Free Time and Again by Jack Finney, Paul Hecht

to work. And Einstein announced that E equals MC squared. And, God forgive us, two Japanese cities disappeared in the blink of an eye and proved he was right again.
    "I could go on; the list of Einstein's discoveries is a considerable one. But I'll skip to this: Presently he said that our ideas about time are largely mistaken. And I don't doubt for an instant that he was right once more. Because one of his final contributions not too long before he died was to prove that all his theories are unified. They're not separate but interconnected, each depending upon and confirming the others; they largely explain how the universe works, and it doesn't work as we'd thought."
    He began peeling the red cellophane strip from the little package of crackers that came with his soup, looking at me, waiting. I said, "I've read a little on what he said about time, but I can't say I really know what he meant."
    "He meant that we're mistaken in our conception of what the past, present and future really are. We think the past is gone, the future hasn't yet happened, and that only the present exists. Because the present is all we can see."
    "Well, if you pinned me down, I'd have to admit that that's how it seems to me."
    He smiled. "Of course. To me, too. It's only natural. As Einstein himself pointed out. He said we're like people in a boat without oars drifting along a winding river. Around us we see only the present. We can't see the past, back in the bends and curves behind us. But it's there."
    "Did he mean that literally, though? Or did he mean —»
    "He always meant exactly what he said. When he said light has weight, he meant that the sunlight lying on a field of wheat actually weighs several tons. And now we know — it's been measured — that it really does. He meant that the tremendous energy theoretically binding atoms together could really be released in one unimaginable burst. As it really can, a fact that has changed the course of the human race. He also meant precisely what he said about time: that the past, back there around the curves and bends, really exists. It is actually there." For maybe a dozen seconds Danziger was silent, his fingers playing with the little red cellophane strip. Then he looked up and said simply, "I am a theoretical physicist on leave here from Harvard University. And my own tiny extension of Einstein's giant theory is… that a man ought somehow to be able to step out of that boat onto the shore. And walk back to one of the bends behind us."
    I was struggling to keep a thought from showing in my eyes: that this might be an intelligently, plausibly, mildly deluded old man who'd persuaded a lot of people in New York and Washington to join him in constructing a warehouse full of fantasies. Could it possibly be that I was the only one who'd guessed? Maybe not; this morning Rossoff had made a joke — an uneasy one? — about my joining a booby hatch. I nodded thoughtfully. "Walk back how?"
    Danziger had a little soup left, and now he finished it, tipping his bowl to get the last of it, and I finished my sandwich. Then he raised his head, his eyes looked directly into mine, and I looked back into his and knew that Danziger wasn't crazy. He was eccentric, very possibly mistaken, but he was sane, and I was suddenly glad I was here. He said, "What day is this?"
    "Thursday."
    "What date?"
    "The… twenty-sixth, isn't it?"
    "You tell me."
    "The twenty-sixth."
    "What month?"
    "November."
    "And year?"
    I told him; I was smiling a little now.
    "How do you know?"
    Waiting for a reply to form itself in my mind, I sat staring across the table at Danziger's intent, bald-headed face; then I shrugged. "I don't know what you want me to say."
    "Then I'll answer for you. You know the year, the day and the month, for literally millions of reasons: because the blanket you woke up under this morning may have been at least partly synthetic; because there is probably a box in your apartment with a switch; turn that switch, and