What made everyone go wild for 'the dress' that looked two different colors last year? Why do so many people love Carpool Karaoke? And why do some stories like this crazy popular gem about those annoying drivers who wait to the last second to merge from my Inc.com colleague Minda Zetlin end up breaking the internet?

You might think these three very different examples of viral success demand very different explanations -- maybe one is about bafflement, the other about talent, and the last about pet peeves, for example -- but according to classic sociological research recently dug up by Highrise founder Nathan Kontny on his blog there's really only one underlying formula that makes something super interesting and therefore super shareable.

"What seems to be X is in reality non-x."

The research, from Northern Illinois University sociology professor Murray Davis, is from all the way back in 1971, well before the internet was even a gleam in its creator's eye, but apparently the recipe for catching other people's attention hasn't changed much over the decades. It's also deceptively simple. Davis explained:

All of the interesting propositions I examined were easily translatable into the form: 'What seems to be X is in reality non-x'.

An audience finds a proposition 'interesting' not because it tells them some truth they thought they already knew, but instead because it tells them some truth they thought they already knew was wrong.

Or, as Kontny sums up the findings: "We crave ideas that attack what we had taken for granted."

Undermining conventional wisdom will make you popular.

In these crazy, polarized times, politics seems to be the obvious exception. In that arena, confirming existing biases and preaching to the choir seem to do sadly well, but Davis's succinct formula predicts popularity surprisingly well in other contexts.

"The dress" was so interesting because it challenged a fundamental truth we all take for granted -- that a given object is only a single color, and that we all perceive that color approximately the same. Everyone expects car singing to be terrible and celebrities to hang out in swish clubs not rush hour traffic, thus the charm of Carpool Karaoke.

And finally, I can attest that Davis's formula very often holds true for written content as well. Minda's column was shared so often, I suspect, because it said selfish last minute mergers actually speed up traffic (I still don't believe it!). My most popular recent post talks about how Uber's new CEO admitted to being terrified -- or to put it as Davis might have, top CEOs seem endlessly confident, but they're actually not confident (or, interpreted differently: fear seems like a weakness, but is actually a strength).

Does this formula explain every viral success ever? No, certainly we sometimes share things because they reaffirm our belief in the human spirit, boil our blood, teach us something valuable, or are unbelievably cute, but this dead simple expression of what people usually find interesting still explains quite a lot. (Check out Kontny's post for plenty more examples.)

So next time you're wondering how to create more viral content, ask yourself this simple question: what conventional wisdom can I question or everyday belief can I overturn? What unlikely pairing can I make that will jar people's expectations?

None of us bats 1.000 online, but understanding this straightforward formula can dramatically increase your odds of producing something hugely popular.