“It Takes One to Know One” Isn’t Insight—It’s a Trap. Here’s How I Learnt to Defuse It

You’ve seen it happen. Someone calls out a liar, and the liar snaps back: “Takes one to know one.” A partner accuses the other of selfishness, and they hiss: “You’re just describing yourself.” A colleague labels your ambition as “ruthless,” and when you challenge them? “Mate, it takes one to know one.”

I’ve been on the receiving end of this phrase more times than I care to admit. At first, it stung—Was I the problem?—but lately, I’ve realised something:

This phrase isn’t wisdom. It’s a cop-out. A psychological smoke bomb.

Let me explain why.

Here’s the truth, the moment they say it, they've already lost.

When someone hits you with “it takes one to know one,” you feel that irritation rise. It feels unfair. Unjust. You start questioning your own character: “Wait, am I actually like them?”

But here’s what’s really happening:

They’re not engaging. They’re deflecting.

This phrase isn’t about truth—it’s about silencing truth.

It’s a script-flipping, water-muddying tactic designed to make you doubt your credibility so they never have to face their own behaviour. Classic gaslighting? You bet.

Let me get raw with you. I’ve always prided myself on working with relentless focus. But last year, a colleague called me “obsessed with success and money” during a battle of opinions ;) When I asked why they’d say that, they smirked: “Takes one to know one.”

Translation? “I don’t want to explain myself. I just want you to shut up.”

That moment taught me something psychologists call defensive projection. It’s not insight. It’s insecurity in a cheap suit.

When someone uses this line, two things are always happening:

1. They feel exposed. Your criticism hit a nerve. Their ego can’t handle it, so they retaliate.
2. They’re avoiding accountability. By implying you’re the problem, they dodge responsibility.

I dug into research and found studies showing people who deflect blame (instead of reflecting) are three times more likely to repeat toxic behaviours. Why? Because deflection is a drug—it numbs the pain of growth.

But let’s address the elephant in the room: Does the phrase ever hold truth?

Sure. Sometimes. If you’re a recovering narcissist, you might spot narcissism faster. But 90% of the time? If you’re hearing this phrase, it’s not philosophy—it’s a lazy insult dressed in a three-piece suit.

Why They Really Use It:

Fear in Disguise; The reason people spit this phrase out? They’re scared.

Scared of introspection. Scared of being “found out.”

Scared of the work it takes to change.

So they weaponise your words and throw them back at you.

It’s emotional jiu-jitsu

using your momentum against you.

But ask yourself: When was the last time someone said this phrase calmly? Kindly? Never. It’s always snarled in anger, hissed in fear, or coated in shame. That’s your clue.

I would suggest: Don’t play their game. Here’s the script I’ve honed after years of trial and error:

1. Stay calm. Deflectors thrive on chaos. Deny them the drama.
2. Ask questions. “What makes you say that?” Force them to explain their logic. Spoiler: They’ll crumble.
3. Refocus. “Let’s stick to the issue: your actions, not mine.” Watch them squirm.

If they double down? Walk away. You can’t reason with someone who uses clichés as armour.

Let’s be real—I’ve used this phrase before. We all have. But the older I get, the more I see it for what it is: a distraction.

Criticism isn’t a mirror. It’s a spotlight. And when someone tries to swing that spotlight back on you? It’s because they can’t bear the heat.

So next time someone says, “It takes one to know one,” smile and say: “Nice try. Now, about your behaviour…”

Tell me about a time this phrase was weaponised against you. Did you spot the deflection? Let’s unpack it—no smoke bombs, just truth.