Sitting around the Christmas table, surrounded by family, is a joy many of us cherish.

Yet, amid the festive cheer, you may notice a pattern: familiar debates about politics, life choices, or the latest news headlines. You might hear your uncle passionately defend his opinion or your grandmother dismissively wave off a new idea.

These moments can feel frustrating, but they also reveal something profound about how our minds work as we age.

Over the years, I’ve found myself asking: why do older relatives often seem so set in their ways? And am I slowly becoming like them?

Introducing System 1 and System 2 Thinking

To answer this, let’s explore the concept of System 1 and System 2, popularized by psychologist Daniel Kahneman in Thinking, Fast and Slow.

System 1 is your brain’s autopilot. It’s fast, intuitive, emotional, and heavily influenced by habits and external stimuli. When you instantly recognize a friend’s face in a crowd or react to a car horn, that’s System 1 in action.

System 2, on the other hand, is your deliberate, logical side. It’s slower, requires effort, and engages when you solve a complex problem or challenge a deeply held belief.

The two systems work together, but System 1 is dominant most of the time. It’s easier, after all, to rely on quick judgments than to wrestle with uncomfortable questions. But here’s the catch: as we age, without intentional effort, System 1 tends to take over even more.

Why We Stay on the Surface

Picture Mark, a mid-level office worker in his late 40s. His Thursday mornings have a rhythm all their own. He starts the day with a car ride, Spotify playlist humming in the background, setting the tone for a predictable day. Arriving at the branch, he already knows the routine: tackle the biggest task first — what he calls “eating the frog.” By mid-morning, he feels accomplished, and prepared for a meeting with his regional manager, knowing that the rest of the day will be relatively chill.

During the meeting, Mark stays engaged, but his mind occasionally drifts. After all, the bulk of his work is manageable, and he can predict how long it’ll take to wrap up his tasks. Post-meeting, he books a holiday during work hours, feeling a small thrill at squeezing in a personal errand. Lunchtime arrives, and he checks the canteen menu, deciding whether to indulge in his usual choice or try something new.

By the afternoon, Mark is coasting. The flow of his day leaves little room for surprises or challenges. While this predictability offers comfort, it also keeps him locked in surface-level thinking. His work rarely pushes him to engage deeply or think critically, and as a result, his mind defaults to autopilot.

His opinions are shaped by what’s easiest to consume: catchy headlines, soundbites, and the repetitive narratives of his daily environment. Without realizing it, Mark has drifted into a pattern of shallow, reactive thinking — a mental rut that grows deeper with each passing year.

Mark isn’t inherently closed-minded; he’s simply caught in a cycle reinforcing surface-level thinking and stifling deeper exploration.

Imagine your mind as the sea:

The surface is where external forces — news, social media, daily stress — toss you around. Thoughts here are reactive, fleeting, and influenced by your environment.
Deeper down, the currents are calm and steady. This is where introspection, creativity, and deliberate thinking flow. But accessing these depths takes effort.

Most people never intentionally submerge themselves into deeper thinking. Why?

Cognitive Ease: Shallow thinking feels natural because it’s effortless.
Modern Distractions: Social media, notifications, and entertainment keep us in reaction mode.
Lack of Reflection: Few people set aside time to analyze their beliefs or question their assumptions.

This reliance on System 1 is amplified by repetitive work, predictable routines, and environments that don’t challenge us to think critically.

The Aging Brain and System 1 Dominance

As we age, several factors contribute to the growing dominance of System 1:

Cognitive Routines and Habitual Thinking: Over time, we develop mental shortcuts to handle familiar problems. While efficient, these routines reduce the need for deep thinking.
Less Exposure to New Stimuli: Younger people constantly encounter novel experiences — new schools, hobbies, and social groups. Older adults often settle into predictable patterns, leaving their brains unchallenged.
Decreased Neuroplasticity: The brain’s ability to adapt and learn slows with age. Without active engagement in challenging activities, System 2 becomes harder to access.
Comfort Zone Syndrome: Stability becomes a priority as we grow older. Engaging System 2 often requires discomfort and effort, which we instinctively avoid.
Accumulation of Biases: Decades of unexamined beliefs and experiences solidify into biases, making us more reliant on snap judgments.

Why Younger People Think Differently

Take Anna, a young student who spent a year abroad at Erasmus University Rotterdam. It was her first time truly engaging with people from neighboring countries she’d only known through stereotypes. Growing up, she assumed her country’s customs and traditions were the norm, viewing everything else as “other.”

In Rotterdam, she was struck by how different things were. She learned that they leave garbage bags on the street to be collected, a behaviour she found shocking. Others tipped garbage collectors as a token of appreciation — a gesture she never considered. She attended a birthday party where everyone paid for their food, a far cry from the all-inclusive hosting she was used to back home.

These differences forced Anna to question her preconceived notions. She realized how much of her worldview was shaped by her upbringing and how little she had challenged those assumptions. She also started recognizing the value of adapting and learning, even when it was uncomfortable.

Young people often seem sharper and more open-minded because their brains are still flexible and ready to learn. They haven’t yet built up a lifetime of habits and mental shortcuts, so they approach problems with fresh eyes.

Their daily lives — full of new experiences, challenges, and opportunities to grow — keep their minds active and curious. It’s easier for them to think deeply and critically because they’re used to questioning things and figuring out the world around them.

But this mental flexibility doesn’t last on its own. As people get older, life tends to become more predictable. If young people don’t make an effort to keep their brains engaged — by learning new things, reflecting on their thoughts, or stepping out of their comfort zones — they can fall into the same mental traps as everyone else. Over time, they start relying on shortcuts, forming habits, and sticking to the same old ways of thinking because it feels easier and safer.

Without intentionally challenging themselves, they risk becoming stuck in surface-level thinking, reacting to the world around them instead of truly understanding it. What makes young minds sharp can fade if they don’t nurture it, leading to the same kind of emotional, reactive, and biased thinking that often comes with age.

High Neuroplasticity: Their brains are still wiring and rewiring, making adaptation easier.
Constant Novelty: School, friendships, and early careers introduce challenges that force System 2 engagement.
Fewer Mental Shortcuts: Without a backlog of habits, younger people approach problems with fresh eyes.
Innate Curiosity: Curiosity drives exploration and deep thinking, something that tends to diminish with age unless actively nurtured.

Breaking Free from Surface Thinking

Contrary to the belief that brain plasticity diminishes significantly with age, research shows that older adults retain the capacity for neuroplasticity. Activities like learning new skills, exploring hobbies, or studying unfamiliar subjects can improve cognitive functions and keep System 2 active.

Here are practical ways to break free from surface thinking:

Reflection and Journaling: Writing down your thoughts fosters introspection and sharpens critical thinking. For me, free-form journaling has been transformative. I write freely, then use ChatGPT to refine and organize my ideas into polished insights with minimal effort.
Engage in Discussions: Meaningful conversations with people who challenge your views strengthen critical thinking and reduce the risk of echo chambers.
Mindfulness and Meditation: These practices slow your mind, helping you observe and reflect on your thought patterns.
Break Routines: Trying new activities, routes, or habits disrupts reliance on System 1 and keeps the brain curious.

Even monologues can be helpful — the verbal equivalent of journaling — if you have someone who will listen. However, unlike writing, they leave no lasting record unless you choose to record them.

My Go-To Journaling Method and Tips

Journaling has been my personal go-to for fostering clarity and reflection. Here’s how I do it:

Free-Form Writing: I let my thoughts flow freely, jotting down everything on my mind without worrying about grammar or structure. This raw, unfiltered process helps me uncover underlying emotions and patterns.

Refinement with ChatGPT: Once I’ve finished, I paste the raw text into ChatGPT and ask it to refine the grammar, improve readability, and organize my thoughts into a more coherent narrative.

Consistency Over Perfection: I don’t aim for flawless entries. The goal is consistency — writing a little each day keeps my mind active and reflective.

What makes journaling so effective is how it can spark deeper thinking. It’s fascinating how starting with a single question — like why it’s easier to maintain some habits over others — can lead to unexpected realizations.

This is what I call the untangling effect: tackling one concept step by step reveals connections and patterns you hadn’t considered.

This approach taps into two powerful phenomena:

Progressive Elaboration: Starting with a small idea and expanding on it as you write. Each layer you explore uncovers deeper insights, leading you to questions or perspectives you didn’t know existed.
Serendipitous Learning: Discovering unexpected insights or making connections while engaging in a seemingly unrelated activity. You might not set out to solve a complex problem, but the natural flow of thought during journaling can lead you there.

For me, journaling is like unravelling a ball of string. You start with one small thread of thought, and as you pull, you reveal the intricate web of ideas beneath. It’s a process of discovery — both of the world and yourself.

Closing Thoughts

Consider how System 1 and System 2 shape the conversations you’re having — and the ones you aren’t. Reflect on your habits and beliefs.

Are you riding the waves of surface thinking, or are you diving deep into the currents of deliberate thought?

By making small, intentional changes, you can stay curious, nimble, and open-minded no matter your age.

Thanks,
Matija