THE LONG SESSION.(David Sylvester)

IT'S HARD TO BELIEVE David Sylvester is no longer with us. On both sides of the Atlantic, his imposing presence--a huge amalgam of mind, body, and passion-seemed a permanent fact; and his death on June 19, after a prolonged battle with cancer, feels as unreal as the news that a mountain on our horizon has vanished.

I cannot remember the art world without David's looming large. Only last October, in Berlin, I came upon him by surprise while touring Daniel Libeskind's Jewish Museum. The effect was hallucinatory, with his dramatic figure and oracular voice radiating throughout those ...