"Are you going to tell me," asked Herman, more carefully still, "that this--gentleman--is the one who is supposed to remember the Earth itself? The rocks and minerals and so on?" "Yes, exactly. I was about to tell you--" "And that the planet has disappeared because he has amnesia?" Herman demanded on a rising note. Secundus beamed. "Concisely expressed. I myself, being, so to speak, saturated with the thoughts and habits of human beings, who are, you must admit, a garrulous race, could not--" "Oh, no!" said Herman. "Oh, yes," Secundus corrected. "I can understand that the idea is difficult for you to accept, since you naturally believe that you yourself have a real existence, or, to be more precise, that you belong to the world of phenomena as opposed to that of noumena." He beamed. "Now I will be silent, a considerable task for me, and let you ask questions." Herman fought a successful battle with his impulse to stand Up and shout "To hell with it!" He had been through a great deal, but he was a serious and realistic young man. He set himself to think the problem through logically. If, as seemed more than probable, Secundus, Primus, Hairy, Four-eyes, and this whole Alice-in-Wonderland situation existed only as his hallucinations, then it did not matter much whether he took them seriously or not. If they were real, then he wasn't, and vice versa. It didn't make any difference which was which. He relaxed deliberately and folded his hands against his abdomen. "Let me see if I can get this clear," he said. "I'm a noumenon, not a phenomenon. In cruder terms, I exist only in your mind. Is that true?" Secundus beamed. "Correct." "If _you_ got amnesia, I and the rest of the human race would disappear." Secundus looked worried, "That is also correct, and if that should happen, you will readily understand that we _would_ be in difficulty. The situation is extremely--But pardon me. I had promised to be silent except when answering questions." "This is the part I fail to understand, Mr. Secundus. I gather that you brought me here to treat Mr. Primus. Now, if I exist as a thought in your mind, you necessarily know everything I know. Why don't you treat him yourself?" Secundus shook his head disapprovingly. "Oh, no, Dr. Raye, that is not the case at all. It cannot be said that I _know_ everything that you know; rather we should say that I _remember_ you. In other words, that I maintain your existence by an act of memory. The two functions, knowledge and memory, are not identical, although, of course, the second cannot be considered to exist without the first. But before we become entangled in our own terms, I should perhaps remind you that when I employ the word 'memory' I am only making use of a convenient approximation. Perhaps it would be helpful to say that my memory is comparable to the structure-memory of a living organism, although that, too, has certain semantic disadvantages. Were you about to make a remark, Doctor?"