There is a strange, universal feeling that hits most of us in adulthood. Time starts to move faster.

When you were a kid, a single summer vacation felt like an entire geological era. Two months stretched out over the horizon, packed with endless afternoons and vast, empty weeks. Today, two months is just the gap between a couple of project deadlines.

It’s easy to feel a little melancholic about this, as if time is somehow speeding up or slipping away from us. But the calendar hasn’t changed. The clocks are ticking at the exact same speed.

What’s actually changing is the math. We can explain one of the strangest feelings in adult life with just simple fractions.

Our perception of time is not absolute; it is relative. We measure the length of a passing year against the total amount of time we have already experienced.

Think about it like this: When you are 10 years old, a single year represents 10% of your entire existence. That is a massive block of data. It holds a tenth of all your memories, a tenth of all your growth, and a tenth of your entire understanding of the universe. Of course it feels enormous. It is enormous.

But as you age, the denominator of that fraction keeps growing.

By the time you turn 50, a single year is no longer a massive chunk of your timeline. It is now just 2% of your life. It registers as less expansive because it occupies far less relative space in the architecture of your experiences. The unit of time hasn't shrunk, your life has just gotten much bigger.

There is a secondary force at play here, too, the compression of routine.

In childhood, everything is novel. You are constantly learning new rules, navigating new environments, and experiencing "firsts." The brain writes highly detailed, dense memories when processing novel information, which makes that period of time feel incredibly rich and long when you look back on it.

In adulthood, we settle into rhythms. We commute the same route, run the same weekly meetings, and execute the same evening routines. When the brain doesn't encounter novel information, it essentially goes into "power-saving mode" and stops writing high-density memories. Entire weeks can get compressed into a single, blurry file labeled Work.

When you combine the smoothing effect of routine with the shrinking fraction of your age, it perfectly explains the phenomenon. Time is not speeding up, it’s just settling into a much larger container.

This shouldn't be a dark or sad realization. In fact, it is a deeply comforting one. It allows us to appreciate exactly why our early life felt so incredibly vivid and expansive, without feeling like we are losing our grip on the present.

The years aren't actually slipping past you faster. You are just standing on a much taller mountain of experience, which makes everything else look a little bit smaller.

Prompt: A detailed, hand-drawn technical schematic of a cybernetic mechanical stag beetle (lucanidae) rendered as a pencil sketch on a piece of aged, crumpled paper. The beetle is illustrated with visible internal gears, pistons, wires, and clockwork mechanisms. Numerous handwritten labels with leader lines point to specific parts, including 'HYDRAULIC PISTON', 'ARTICULATION JOINT', 'OPTICAL SENSOR', 'MICRO-GEAR', 'ENERGY COIL', 'MANDIBLE LOCK', and 'SPECIMEN: M. STAG_01'. The paper rests on a rustic, dark wooden table. Next to the paper is a prominent, dark coffee cup ring stain. Soft, natural lighting, precise illustration style, shallow depth of field.

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PS—You’re not crazy for feeling like each year passes faster. It’s just math, don’t worry.