Why Does Time Feel Like It Speeds Up As You Get Older?

A summer when you were nine lasted forever. The weeks before school ended felt geological. July was an entire era.

You are now older. A year goes by faster than that summer did. You can feel it accelerating. The thought is mildly alarming.

This is real, it is nearly universal, and it has a surprisingly clear explanation — one that says something important about how you should choose to spend your time.

William James Noticed It First

In 1890, the psychologist William James wrote in Principles of Psychology:

“The days and weeks smooth themselves out in recollection to contentless units, and the years grow hollow and collapse.”

He had no mechanism to explain it. He just noticed what everyone notices — that lived time and remembered time diverge, and the divergence grows with age.

The question James didn’t answer: why?

The Ratio Hypothesis

The most intuitive answer was offered by the Dutch psychologist Douwe Draaisma in his 2004 book Why Life Speeds Up As You Get Older.

When you are five years old, one year represents 20% of your entire life. It is proportionally enormous. When you are fifty, one year is 2% of your life. By sheer ratio, it is smaller.

This is sometimes called the logarithmic time hypothesis — your subjective experience of duration is proportional not to absolute time but to your total accumulated experience. A year at age twenty-five is to a year at age five roughly what a minute is to ten minutes. Same absolute duration, radically different felt weight.

This explains the general trend. But it doesn’t fully explain the mechanism — why should ratio affect experience?

The Memory Landmark Theory

The more specific and better-supported explanation involves how the brain encodes time through memory.

Your sense of how long a period “was” comes almost entirely from retrospective reconstruction. When you try to assess how long last summer was, you’re not accessing a reliable internal clock. You’re accessing your memories of that period — how many distinct, distinguishable episodes you can retrieve.

The key insight: novelty creates landmarks. New experiences are encoded more distinctly by the hippocampus than routine ones. The first day in a new city generates dozens of separate, retrievable memories. The fiftieth day in the same city, following the same commute, generates almost none.

When you look back on a novel period, your memory is rich with distinct events. The reconstruction feels long. When you look back on routine, the memories blur together — or aren’t there at all — and the reconstruction feels short.

Childhood is almost entirely novelty. Everything is new — new school, new friends, new body, new social rules, new skills. Every summer contained dozens of firsts. The hippocampus was running hot.

Adulthood settles into patterns. You know your job, your city, your relationships, your routines. Fewer novel experiences per week means fewer memory landmarks. The year passes with fewer distinguishable moments, and in retrospect it feels compressed.

The Forward/Backward Paradox

Here’s what makes this strange: time in the present feels slow, and time in memory feels fast — and these are inversely related.

A week on vacation feels slower than a week at your desk — every day has novel experiences, you’re noticing more, time seems elastic. But when you look back on a vacation a year later, it feels recent, vivid, present. When you look back on a year of routine, it feels like it vanished.

A week of boredom feels endless. Looking back on a boring year, it seems to have taken no time at all.

The present moment is continuous and dense. Memory is selective and compressed. What feels slow now will feel brief in retrospect, if it generates no landmarks. What feels fast now (the vacation, the new experience) will feel long in retrospect, because the memories are rich.

This is not a quirk. It is fundamental to how memory constructs time.

The Cave Experiment

Michel Siffre was a French geologist who, in 1962 and again in 1972, spent extended periods alone in underground caves — isolated from all time cues. No sunlight, no clocks, no human contact.

When he emerged after 63 days (the 1972 experiment), he believed approximately 25 days had passed. His subjective time had moved at less than half the rate of real time.

Without novelty, without social anchors, without the regular rhythm of external events to create memory landmarks, time collapsed inward. He was alive and conscious the entire period. His subjective experience of it was radically compressed.

This is a more extreme version of what happens in routine. Without novel experience to populate time, the felt duration shrinks.

What This Means Practically

If your sense of time is constructed from memory landmarks, and memory landmarks are created by novel experience, then the rate at which time appears to pass is somewhat within your control.

Seeking new experiences — learning a new skill, visiting an unfamiliar place, taking a class in something you don’t know, having a conversation with someone whose life is very different from yours — fills time with encodable moments. The year will feel, in retrospect, like it contained more.

Routine is efficient. It’s also invisible in memory.

This doesn’t mean you should live chaotically or that comfort is wrong. It means that the way to make time feel full is to ensure that it contains enough distinct, memorable experiences to populate the reconstruction later. The felt duration of a life is not time lived — it’s time remembered.

The Uncomfortable Implication

James noticed in 1890 that years “grow hollow and collapse.” He was describing what happens when novelty runs out — when the days smooth themselves into routine and memory has nothing to anchor to.

The alternative to this isn’t constant novelty for its own sake. It’s intentional experience — putting enough that is new or meaningful into time that the reconstruction doesn’t compress it into nothing.

The summer that lasted forever at nine wasn’t long because you were nine. It was long because every week contained things you’d never done before.

You’re capable of creating that now. It just requires more deliberate effort than it used to.

Time isn’t speeding up. You’re just creating fewer landmarks.

You can change that.