neighborhoods), schools in crisis, underfunded public transit. (At least in the last two cases, decent state funding support would go a long way in improving things.) My point is just that the city seems able to take care of itself in a way it has not been for a long time.

Much of the major construction in Philadelphia over the past fifteen or so years has been quite good. The Kimmel Center, architect Rafael Viñoly’s grand performing arts center on South Broad Street, is an extraordinary building, despite some issues that are still being worked out. Its huge glass barrel roof and rust-colored red brick walls recall the old Broad Street and Reading Terminal train stations, and yet they flip the modern/industrial paradigm of form-follows-function on its head: the grand glass roof is purely decorative; and the result is a fascinating aesthetic experience of a city emerging from its industrial past. Frank Gehry’s underground expansion of the Philadelphia Museum of Art seems promising, though I have no idea when it’ll actually be finished. The new Barnes Foundation looks nice, though I haven’t been inside it yet. And the new Dilworth Plaza in front of City Hall, which will be completed in 2014 and will replace one of Bacon’s least fortunate public spaces, is shaping up to be one of Center City’s best parks, on par with Rittenhouse and Washington squares. The design, by the Philadelphia architecture firm KieranTimberlake along with a bunch of associates, is pretty understated but seems thoughtful and will feature what from the plans and renderings looks like a fascinating interactive, moving sculpture by Janet Echelman: five-foot-high illuminated moving curtains of water that will trace the movement of subways and trolleys below in each line’s color.

The City Planning Commission, which in recent decades had been a shell of its former self, has under Mayor Nutter undertaken some of its biggest work since Bacon’s days. In 2011 it released “Philadelphia 2035,” a comprehensive (and by comprehensive I mean 228-page) master plan for the city, and now it is working on individual district plans for the 18 districts it has divided the city into. Several have already been adopted, including a plan by KieranTimberlake and some more associates for the central Delaware riverfront. Undoubtedly there are some good and important ideas in these plans, but beneath the excited language and rosy vision there’s a disturbing lack of ambition to them. Ed Bacon wanted to remake Philadelphia; today’s planners want to turn the plaza at Penn’s Landing into a grass lawn. Philadelphia in 2035 looks an awful lot like Philadelphia today, but with a lot of people very excited about RENEWING and CONNECTING all of these COMMUNITIES. There are really no ambitious proposals in the plan. There should maybe be a subway line through north and northeast Phila., the planners think, but they don’t really think funding will come through for that, so… it’ll probably be an improved bus line, if it happens at all.

In that case, and in others, the lack of ambition can be easily pinned to a lack of available funds. Federal urban renewal funds are just not available like they used to be, and if the Pennsylvania legislature can’t pass the necessary legislation to fund the maintenance of SEPTA’s current system, what is the chance they’ll shell out for several new subway lines? But the larger reason for the lack of ambition, and likely also at least part of the reason for the lack of funds, is that our attitude toward urban planners has changed radically since Ed Bacon enjoyed popular support in the 1950s.

In 1961, Jane Jacobs published her famous book “The Death and Life of Great American Cities,” which would become the bible of a new movement in city planning. The new movement’s tenets are simple: don’t screw with neighborhoods, and give the people what they want. She understandably disliked the neighborhood-wrecking wholesale demolition that Robert Moses advocated for in New York in order to build his highways, and was revolted by radical modern ideas like Le Corbusier’s plan for Paris which involved the replacement of hundreds of blocks of old buildings with a perfect grid of identical modern skyscrapers served by large highways. She thought supposedly great modern architects and planners had forgotten that people need to make cities their homes, and that they do so by developing neighborhoods over time in many small ways, not through large development projects.

Jacobs did not much like Bacon’s work, though she did comment positively on Philadelphia’s efforts to combine historical preservation with modern development. Heller argues that Jacobs must not have understood Bacon very well, and there may be some truth to that, though it seems to me that their views of the city were too fundamentally opposed for her to have really liked his work even had she better understood it. Bacon was someone who thought that you could remake cities; he saw the city as an “act of will.” Jacobs thought that neighborhoods should be left alone, and in the cases of very poor, dangerous ones, they would “unslum” over time. That view turned out to be wrong. Poor neighborhoods will certainly gentrify, but that hardly helps the poor people who originally lived there. In any case, Jacobs’s criticisms of Bacon and his colleagues stuck, and the planning profession shifted. Soon the dominant mode of planning was “New Urbanism,” a movement which essentially called for the construction of imitation-historic neighborhoods, explicitly or implicitly. New Urbanism is basically what most people who like cities these days automatically subscribe to.

Of course, not all ideas espoused by the New Urbanists are bad. Transit-oriented development, which is exactly what it sounds like, is effective especially for affordable housing. And many of Jacobs’s criticisms of the planning and architecture of her day did deserve to be taken seriously. She was right that historical preservation and respect for existing neighborhoods were lacking in Robert Moses’s vision for New York. She was right that some modern architects’ ideas of pedestrian spaces were a real mess. (See the plaza outside Boston City Hall.) She was right to emphasize that diversity of development is an essential ingredient in a great city. She was right that massive public housing developments often did more harm than good, and she was right to point out certain uncomfortably totalitarian tendencies in modernism. But those valid points did not need to take ambition out of planning. On a theoretical level, the New Urbanism that Jacobs ushered in is a fundamentally defeatist planning philosophy. It essentially says that the best planning we can do is to imitate what we did hundreds of years ago. There is no room in the New Urbanism for rethinking spaces, for bold experiments in living. New Urbanism pretends that the only way to serve people’s everyday needs (accessible stores, outdoor space, places to sit, shade, etc.) are through the framework of the 19th century (plus an awkward allowance for parking garages), as though modern architects hadn’t proved that wrong decades ago. New Urbanism reaches its disturbing logical endpoint in the English town of Poundbury, an entire faux-18th century town built since the 1990s in an apparent effort to pretend away modern life, except in the case of parking spots. (Prince Charles, known in the world of architecture for being generally ignorant about architecture but still opining frequently and publicly about it, has been one of Poundbury’s fiercest advocates.) New Urbanism bills itself as progressive, sustainable, and all the rest, but really it is conservative. It pretends that the only or best way to be progressive is to try to further social goals through that same outdated framework.

In fact, the postwar city planners who the New Urbanists despise, or at least the best of them, were the real progressives. Bacon, as he said explicitly and repeatedly throughout his career, always saw integration and freely available high-quality affordable public housing as essential to any decent city. He also was no high-handed autocrat. Even though some of his projects left people angry, Bacon made considerable effort throughout his career to get public input on his projects. He argued in his “Design of Cities” that good planning is an essentially democratic enterprise. He loved cities, he loved parks, benches, and pedestrian spaces. He stood up for people using those spaces in all kinds of ways: in 2002 a 92-year old Ed Bacon skateboarded about 50 feet to protest John Street’s ban on skateboarding in Love Park (which Bacon had helped design almost 40 years earlier, certainly not with skateboarding in mind). He thought diverse styles were essential to living cities. He just also thought that it was permissible for the planner to have a vision, push for it, and ask people to change their routines to accommodate something radically new once in a while.

The most interesting planning and architectural work of today that I know of is being done by architects like Rem Koolhaas (author of the book “Delirious New York”), Peter Eisenman, Rafael Moneo, Rafael Viñoly of the Kimmel Center, and Zaha Hadid, who I guess could be described as post-post-modern. The postmodernists rejected the modernists’ insistence on a straitjacketed form-follows-function aesthetic (because it really was just an aesthetic); and their sweeping desire to remake the built world. Architects like Koolhaas and Eisenman accept many of the post-modernists’ points but retain from the modernists tremendous ambition, faith in architecture’s ability to transform experience, and a commitment to the present: we have to think about and rethink architecture as we know it now, no longer tied to function as the modernists had it, no longer tied to classical principles of design, but simply as presenting tremendous opportunity to affect how people experience the world. In one of his most interesting projects, the student center at the Illinois Institute of Technology in Chicago, Koolhaas deliberately sited his building beneath an elevated rapid transit line, then insulated the building from the loud trains by building a large, structurally independent elevated tunnel to surround the tracks and trains. The result is a building that weaves and stretches around the tunnel: it is always independent from and yet intimately connected to the city’s transit system, which probably mirrors many students’ relationship with the surrounding area of Chicago. It is a great building that could only have been built by an architect interested in the present.

Ed Bacon was similarly committed to the present. He always sought to be at the theoretical cutting edge of his field; he wanted Philadelphia to be at the center of the world of progressive urban planning, and, for a time, he succeeded. But “Philadelphia 2035” lets him down. The city deserves much better. The Parkway, Delaware waterfront, Gallery at Market East, and labyrinthine underground concourse network could all do with complete rethinkings (and that’s just in Center City). Could there be a way for a renovated Delaware Expressway to be not a barrier to the river but somehow an integral feature of new public spaces on the river? Maybe the answer is no, the highway is just too big and loud, but that’s the sort of question that needs to be asked.

And it will be important for Philadelphia going ahead not to make itself too similar to other cities that have successfully gentrified themselves and in the process lost much of the grit and texture that made them interesting in the first place. When I first walked around Philadelphia after coming here last year, I was taken with how it was a city that has empty lots with murals, and doesn’t feel sparklingly clean or new or rich, and knows how to go about the business of being a great American city without falling in love with its own image of itself as a great American city, like Manhattan or Boston. In this way it is more like Chicago and Baltimore. But New Urbanist-style clinging to the past is not the way to preserve what’s appealing about the city’s character. After all, Philadelphia did not get where it is today by being shy about planning. If the city wants to remain alive, it will have to take the gamble of change. To adapt a philosopher’s line, living cities are not finished pieces of design; they become what they are by constantly redesigning themselves.