Marilyn and I sat around looking at the big bills. They were the size of present-day currency, and were beautifully made, and would have passed easily except for a few things. Such as that "Series 1988" inscribed alongside the signature of Irving P. Walcourt, Secretary of the Treasury. And the Treasurer of the United States in 1988 would be Kuru Hamonoto. From the State of Hawaii, I wondered, or--? "They're no use to us at all," said Marilyn. "Unless we hold them until 1988. I was talking about security for our old age. Do you suppose--?" "You forget," I said, "that steak will run you twenty-five or thirty thousand in 1988. This is going to be a great disappointment to the members of the Friday Night Bull Session and Experimentation Society, but I fear we must explain to Solid Chuck Richards that we just cannot afford to do much business of this type." I pushed aside the money and began thinking about some of the things the youth from 1991 had told me. There were holes in my theories--a lot of holes. True, I had succeeded in building a time machine, but I could never go anyplace in it. Because time travel was possible only by traveling from one time machine to another. The amateurs of 1991, knowing from my books (I must remember to write them) that I had built a time machine in 1959, were able to make contact. Solid Chuck Richards was selected by lot from several volunteers to try the machine. I met the other members of the Society later and learned that and a number of other things from them. The reason Solid Chuck came back instead of my going forward made solid sense. I could see it now. My time machine had never existed in 1991. His had existed in 1959, or at least its parts had. I could overcome that problem--if I had the full power of the Sun for several minutes to work with, and a way to handle it. Then I could change things so that my time machine would have existed in the future.... Even the verb tenses were going wrong on me. These amateur experimenters, it seemed, were considered a bit on the crackpot side, taking such pseudo-science as mine seriously. Not knowing enough science to realize that the ideas I wrote about were impossible, as any professional scientist would have, they followed them through. They tried to get in touch with me in their time, but I wasn't available, which saved me another paradox. Suppose I had joined the Society and come back as a volunteer? But it was encouraging to know the reason I was going to be unavailable in 1991. Marilyn and I had gone on a second honeymoon--on the first commercial passenger liner to Mars. "And so," I told her, "you don't have to worry about security in your old age. Tickets to Mars must cost a few trillion dollars. We won't be poor." Marilyn was still looking at the currency of the future. "We will be," she said, "if we keep selling steak for the price of soy-bean hamburger. By the way, Ted, I wonder who that was at the window?"