Marvin Knopp was a grand man and a grand mathematician. He was
generous and thoughtful with a warm and delightful sense of humor. He was the only mathematician I knew who eschewed e-mail. I was never certain of his motives, but I have to say that I admired his stand against one of the great time sinks of modern life.
At his 73rd Birthday Conference in Philadelphia in January, 2006, I remarked that Marvin had now clearly assumed the leadership of the Philadelphia school of modular forms whose magnificent history and achievements date back to Hans Rademacher and his students in the 1930s. Now, sadly, Marvin is gone with his friends and collaborators left to carry on and to honor his legacy.
This is a deeply sad moment. We all mourn Marvin's passing.