10 signs someone is a know-it-all who vastly overestimates their intelligence

Socrates famously said, “All I know is that I know nothing.”

Unfortunately, some people didn’t get the memo. They suffer from the so-called Dunning-Kruger effect, which means that they vastly overestimate their intelligence and struggle to admit the limits of their knowledge.


Let’s have a look at the 10 signs that you’re dealing with a know-it-all.

1) They love to point out every single mistake

Have you ever talked to those people on the internet who catch every grammatical mistake and think it’s the most effective way to undermine your argument?

“Actually, there are two ms in ‘accommodate’, so… your point about environmentally sustainable accommodation holds no ground. You can’t even spell.”

Yes, those.

A know-it-all person is precisely like that. They point their finger toward every error they come across, taking great pleasure in making others feel silly.

Which brings us to…

2) They wave away opposing points of view as if they didn’t matter

Their truth is the only truth that counts.

The problem with know-it-alls is that they don’t have the humility to admit the world’s much larger and more complicated than they could ever imagine.

They operate within definitions, hard facts, and deeply ingrained beliefs – even if delusional –, thinking it gives them control over what happens.

This means that opposing points of view simply have no place in their world. They either wave them away like an annoying fly or belittle you for thinking differently.

In a discussion, they don’t view you as an equal. Instead, they think of all the ways they could “enlighten” or “educate” you, converting you to their side of the narrative.

3) They react to a lack of knowledge with shock or contempt

“What, you haven’t read 1984? Are you kidding?”

“π is equal to 3.14159. Everyone knows that.”

“Antananarivo is obviously the capital of Madagascar. Duh.”

Wisdom lies in acknowledging that truth is complex, that people don’t always get the same educational opportunities, and that intelligence encompasses multiple different spheres, from emotional self-regulation to logic.

But know-it-alls aren’t very wise. That’s the point (duh).

They tie their self-worth to how clever they are or how much information they’ve accumulated, which means they measure others by the same yardstick.

When you don’t know something, they’re either absolutely shocked because they can’t wrap their head around the fact that everyone’s background differs, or they use it as an opportunity to feel better about themselves.

Related: These 8 phrases indicate that someone is genuinely interested in you

4) Their own lack of knowledge is a source of embarrassment

I once had a classmate who never admitted he didn’t know something.

Instead, he would nod as if he knew exactly what you were talking about. He embellished things, came up with non-committal answers that didn’t betray nor confirmed his ignorance, and swiftly changed the topic if there was no other alternative.

He was embarrassed to admit his head wasn’t the Great Library of Alexandria.

But the thing is, we all lack in certain areas. The world of academia is so very specialized that it’s literally impossible to become a pro at every single subject.

When in doubt, ask. As the famous proverb goes, “He who asks a question is a fool for five minutes; he who does not ask a question remains a fool forever.”

5) They don’t ask for advice – even if they need it

Speaking of asking for stuff, a know-it-all is always hesitant to ask for advice because it goes against their assumptions about who they are as a person.

“I can do it myself,” they think.

“I don’t need anyone,” they think.

“It’s supposed to be my decision and my decision only,” they think.

But consulting your options with others before making a decision is actually very effective. In fact, research shows that being open to guidance adds texture and nuance to our thinking, helping us overcome cognitive bias and faulty logic.

Unfortunately, people who overestimate their intelligence also tend to underestimate the intelligence of others, making them feel like their advice is the only one worth considering.

6) They love to give unsolicited advice

Naturally, the other side of the coin is giving too much advice too often, especially when unprompted. A know-it-all loves to view your problems as scientific experiments that are to be dissected, pulling everything apart and overanalyzing each step of the process.

The worst bit? They go on to tell you exactly what you should do and in which order. When you don’t entirely agree, they dig their heels in and keep trying to convince you why their plan is the only viable solution.

Of course, this means there’s zero emotional support from their side. All that matters to them is the correct solution, not whose feelings get hurt.

Before you know it, one small complaint about your boss has turned into a one-hour fight with your friend because they just can’t understand why you won’t follow their directions and speak to HR.


7) Arguing is their favorite hobby

Know-it-alls tend to be masters at arguing. Rhetoric is where they excel, and if twisting your words were a competition, it’s safe to say they’d win first place.

Remember that classmate I had? Yep, he also loved to argue.

Especially when the whole class was against him, the teacher included. While he felt like he was talking to a group of children whose thinking simply wasn’t as elevated as his, we all agreed his rigid mindset was primarily at fault.

He chose a side and fought for it with all his might, even if he realized he wasn’t entirely right halfway through the argument. There’s no turning back now! he probably thought. Got to win!

But true wisdom is about admitting an error and explaining your thinking process, not winning some theoretical battle.

8) They’re terrified of competition

Sometimes, a know-it-all recognizes someone else’s brilliance. And it scares them to no end.

Have you ever met a smart cookie who detested every single intelligent person in a 5-mile radius for seemingly no reason? 

They might blame it on their personality – “he’s just such a hypocrite” –, their vibe – “there’s something off about her, you know?” –, or their career – “I never listen to journalists, they have no clue what they’re talking about” –, but at the end of the day, it always boils down to fear.

They’re scared of being confronted and losing. Know-it-alls much prefer to move amongst people who seem to pose no threat to their ego, in an environment where their knowledge and skills can remain in the spotlight.

9) They prefer monologues over dialogues

When a know-it-all is comfortable – i.e., feels unthreatened –, they enjoy giving long speeches instead of having actual conversations.

They just love the sound of their own voice. They tend to treat the other person more as a member of the audience rather than an equal actor on stage, and before you know it, half an hour has passed and you haven’t even uttered one word.

People who overestimate their intelligence enjoy humoring themselves, explaining everything out loud, and getting tangled up in their own feeling of importance.

Unfortunately, you’re just there to witness the one-man performance and ask the occasional question to prompt another monologue.

As a result, talking to a know-it-all can get very boring.

10) Everything is “easy”

Finally, a glaring red flag that someone is a know-it-all is their tendency to think everything’s easy and completely doable.

“Ah, that math test? That was a breeze!”

“Working as a nurse? I mean, how hard can it be?”

“If I wanted to write a bestselling book, I would. But I don’t!”

This brings us back to the Dunning-Kruger effect, wherein someone’s limited knowledge makes them feel like they already know everything there is to know.

The only missing ingredient is their desire to make it happen. But if they wanted to, they could!

Unfortunately, taking on tasks you’re not equipped for and overestimating how well you’ll do can lead to some very unfortunate consequences – namely, embarrassing yourself.

Instead, always aim to remain on the other side of the spectrum. I’m not saying you should underestimate your abilities, but if you approach every challenge with just a tiny bit of humility, you’re bound to either perform as expected or surpass everyone’s expectations.

As the author Ralph W. Sockman once said:

True humility is intelligent self-respect which keeps us from thinking too highly or too meanly of ourselves. It makes us modest by reminding us how far we have come short of what we can be.”

Denisa Cerna

Hi! I’m a fiction author and a non-fiction freelance writer with a passion for personal development, mental health, and all things psychology. I have a graduate degree in Comparative Literature MA and I spend most of my time reading, travelling, and – shocker – writing. I’m always on a quest to better understand the inner workings of the human mind and I love sharing my insights with the world. If any of my articles change your life for the better… mission accomplished.
Get in touch at denisacerna.writing@gmail.com or find me on LinkedIn.

10 ways to show your intelligence without talking about your IQ

Mature people never do these 14 things in relationships