About two years ago, a Redditor named u/RBradbury1920 posted to r/LegalAdvice with a question.

A few people in the thread agreed that RBradbury1920 might just be sleepwalking.

But Dr. Tom Scammell, a director at The Sleep Disorders Clinic at Boston's Beth Israel Deaconess Medical Center, pooh-poohed that idea.

"Writing would be an unusual thing to happen, because writing is a very high-level cognitive function," he says. "... to see fully-formed and good-looking sentences like 'Our landlord isn't letting me talk to you but it's important we do,' that's pretty sophisticated."

On the other hand, Ken Roach, who is an engineer but not a sleep expert, has a different theory. He was up late one night browsing Reddit when he came across RBradbury1920's post.

The legal advice subreddit can often contain people with an undiagnosed mental illness, he said. Sometimes they'll say they're being followed, or that the FBI put a tracking bug in their arm, for example.

But RBradbury1920's past posts didn't seem like they were suffering from something like that, said Roach.

"But one thing — there was a post where they were asking in an interior design subreddit about how to fit a desk and a bed into a really, really narrow apartment that they were moving into, that didn't have any windows," he said. "... That got me thinking. Gosh, an apartment in Boston, with no windows. Of course they're hallucinating. Their landlord is not coming in and writing notes. But why are they hallucinating?"

RBradbury1920's post reminded Roach of a time where he nearly inadvertently killed himself, his wife and their dog after leaving the stove on in their liveabord — causing deadly carbon monoxide to flood the boat. Had he not opened a window, things could have been much worse.

So he posts in the thread.

Turns out RBradbury1920 was experiencing symptoms of carbon monoxide poisoning, like headaches. They posted an update.

RBradbury1920 declined to comment for this story, so we don't have a way of confirming it fully.

So was it all made up? Are the username — RBradbury1920 — and the particulars of this story just sly nods to Ray Bradbury's "Fahrenheit 451?" Is it a well-disguised PSA for making sure you have a carbon monoxide detector in your house?

Deborah Blum, a Redditor who is the director of the Knight Science Journalism Program at MIT, and the author of The Poisoner's Handbook, says the carbon monoxide explanation fits. When asked about the symptoms of low-grade carbon monoxide poisoning, Blum explains, "You might get headaches, you might feel a little groggier than usual. And depending on the chronic exposure, you can even become mentally-off, cognitively-impaired in some ways." And Blum adds that, because carbon monoxide poisoning involves oxygen deprivation to the brain, it is possible to hallucinate.

So Blum is not swayed by any conspiracy theories about the post. "I'm not all creeped off by the Ray Bradbury part of it," she says. "I mean, Ray Bradbury wrote some really interesting, troubling stories. I wasn't thinking just of 'Fahrenheit 451,' but I was thinking of 'Something Wicked This Way Comes.' But Ray Bradbury's science was absolutely grounded. So I think, if you could say nothing else, you could say he's love the story."

And what does Ken Roach think? How do we know he and RBradbury1920 aren't the same person?

"I suppose you can't. I'd like to think that, if I was, there would be more drama — that there would be a first, second and third act," he says. "There would be a hero's journey. Instead there's just me and this person out there with a poorly ventilated bedroom."

An important, real PSA for this post: Carbon monoxide detectors are pretty cheap and easy to install. In some states and municipalities, landlords must provide working detectors for every level of the dwelling. Check your local and state laws.

Thanks to Redditor u/MXLXTXV for this week's artwork, titled "Demon."

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