The world’s first time traveler was just a boy who created a machine. The moment before he first switched it on, he appeared to himself as an old man.
“Don’t,” the old man said.
The boy hesitated, but he remembered how angry he was at every adult who ever tried to hold him back.
“Fuck you, old man,” he said, smiled, and hit the switch.
In an instant, he was old, standing before his younger self.
“Don’t,” he said.