The little houses Wright was referring to were the small, glassy boxes Johnson began designing in the 1930s, one of which was Johnson's own dwelling. On first visiting one of them, Wright had asked, "Phil, am I indoors or outdoors?" Wright was himself famous for having designed houses which integrated indoor and outdoor spaces, but he never blurred the line. Johnson all but obliterated it. One of a handful of pioneering American modernists, Johnson became as influential, if not quite as famous, as Wright himself. I think there was a bit of jealousy.
Comparatively late in his career, and many years after Wright had died, Johnson suddenly scandalized a whole new generation of architects by designing an immense Manhattan skyscraper to look, as even the most obtuse critics could see, like an immense case for a grandfather clock. This departure from his earlier style by a distinguished older architect gave considerable impetus to the emerging mannerist post-modernism which has since become the dominant style of architecture. One revolution was not enough for Philip Johnson. I'm sure Wright would have disapproved.
The death of any famous architect invariably brings to mind the case of Stanford White, the brilliant late 19th-early 20th century architect who was shot and killed by Harry K. Thaw about the time Philip Johnson was born. Found not guilty by reason of insanity, Thaw was sent off to a mental institution. The famous tale about him is that, on the way there, he and his guard changed trains, and while traveling between depots, they saw a large, recently constructed public building that had been built in the rather chaotic, eclectic style of the late Victorian period, and Thaw exclaimed "My God. I shot the wrong architect!" Could that be true? Is it possible to shoot the wrong architect? Every one of them has built something for which they probably deserve to be shot. But we forgive them, because they build other things that redeem their arrogance, their presumption, and even their lapses of taste.
What can be said about Philip Johnson? He scandalized Frank Lloyd Wright. He was an iconoclast who came to be respected, then risked that respect by becoming an iconoclast again. He lived in a glass house, threw many bricks, and got away with it. He lived a very long time. Sometimes for better, and sometimes for worse, he was the most influential American architect of the twentieth century. Nobody shot him. I guess that adds up to success.