Wendy Lesser brings her new biography, You Say to Brick: The Life of Louis Kahn (Farrar, Straus & Giroux; 397 pp., $30), to the Free Library on Thursday. It traces the panoramic life and equally panoramic work of Kahn, who emigrated with his family from what is now Estonia to the United States in 1906, attended Central High School and then the University of Pennsylvania, and became one of the 20th century's most admired architects.

Lesser's book is lyrical and personal. Some of its revelations about Kahn's intimate life have attracted comment, but its main love affair is with his great buildings. Working closely with Kahn's children, with archivists at Penn, and also visiting almost all of Kahn's major buildings, Lesser builds a truthful, appreciative profile of Philadelphia's most prominent modernist. She spoke by phone from an office at the Threepenny Review in Manhattan, a town in which she lives, as she puts it, "5½ months out of every year."

What brought you to write about Louis Kahn?

I wasn't going to write another biography. My [2012] biography of Dmitri Shostakovich [Music for Silenced Voices], had been so hard. But then I visited Franklin D. Roosevelt Four Freedoms Park on Roosevelt Island in Manhattan, one of Louis Kahn's last designs, and that was a turning point. I went just to take a walk, and I fell in love with it. More than that, I had the feeling I sometimes have when art strikes me: I have something to say about this place. It would turn out to be much the hardest book I ever wrote.

Research must have taken you places.

I couldn't have written it without his three children, Sue Ann, Nathaniel [maker of the 2003 film My Architect], and Alexandra. They agreed to be part of the project, and as we went along, they kept telling me more and more revealing things. William Whitaker, curator and collections manager of the Architectural Archives of the University of Pennsylvania School of Design, was also a bigger and bigger help as we went on. I even located Fred Langford, the "concrete man," who helped Louis Kahn make concrete into a work of art. Fred's in his 80s and lives out in Cape May.

He earned his renown as an American architect - but his is really an immigrant's story, isn't it?

I was just at the Kimbell Art Museum in Fort Worth for a panel discussion . . .. And Sue Ann Kahn said this wonderful thing: Here was this story of an immigrant Jew who grew up poor and came to this country - and went on to build the Dhaka Assembly Building [in Bangladesh], the capital building of a foreign country, a Muslim country, whose people see it as a building dedicated to democracy. And that building includes a mosque. That building embodies democracy. She got a spontaneous ovation.

Polygamy is a theme in much discussion of Kahn. What line, if any, can we draw between his alt-relationships and his art?
I want to say that the life as a whole is important, and shoving personal facts under the carpet does not do a service to Louis Kahn. The three children made it clear they wanted a book that brought out the truth, the fullness of his personality. They did not get to see their father very much, but they did love him and felt loved; they are not neglected children in any sense. And they wanted me to tell as much of the truth as I could find. It's not a gossipy thing; it's an acknowledgment of who he was.

As for relating his personal life to his art, there's a photo of him shooting a bow at a camp in 1936. He's very strong, with a powerful physique; he's comfortable in his body.

Architect Louis Kahn at Brookwood Labor College, 1936. Anonymous photograph from the collection of Sue Ann Kahn.  

I saw that and thought: "I get it: Here's a man who felt like that in his own body, that life takes place in the body. That could lead to love affairs - and to the creation of buildings like his, buildings that acknowledge you as a body, make you feel enclosed but elevated, grander, where the light comes through just for you." His sense of inhabiting his own body is the link.

Keep going: Tell us more about what a Kahn building is like.
All his great buildings have an interest in materials, and one of his materials was light, how natural light can come in through windows, skylights, holes in the roof. Light becomes one of these natural materials. He was also a narrative artist. In his buildings, there's a plot, with surprises; you find yourself being altered as you go from beginning to end. And, again, there's that sense of the scale of the individual human body and this massive building protecting it - and enlarging it. You as an individual are never rendered antlike; you are being enlarged, made greater. You get to be human on a grander scale.

Do you have a favorite?
Each one I'm in, I think, 'This is my favorite.' That's the way I felt at first about the Salk Institute [for Biological Studies] in La Jolla. But I do remember the feeling of being in the Dhaka Assembly Building and feeling nothing could ever be better than that.

The  mosque   in the Dhaka Assembly Building, designed by architect Louis Kahn. Photograph by Richard Meier, courtesy of the photographer.

It is awe-inspiring in every way. If everybody could see that building, Louis Kahn would be king of the architecture world, no doubt about it.

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