That's sad; he was a tireless pursuer of bunkum. The world is a little more credulous without him.
Note added August 11: A friend sent me a follow-up note about Klass. In a UFO newsletter/mailing list called "Saucer Smear", Klass left this message for UFO believers:
The Last Will and Testament of Philip J. Klass
To UFOlogists who publicly criticize meâ€¦or who even think unkind thoughts about me in private, I do hereby leave and bequeath THE UFO CURSE: No matter how long you live, you will never know any more about UFOs than you know today. You will never know any more about what UFOs really are, or where they come from. You will never know any more about what the U.S. Government really knows about UFOs that you know today. As you lie on your own death-bed you will be as mystified about UFOs as you are today. And you will remember this curse.