Nevertheless, I feel the line was blurrier then--perhaps in the spirit of Robert Venturi's "both-and" as opposed to "either-or". That is, there was a giddy thrill behind how the Postmodern spirit opened up the floodgates to practically everything in sight. It wasn't like you were on "one" side or the "other"; it was more like a fascinating moment of anything-goes.
What really ushered in the era of the "sharp line", I guess, was Prince Charles' anti-carbuncle crusade in Britain...
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PLEASE NOTE: Apologies for taking time and space to deal with what many of you undoubtedly will view as side issues, because I believe that they do have profound bearing on understanding some of that mixed reaction to Stern and his work. Johnson once referred to Stern, among others, as one of "... my kids," and what relates to Johnson here touches on Stern and One St. Thomas. Johnson and Stern did post-modern, albeit the latter is more identified with it. Both went on to something else, Stern more of a historical recreation of sorts. And both learned how to navigate the admittedly prickly landscape of architects, although it took Stern much longer, and carried with it a very negative residual effect. Finally, this touches lightly on how perceptions may be formed, by contrasting the reaction of a city steeped in modernist work, Chicago, versus a city that is less so, Toronto.
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It's a great deal more complex than that for the "sharp line," or just "lines," that exists for this building. This board is obviously not a good place to get into this in detail, but I'll give you my thumbnail version, knowing full well that it will exclude much, and obviously there are other equally valid takes.
First. There is a difference between post-modern in Canada and post-modern in the US as to architectural divisions and timeline. Then there is a difference between Chicago's reaction to post-modern and other cities in the US, especially out west.
In reverse order, Chicago was never a hotbed to post-modern. That's largely the result of the influence of Mies van der Rohe and a bevy of his students that went on to become influential architects in Chicago, and the role of the modernist populariser being based in Chicago,
Skid-row Owe-'em and Muddle, when the post-modern era unfolded. But, like any other city, high-profile architects like Johnson, attract clients regardless of style, so his post-modern venture was one of the few exceptions you will see in Chicago.
Across the US, the lines were drawn as far back as the 1970s, as I have stated elsewhere, but these lines while evident in the early 1980s, the rhetoric that accompanied them became more muted. By the time that modernist architecture began to re-take the upper position that it once held in the 1960s, now transposed to late 1980s, the lines were still firmly there but the conflict was transparent and maybe thought to be non-existent to the larger public.
Canada's post-modern ventures were parallel, slightly more delayed, but never as politically charged as in the US, even when the lines belatedly surfaced. In addition, the outward manifestations of post-modernism were never as bizarre as they were in the US. You need only look to the so-called "sunbelt states," meaning Southern and Western US, to sample some of the more unusual concoctions of the post-modern style. Some of these buildings were applauded, others received inflamed reactions, notable even if compared to any other period's reaction to controversial skyscraper architecture. Calgary and Vancouver may seem similar to some of us on this board, but not to the same level nor to the same extent.
Can't argue with your Prince Charles reference, with Toronto particularly relevant for obvious reasons, but this type of politic had less to do with the internal one of architects than with the commissions that were influenced.
Second. With all due respect, quoting Venturi is very misleading.
Venturi never drew sharp lines in the first place. Stern cited Venturi in defence of his post-modernist position, as did others that identified with post-modern, because Venturi was respected on both sides. Ultimately, Venturi's works and his musings belong to that of a precursor and enabler to post-modern rather than a hardcore advocate. Venturi's academic equivalent was Vincent Scully. Stern, on the other hand, while knowing both Venturi and Scully, was initially more hardcore.
From the other direction, some of that "everything goes" for post-modernism is revisionist history. I have no doubt that you've read it, but the facts tend to dispute it, especially when post-modern began and there was a tonne of outright shouting at symposia and forums that were held throughout the US. True, modernists of the Bauhaus line had very narrow definitions of what a building should be, and what materials should be used in construction. But then there were also the Neo-Constructivists, the Neo-Brutalists, and the geometrics of Mid-Century moderne, etc, etc. All of these were modernists as well, under the post-modernist definition, and expressing very different designs, use of glass, and interpretation of form. It is a myth that the so-called modernist group did not offer a number of alternatives, but it is not a myth that post-modernist work tended to look back in time for historical references and stylings to inform their work. This is why I use the words "lines" when I refer to a group that got their collective name from the group which opposed them.
Third. Johnson often didn't get the most stark form of the sharp line for a very interesting set of reasons.
Johnson was not a firm anything, and he was dabbling in post-modern when the Chicago commission came. Johnson was one of those types of architects who could do great work and mediocre, but was always above the fray. This is due in part to his networking skills, and in part to his aid to the careers of so many architects, regardless of their archi-political affiliation. While this building was not one of his great works, and I'll spare you the details as to why, the architects that unmistakingly divided along the lines that I suggest, did so with unusual respect shown toward Johnson, the man.
But divide they did when this building arrived on the scene.