Mr. Michaelis referred to numerous interviews throughout Charles Schulz’s life in which he talked about his own "melancholy" and anxieties. "I have this awful feeling of impending doom," he said on "60 Minutes" in 1999. "I wake up to a funeral-like atmosphere." Many portraits of Schulz pick up the same theme. Rheta Grimsley Johnson’s 1989 biography, "Good Grief: The Story of Charles M. Schulz," similarly describes him as depressed and plagued by panic attacks, despite a large family and mammoth financial and critical success. Nor does it seem that Mr. Michaelis made a secret of his perspective. He wrote an appreciation of Schulz in Time magazine in December 2000 after his death at 77 in which he clearly laid out the thesis he expands on in his 655-page book, sometimes word for word.