Why Does Time Feel Different?

Ask someone to remember the last year of high school. Most people can tell you specific things — a conversation, a smell, a fight, a song that was playing. Now ask them to remember a year from their mid-thirties. If they even can — if they weren’t going through something significant — the memories blur.

The year passed. They just don’t have much to show for it.

Here’s what’s happening: your brain doesn’t have an internal clock in the way you might think. It doesn’t tick off seconds. What it does is build a record of events — and your experience of how long something lasted is roughly proportional to how much record was built.

When you’re young, everything is new. Every social situation is unfamiliar. Every place you go has details you haven’t catalogued. Your brain is working hard, taking notes, filing things away. The result: a rich, dense memory that feels long when you look back on it.

When you’re older and settled into a routine — same commute, same job, same patterns — the brain stops working as hard. Nothing is new. The record is thin. The year goes by, but there’s not much to remember. When you look back, it feels short. It felt fast.

This is why people say childhood “went by so slowly” and adult life “goes by so fast.” It’s not a trick of nostalgia. It’s a documented pattern in how human memory works.

The Attention Explanation

Psychologist William James, writing in 1890, noticed that time seems to pass differently depending on what you’re doing. He wrote: “In general, a time filled with varied and interesting experiences seems short in passing, but long as we think back on it.”

The mechanism, as we understand it now:

• Your brain processes time by encoding the number of distinct events in a period
• When you’re bored, very little is happening — so few events get encoded
• When you’re engaged, a lot is happening — many events get encoded
• But the relationship flips depending on whether you’re in the moment or looking back

In the moment: Boredom feels slow because you’re waiting for events that aren’t coming. Engagement feels fast because the events are arriving and you’re processing them.

In memory: Boredom shrinks because there’s little to remember. Engagement expands because there’s a lot to remember.

The DMV is torture not just because you’re waiting, but because you’re aware of waiting. Time doesn’t just pass — you’re actively monitoring it. The clock is the only event.

The Frightening Math

Here’s the part that changes how you think about this.

If you’re 10 years old, one year is 10% of your life. It feels vast.

If you’re 50 years old, one year is 2% of your life. In relative terms, it’s five times shorter.

But more than that: by the time you’re in your mid-twenties, you’ve experienced most of the “firsts” that drive dense memory formation. First relationship. First job. First time living alone. First serious loss. After that, the density of genuinely new experiences tends to drop.

The remedy isn’t complicated: seek novelty. Learn new things. Go to places you haven’t been. Do things that force your brain to take notes. Not because life is short — but because a life of rich, varied attention creates a felt-long life in memory.

The alternative is a life that passed quickly and quietly and left very little behind.

What This Connects To

There’s a related phenomenon in how we remember pain vs. pleasure. Psychologist Daniel Kahneman found that your memory of an experience is dominated by two things: the peak intensity and how it ended — not the average over time. A painful experience that ended pleasantly is remembered as less bad than a painful experience that ended badly, even if the total pain was equal.

This means your experienced life and your remembered life are not the same thing. You live one, you carry the other. They influence each other in complicated ways.

The upshot: paying attention matters. Not just because you’ll be more present — but because attention is literally what your memory is made of.