If I have accepted the invitation to speak here, it was not out of vanity alone. I thought I was invited because somebody else did not come, and the invitation to come here reminded me of a story some of you may know. It goes as follows: There was a toastmaster in either England or the United States who was to introduce some very illustrious and very witty person, and that person was prevented from coming. So the toastmaster said "Ladies and gentlemen, tonight it was to be my signal honour to introduce to you one of the most celebrated wits of our time. Unfortunately he couldn't come, so I brought two halfwits instead."