What I Learned About Happiness from a Semester at Vanderbilt

This past spring semester, I had the opportunity to take one of the most eye-opening classes I have ever taken, The Psychology and Neuroscience Behind Happiness, as a part of Vanderbilt University's Talented Youth Program. I used to think that happiness was just about "feeling good" or having fun with friends, but I quickly learned it's so much deeper than that. Happiness isn't just an emotion, but something we can nurture, shape, and practice in our daily lives.

One of the most shocking ideas I learned came from Sonja Lyubomirsky's book The How of Happiness. She explains that 50% of happiness is determined by genetic factors, 10% from circumstances, and the other 40% is in our control, through our everyday choices. That number really changed the way I thought about my own happiness, that 40% proves that we. have more control over our happiness than we may have thought.

Here are 5 of the lessons that I've carried with me:

1: Happiness isn't found-it's built.

Before this class, I thought happiness was something that happened when all things went right for you. But a quote from Lyubomirsky says it best: "The key to happiness is not in changing circumstances but in changing ourselves." Research shows that our daily actions, practicing gratitude, showing kindness, and investing in our relationships, are what build lasting wellbeing. Even small habits like writing down three things you are grateful for before bed, can leave a lasting impact on your mindset.

2: Relationships matter more than anything else.

We studied what truly predicts life satisfaction, and the answer wasn’t money, success, or accomplishments. Over and over, studies prove that close, supportive relationships are the foundation of happiness. As Lyubomirsky writes, “There is no more powerful source of happiness than our relationships with other people.” Whether it’s family dinners, laughing with teammates, or spending time with friends, connection fuels joy in a way nothing else can.

3: Gratitude is a superpower.

I’ll admit, at first the gratitude exercises felt repetitive. But the more I practiced, the more I noticed how much they shifted my perspective. Gratitude doesn’t erase challenges, but it does remind you of what’s good, even on hard days. Lyubomirsky describes gratitude as “an antidote to negative emotions, a neutralizer of envy, hostility, worry, and irritation.” I started catching myself noticing little things—like the way the sunlight hits the pool during swim practice or the laughter in between tennis drills. Those small moments added up into something bigger.

4: Mindset changes everything.

One of the most powerful lessons I learned is the difference between a fixed mindset and a growth mindset. Instead of seeing failure as the end, people with a growth mindset view it as an opportunity to learn. That doesn’t just apply to academics—it’s also about how we see ourselves, our goals, and even our happiness. Lyubomirsky reminds us that “the pursuit of happiness is a marathon, not a sprint.” It’s about progress, not perfection, and that shift in perspective makes all the difference.

5: Happiness is contagious.

This one stuck with me the most: when we practice kindness, gratitude, and positivity, it doesn’t just change us—it impacts the people around us. Smiling at a stranger, cheering on a teammate, or encouraging a friend can ripple out in ways we’ll never fully see. “When we express gratitude and kindness, we strengthen our bonds to others,” Lyubomirsky writes, and that ripple of connection multiplies happiness for everyone involved.

Looking back on the semester, I realize that happiness isn’t a destination—it’s a practice. It’s something we can choose to cultivate every day through gratitude, connection, and kindness. Positive psychology didn’t just teach me theories; it gave me tools to live with more purpose and joy.

If there’s one thing I’d share from this experience, it’s this: happiness isn’t about chasing what’s next—it’s about noticing what’s already here. And with 40% of it in our control, every day is a chance to build it.