The question
Why does a holiday fly by but seem long afterwards, and why do years speed up as we age?
The short answer
We judge time two ways: while it passes and looking back. New, varied experiences leave more memories, so they feel longer in hindsight even when they felt quick at the time.
What science knows
Established SciencePsychologists distinguish prospective timing (judging time as it passes) from retrospective timing (judging it from memory). A busy, novel day can feel fast while living it and long when remembered, which the writer Claudia Hammond called the “holiday paradox”.
Unexpected events tend to seem longer than routine ones, an effect researchers call the oddball effect.
The pattern
Established MathematicsOne old idea, proposed by Paul Janet in 1877, is proportional: at age 5 a year is a fifth of your life, at 50 a fiftieth. Whatever its merits as psychology, the arithmetic is striking.
What is still uncertain
Mixed EvidenceSurveys find that people of all ages feel weeks and months pass at similar speeds; the sense of speeding up is stronger for years and decades. In a 2007 experiment, people in free fall remembered the fall as longer, but did not perceive time in finer detail during it, which suggests memory, not perception, stretches.
Why humans find it interesting
Cultural TraditionMany languages distinguish clock time from lived time; the Greeks had chronos for measured time and kairos for the right moment.
CUE perspective
CUE PerspectiveCUE’s focus on timing is closer to kairos than chronos: not how long something takes, but whether it is the right moment.
The science suggests one practical idea: variety and attention make time feel fuller, whatever your numbers say.