The Psychology of First Impressions

Hey guys,
Im finally back from my Brown Summer Program! And I’ve got to say, it was great. I knew I was in for a ride, but this? I never expected it to be that great. Not only because of the friends and connections I made, but also because the things I learned in the various classes. It was a truly eye-opening experience.

And actually, this Program made me think about something:

First impressions are weird. They’re fast, mostly unconscious, and almost always way more powerful than we give them credit for. You can spend weeks proving yourself, but people will still remember how you made them feel in the first 30 seconds.

I’ve been thinking about this a lot lately, especially, especially after my time at Brown. Being in a new place, surrounded by new people, all trying to find their footing—first impressions are everywhere. Sometimes you don’t even realize you’ve already made one until the dynamic is already set.

It’s not just about being liked. It’s about being seen the way you want to be seen. That doesn’t mean being fake—it means being intentional.

The Science-y Bit (But Not Too Much)

There’s actual research behind this. Psychologists call it “thin slicing”: our brains can form surprisingly accurate impressions based on just a few seconds of interaction. Facial expressions, body language, voice tone, posture—they all hit fast and leave a mark.

We like to believe we’re logical, that we weigh all the facts before deciding what we think about someone. But truth is, our brains are busy making snap calls: trustworthy or not? Confident or awkward? Do I want to talk to this person again or keep walking?

What I’ve Noticed

When I met new people at Harvard last year, I realized how small details—eye contact, the way you enter a room, even how you respond to small talk—can shape how others relate to you later. Sometimes people would say things like, “You seemed super confident” or “I thought you were super serious”—and I’d think, Really? I was just tired and trying to remember names.

The same thing happened here at Brown. You walk into a room, meet someone in the hallway, sit down for a group discussion—and before you’ve even said much, they’ve already filed you into some mental folder.

The cool part? You can shape that folder.

A Few Things That Help

  • Posture matters. Even standing up straight with your shoulders back can make a difference. (Shoutout to Kate Clarke and power posing :-))
  • Ask real questions. Not just “Where are you from?” but “What made you choose this course?” People open up more when they feel like you’re actually curious.
  • Match the energy. If someone’s laid back, don’t blast in at 200 mph. If someone’s excited, don’t bring funeral energy. Adapting doesn’t mean changing yourself—it means being present.
  • Smile. Obvious, but still underrated.

Final Thoughts

First impressions aren’t the whole story, but they do set the tone. And while you can’t control everything, you can definetly control how you show up.

So show up with intention. With presence. With curiosity. That’s what people remember. And once the impression is made, don’t stress. Just let your actions keep writing the rest.

Thanks for stopping by!

—Filippo