"Time flies so fast..." How many people will exclaim like this about the just-ended 2023?

The passage of time, many people believe, have this feeling, when we were young, a day was very long, after school, we could still play with friends for a long time before going to bed;

but now day is simply too fast, having dinner after work isn't early anymore, and lying down to browse on the phone quickly leads to midnight.

Even though a day has always been 24 hours, why do we increasingly keenly feel the "fleeting time" as we age?

Age Proportion Theory

Neurobiologists point out that childhood time passes leisurely, while time flies by quickly in adulthood, which is a very common experience for people.

The reason for this change doesn't have much to do with the actual speed of time passing, but rather with our ability to perceive time.

But why is it that time seems to fly faster as we get older, rather than the other way around?

To explain this issue, philosopher Paul Janet proposed the Age Proportion Theory, which suggests that our perception of time is relative, and age plays a significant role. As age increases, the percentage of time units in our lives decreases, making that period relatively faster.

How do we understand this theory?

As age increases, each unit of time occupies a smaller proportion of your life experience.

This theory was first proposed by Paul Janet in 1877. He believed that a person would compare the time they experienced with their life experiences. For a ten-year-old child, one year is 1/10 of their life; for a 50-year-old person, one year is 1/50 of their past.

From birth to the first month, a week is a quarter of your life, which seems very long for you as a newborn.

At 14, one year is 7% of your life experience, which also seems like a long time.

But by the time you reach 30, a week's proportion in your life is minuscule.

At 50, a year is only 2% of your life, so subjectively, you will perceive these seemingly insignificant periods passing quickly.

Fewer Novel Experiences

Many of us have experienced that the first time we do something, it feels longer than subsequent times. On the first day at a new school or job, or even on the first day of a holiday, time seems to pass slowly.

There's also the phenomenon of individuals feeling like time slows down during life-threatening situations, where even fractions of a second can seem exaggeratedly long due to heightened subjective awareness.

The prolongation of time due to novelty is a well-documented phenomenon that can be studied in laboratories. Participants are asked to estimate the duration of a series of stimuli, and the results show that new stimuli are perceived as lasting longer than repeated or less noticeable stimuli. The brain gives more subjective time to new stimuli because they require more cognitive processing.

When we're young, everything is novel. Many things are experienced for the first time. Even if it's not a completely new experience, you're still exploring new ways of dealing with it.

So, some argue that time seems to accelerate as we grow older because we encounter fewer new things—the world of middle-aged people is predictable, and our brain's response accelerates our engagement with this world. The early years of life are expanded and prolonged by new challenges, while the middle years are compressed due to a lack of new experiences.

Besides these mainstream viewpoints, there are several other explanations for why time seems to pass more quickly, but most are related to factors such as memory, age, neural transmission, subjective emotions, etc.

Since the feeling of time passing more quickly is essentially a psychological illusion, we can make our brains more active by continuously experiencing new things through learning new skills, extensive reading, making new friends, etc.

These methods not only enhance your sensitivity to the passage of time but also make your life more colorful.