Video claims “just a single question” is all it takes to catch an unfaithful boyfriend or girlfriend in a lie, but it may have other consequences.

At times, Japan may feel like a country of limitless romance. It’s a country where there’s a wedding chapel offering a Final Fantasy ceremony, and even a luckless Internet writer can find love in the most unorthodox way.

And yet, just like in any country where two people can fall in love, sometimes one of those people decides they’d like to get a little loving on the side, as surveys have shown. So with the possibility of infidelity being part of playing the game of love in Japan, a recent video from Japanese Twitter user @xOTSK has been getting attention, because he claims to know a way to find out if your partner has been cheating on you “with just a single question” (though it actually ends up being two questions).

Technically, it’s a technique to see if someone is lying, but he says it’s especially useful in tripping up cheaters who’re trying to feed you a feast of falsehoods. “Try this out when you’re thinking ‘I think my lover cheated on me yesterday,’” he says, before going into the method’s specifics:

First, ask ‘What did you do yesterday?’ Have them tell you the specifics. ‘What did you eat for breakfast?’ ‘How did you get to where you went?’ ‘Who did you see?’ ‘What did you talk about?’

They might answer something like ‘I had toast for breakfast, then I walked to the station and met up with so-and-so. We took the train to Shibuya and sang karaoke, then we went shopping at the 109 department store and ate dinner at a casual restaurant, and then I went home.’ And that’s the moment when you can expose their lies! There’s a single, all-powerful question you hit them with then.”

So what’s @xOTSK’s sure-fire lie-detector question?

“Ask them, ‘OK, now can you say all that in reverse?’”

@xOTSK’s logic is that when people lie, they’re making things up, and when they have to lie repeatedly in succession, they start using all of their mental capacity thinking of the next lie. That plays havoc with their short-term memory regarding the lies they’ve already said, and so when they suddenly have to shift into reverse and repeat their made-up story from end to beginning, they can’t remember, or to put it more accurately, repeat the falsified specifics.

“This is a technique the FBI uses in interrogations” @xOTSK goes on to say. “It’s a reliable way of exposing lies.” In just over a day, his video racked up over 1.75 million views, with impressed individuals leaving comments such as:

“This is so totally useful! I’m gonna try it out at work tomorrow.”
“I tried this on my friends, and they couldn’t say their lies backwards. It gave me goosebumps.”
“My friend’s boyfriend couldn’t tell his story backwards either.”

However, not everyone is convinced that @xOTSK’s method opens a window into the deceitful darkness that lurks in people’s hearts. For starters, it makes the assumption that everyone who’s not hiding something can instantly call up the specifics of everything they did yesterday and effortlessly spit them back in reverse. “I can’t even remember what I ate for breakfast yesterday,” said one doubter.

▼ We can’t either…but we hope it was steak.

It’s not just the potential for false positives that makes the test unreliable, either. Commenters provided simple examples that would be airtight lies against the test, such as “I had the day off, so I just loafed around at home and spent the whole day playing this one video game.” And just like some people who’re telling the truth can’t rearrange the facts in the opposite order that they happened, some skilled liars can do it with ease. “My parents used to try @xOTSK’s trick on me when I was a kid,” said one experienced trickster, “so I trained myself to speak slowly and remember everything I was saying before moving on to the next lie.”

There’s also the fact that in order to detect a lie, either correctly or not, the person administering the test has to remember everything the person they’re questioning just told them for the first time. If you can’t remember the specifics and sequence of the six or seven details of your partner’s report on their activities the previous day, you won’t have anything to check it against, so the test can easily be defeated by any liar just as long as their mnemonic capacity (even if diminished from thinking up lies) is greater than yours.

But perhaps the greatest flaw with @xOTSK’s test is that no matter what, it’ll end in an unhappy situation for the person who asks the questions. Possibility 1 is that your partner fails the test and you end up thinking they’re lying and cheating on you (even if, as outlined above, that might not be the case). But what’s possibility 2? They pass the test, and at the same time as you’re breathing a sigh of relief at their integrity, they’re grinding their teeth in annoyance at you for interrogating them using what was presented to you as a strategy to catch criminals.

▼ Romantic?

And that’s even assuming they deign to play along with the cops-and-crooks bit in the first place. “If someone said ‘Tell me, specifically, everything you did yesterday,’ I’d say ‘What? No, that’s a pain’ and end things right there,’” explained one commenter. Honestly, it’s a pretty easy way to kill anyone’s desire to have a conversation or spend any time at all with you, which might lead to them deciding they’d rather date someone else even if they haven’t been cheating.

So if @xOTSK’s test isn’t the epitome of effectiveness, how are you supposed to catch someone who’s cheating? Memorize the sounds of the trains that go by their house in order to track their movements during phone calls? Wait for Japan’s emergency earthquake warning system to expose their duplicity?

If I can offer a bold suggestion, if you think your partner is cheating on you, ask them “Are you cheating on me?” If they say “No” and you believe them, great! Problem solved. And if they say “No” and you don’t believe them? Well, then the relationship is pretty much over already, isn’t it?

Source: Twitter/@xOTSK via Hachima Kiko
Top image: Pakutaso
Insert images: Pakutaso (1, 2, 3)

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