The yard sale was one of those haphazard affairs, full of the kind of junk that no one in their right mind would actually take, damaged or torn or merely out of the realms of taste altogether. This is a powerful camouflage for the good stuff, and any experienced bargain hunter will tell you that the larger a morass of hand-me-downs and chipped Formica, the better a prize underneath.

I once found an a James Deakin and Sons egg timer amongst some horribly tarnished flatware; it clocked in at three minutes and forty five seconds, which says something about how long it took to boil an egg in 1903. Another such garage sale earned me a Railroad-approved BW Rageon pocket watch, which only took a bit of polish to look the same way it did in 1927. So when I unearthed the device from under a seriously disturbing collection of polyester sweaters, I knew it was something to treasure. I just didn’t know what.

“It’s a time machine.” A portly fellow in dark socks and sandals noticed me handling the thing, careful not to nudge the knobs. “It requires six ‘D’ batteries.”

“Pull the other one,” I said. It didn’t look like a time machine, but it didn’t look like anything else, either.

“No, seriously. It’s a time machine. I built it. Used it, even.”

“Oh? What’s the future like?”

The man laughed and regarded me like a retarded child. “You can’t go into the future! It hasn’t happened yet! Just the past. But you can go in the past all you want.”

“Hold up. You can go in the past with this? Change what’s happened? Isn’t that, I dunno, dangerous? Kill a butterfly, change the world, that sort of thing?”

The man huffed. “Nonsense. The universe is not so poorly designed. If you go back in time with the intention of changing things, one of two things is going to happen. One, you’ll be totally ineffectual, and people won’t notice you or heed you, and it won’t make a damn bit of difference whether you were there or not.”

“What’s the other?”

The man’s eyes and voice suddenly went cold. “People do notice you. And you end up being the cause of the very thing you were trying to prevent. You end up destroying the one you meant to save.” He was quiet, and reached out to touch the device in my hand, but thought better of it. “I’ve failed too many times. It doesn’t make any difference. This cost me thousands of dollars and years of my life, but I’ll give it to you for five bucks if you if you just take it away and never bring it back.”

“I don’t understand,” I said.

He looked up at me, his face flushed. He motioned blindly to his yard, strewn with trivial remnants from a life, someone’s life, priced at a bargain. “I’m selling everything else that reminds me of her. They never belonged to me, anyway. I shouldn’t keep what isn’t mine. The universe won’t let me. Five dollars on that there time machine, my final offer.”

I took it, as well as 1951 “Cort” model Seth Thomas with an alarm that still worked. On the drive home, I thought about the man’s words when I asked him one more time whether or not you could use his machine to change events.

“The present is unavoidable,” he said. “It’s best not to think about it.”