There's a thing on the Internet called "Rule 34," which stipulates that for anything you can imagine, there's a porn version of it. (The Post looked into this earlier this year, and found that it was basically true.) We might propose a corollary to that rule, though, dubbed Rule 2016: If you are looking to bolster a conspiracy theory, the Internet has the evidence you're looking for.

On Sunday, former New York City mayor Rudy Giuliani made an appearance on "Fox News Sunday" in which he chastised the media for not covering a rampant conspiracy theory about Hillary Clinton's health.

GIULIANI: She has an entire media empire that constantly demonizes Donald Trump and fails to point out that she hasn't had a news conference in 300 days, 200 days, 100 days, I don't know how long. Fails to point out several signs of illness by her. What you’ve got to do is go online. All you have to do —
FOX NEWS'S SHANNON BREAM: Which her campaign and other people defending her saying there's nothing factual to the claims about her health and that that's speculation at best.
GIULIANI: So, go online and put down "Hillary Clinton illness," take a look at the videos for yourself.

Rule 2016! Of course you can find conspiracy-theory videos on the Internet. Some of them are being hawked by the likes of Sean Hannity. Some, as BuzzFeed found when it did the exact search Giuliani recommended, feature dudes filming themselves in their cars. Neither end of the spectrum is particularly believable, but it can sometimes seem as if the sheer weight of the available "evidence" is enough to recommend it as being true.

In 2009, Lawrence Lessig (himself briefly a sort-of-candidate for the presidency this year) wrote an article for the New Republic titled, "Against Transparency." Lessig was addressing the availability of public information from the government, things like campaign finance data. But the point works more broadly: Data — or anecdotes — can be used to make a defamatory point quickly that more context and slower consideration would reveal as obviously false.

"To understand something — an essay, an argument, a proof of innocence — requires a certain amount of attention," Lessig wrote. "But on many issues, the average, or even rational, amount of attention given to understand many of these correlations, and their defamatory implications, is almost always less than the amount of time required. The result is a systemic misunderstanding — at least if the story is reported in a context, or in a manner, that does not neutralize such misunderstanding."

Particularly if the observer has no interest in seeing the misunderstanding corrected.

Fairleigh Dickinson conducted a survey at the tail end of the primary season asking people if they believed in a number of conspiracy theories. Democrats were less likely to believe in the six theories that were presented than were Republicans — but no group was more likely to believe more of them than Trump backers.

Forty percent of Trump backers said it was "definitely true" that President Obama is "hiding important information about his background and early life." Fully half said that Hillary Clinton knew about the Benghazi attack in advance and let it happen.

Sometimes Donald Trump and his supporters simply imagine that evidence exists for claims that they are making. At other times, they use bits and pieces from around the Web to make the case.

Remember when Donald Trump said that the man who charged the stage during an event in Ohio earlier this year had "ties to ISIS"? He eventually cited an edited YouTube video as his evidence, saying: "What do I know about it? All I know is what's on the Internet."

On the Internet, you can still find people defending the idea that the man who charged the stage was actually linked to the Islamic State. You can uncover theories to bolster any argument, up to and including the argument that all of the polls are wrong and Trump is actually winning. Some of this isolation of data happens now and has happened at the conservative clearinghouse Breitbart.com — the head of which recently resigned to take over Trump's campaign.

The Giuliani health thing works the same way. Lots of little bits and pieces from across the Web are strung together to create a picture of something that isn't true. (Clinton released a health assessment from her internist last year and followed that up last week with statements addressing the most recent conspiracies.) Especially for those inclined to believe the worst about Clinton, it is easier to accept the argument that she's ailing than it is to evaluate it. (Incidentally, it's not clear what political value lies in the debunked claim, except, it seems, in Giuliani's argument that once again the media is biased.) The Internet also creates little pockets of agreement where conspiracy theories can take root and flourish.

How easy is it to find a conspiracy theory on the Internet? Well, here's one I found without too much effort.

Using Rudy Giuliani's standard, I invite you to take a look at the evidence for yourself.