People share the 18 things that are a 'subtle sign' someone is really smart
"They effortlessly communicate complex concepts in a simple way."

Albert Einstein
One of the strangest things about being human is that people of lesser intelligence tend to overestimate how smart they are and people who are highly intelligent tend to underestimate how smart they are.
This is called the Dunning-Kruger effect and it’s proven every time you log onto Facebook and see someone from high school who thinks they know more about vaccines than a doctor.
The interesting thing is that even though people are poor judges of their own smarts, we’ve evolved to be pretty good at judging the intelligence of others.
“Such findings imply that, in order to be adaptive, first impressions of personality or social characteristics should be accurate,” a study published in the journal Intelligence says. “There is accumulating evidence that this is indeed the case—at least to some extent—for traits such as intelligence extraversion, conscientiousness, openness, and narcissism, and even for characteristics such as sexual orientation, political ideology, or antigay prejudice.”
Reddit user Gisgiii posed a question to the AskReddit subforum: “What is a subtle sign that someone is really intelligent?”
The answers painted a clear picture of how smart people behave: They tend to be great communicators who understand their audience and are more concerned with getting things right than being right.
Here are 18 of the best answers.
1. They draw wisdom from multiple sources.
"They draw wisdom from multiple sources. Wait but that might be more wise than intelligent... But I guess those two tend to be seen together a lot," — Puzzlehead-Engineer
2. They know their audience.
"They can switch up the way they talk to match the person they're talking to without sounding condescending. They listen to how others learn and explain it in that person's language of understanding," — Wynonna99
3. They develop a keen sense for their job.
"I used to work with a doctor - Tom Howard - and the day I realized he was a genius was the time he guessed every single condition a patient of mine had based on minute pieces of information about him," — Yodei_Mon
4. Curiosity.
"They are curious about everything. To be intelligent you need to be knowledgeable and you can't be knowledgeable if you are never curious," — soup54461
5. They're great at conveying ideas.
"When they explain something they make you feel intelligent," — gwoshmi
6. Considerate questions.
"They spend time thinking before asking a question," — ParkMan73
7. They make hard ideas simple.
"They effortlessly communicate complex concepts in a simple way," — joculator
8. They know what they don't know.
"They know when their knowledge ends and say something to the extent of 'i don't know and anything else i say on this topic is ignorant speculation,'" — blutoboy
9. They ask great questions.
"They can ask really good questions."
"Edit: to anyone not understanding what mean, I’m talking about people who ask “really good questions”, not just any questions, really good ones. I don’t know how one would achieve this skill(I know I haven’t)," — milkmanbran
10. They don't pretend to know everything.
"They aren’t afraid to say they don’t know the answer to a question," — xchernx
11. They change their minds with new information.
"They admit to changing their mind about something," — FarAwayAdventure
12. They pivot well.
"They apply knowledge from one realm into a new and relevant situation," — soubestitch
13. They are open-minded.
"They can genuinely consider an idea which opposes their worldview without necessarily accepting it," — paidshill29
14. They use analogies.
"People who use analogies to explain concepts to others. It’s a form of code-switching and integrating concepts on the fly and is a clear indicator someone is both socially and conceptually intelligent," — SwimmerAutomatic2488
15. They don't argue.
"I think intelligent people are more willing to calmly debate/discuss, rather than argue. Like, you explain to them why you disagree, and they listen to you and ask further questions about your viewpoint before offering a different perspective; as opposed to an unintelligent person, who would just resort to insults when other people disagree with them," — AngelicCinnamonBun
16. They learn from mistakes.
"Admitting when they're wrong and being willing to learn from mistakes," — siyl1979
17. A sense of humor.
"Humor. I think that truly funny people are often very smart and cognizant of the different ways an idea can be humorous on several levels. They also know their audience. I think the difference between say a Jeff Foxworthy and a Dave Chappelle and a Bo Burnham is their audience and their interests," — biscuitboi967
18. A love of learning.
"They say they love learning and they learn something new every day. Then they listen more than talk," — throwingplaydough
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There's a reason why some people can perfectly copy accents, and others can't
Turns out, there's a neurodivergent link.
A woman in black long sleeve shirt stands in front of mirror.
Have you ever had that friend who goes on vacation for four days to London and comes back with a full-on Queen's English posh accent? "Oooh I left my brolly in the loo," they say, and you respond, "But you're from Colorado!" Well, there are reasons they (and many of us) do that, and usually it's on a pretty subconscious level.
It's called "accent mirroring," and it's actually quite common with people who are neurodivergent, particularly those with ADHD (Attention Deficit Hyperactivity Disorder). According Neurolaunch, the self-described "Free Mental Health Library," "Accent mirroring, also known as accent adaptation or phonetic convergence, is the tendency to unconsciously adopt the accent or speech patterns of those around us. This linguistic chameleon effect is not unique to individuals with ADHD, but it appears to be more pronounced and frequent in this population."
Essentially, when people have conversations, we're constantly "scanning" for information—not just the words we're absorbing, but the inflection and tone. "When we hear an accent, our brains automatically analyze and categorize the phonetic features, prosody, and intonation patterns," writes Neurolaunch. For most, this does result in copying the accent of the person with whom we're speaking. But those with ADHD might be more sensitive to auditory cues. This, "coupled with a reduced ability to filter out or inhibit the impulse to mimic…could potentially explain the increased tendency for accent mirroring."
While the article explains further research is needed, they distinctly state that, "Accent mirroring in individuals with ADHD often manifests as an unconscious mimicry of accents in social situations. This can range from subtle shifts in pronunciation to more noticeable changes in intonation and speech rhythm. For example, a person with ADHD might find themselves unconsciously adopting a Southern drawl when conversing with someone from Texas, even if they’ve never lived in the South themselves."
People are having their say online. On the subreddit r/ADHDWomen, a thread began: "Taking on accents is an ADHD thing?" The OP shares, "My whole life, I've picked up accents. I, myself, never noticed, but everyone around me would be like, 'Why are you talking like that??' It could be after I watched a show or movie with an accent or after I've traveled somewhere with a different accent than my 'normal.'
They continue, "Apparently, I pick it up fast, but it fades out slowly. Today... I'm scrolling Instagram, I watch a reel from a comedian couple (Darcy and Jeremy. IYKYK) about how Darcy (ADHD) picks up accents everywhere they go. It's called ADHD Mirroring??? And it's another way of masking."
(The OP is referring to Darcy Michaels and his husband Jeremy Baer, who are both touring comedians based in Canada.)
Hundreds of people on the Reddit thread alone seem to relate. One comments, "Omfg I've done this my whole life; I'll even pick up on the pauses/spaces when I'm talking to someone who is ESL—but English is my first language lol."
Sometimes, it can be a real issue for those around the chameleon. "I accidentally mimicked a waitress's weird laugh one time. As soon as she was out of earshot, my family started to reprimand me, but I was already like 'oh my god I don’t know why I did that, I feel so bad.'"
Many commenters on TikTok were shocked to find out this can be a sign of ADHD. One jokes, "Omg, yes, at a store the cashier was talking to me and she was French. She's like 'Oh are you French too? No, I'm not lol. I'm very east coast Canada."
And some people just embrace it and make it work for them. "I mirror their words or phrase! I’m 30. I realized I start calling everyone sweetie cause my manager does & I work at coffee shop."