Yes, this time you have lighted upon something formidable. I can picture to myself that unknown speaker; he is probably an assistant of the guest of honour, perhaps already a junior lecturer himself, a young man with the brightest prospects. I will press him and ask whether he is sure he did not perceive some feeling in himself antagonistic to the demand that he should pay honour to his chief. A nice fuss there is! He becomes impatient and suddenly bursts out at me: “Look here, enough of this cross-examination, or I’ll make myself disagreeable! You will ruin my career with your suspicions. I simply said “_aufstossen_” instead of “_anstossen_,” because I’d already said “_auf_” twice before it. It’s the thing that Meringer calls a perseveration, and there’s nothing else to be read into it. Do you understand me? That’s enough.” H’m, this is a startling reaction, a truly energetic repudiation. I see that there is nothing more to be done with the young man, but I think to myself that he betrays a strong personal interest in making out that his slip has no meaning. You will perhaps agree too that he has no right to become so uncivil over a purely theoretical investigation, but after all, you will think, he must know what he wanted to say and what not. O, so he must? That is perhaps still open to question. Now you think you have me in a trap. “So that is your technique,” I hear you say. “When the person who commits a slip gives an explanation which fits your views then you declare him to be the final authority on the subject. He says so himself! But if what he says does not suit your book, then you suddenly assert that what he says does not count, one need not believe it.” Certainly that is so. But I can give you another instance of a similarly monstrous procedure. When an accused man confesses to a deed the judge believes him, but when he denies it the judge does not believe him. Were it otherwise the law could not be administered, and in spite of occasional miscarriages you will admit that the system, on the whole, works well. “Well, but are you a judge, and is the person who commits a slip to be accused before you? Is a slip of the tongue a crime?”