By Miguel Oliveira Panão

Humans have a peculiar relationship with time. We all experience it but feel unable to define it. The sequence of events in our life is like traveling with time. But the aging we see in the mirror is like having time traveling through us. How elusive the understanding of time seems to be.

In his book, “The Order of Time,” the physicist Carlo Rovelli says — “Times are legion: a different one for every point in space. There is not one single time; there is a vast multitude of them.” And we understand this because each one of us is unique, has their own time and rhythm. But then Rovelli says something curious:

“Proper times develop relative to each other. (…) The world is not like a platoon advancing at the pace of a single commander. It’s a network of events affecting each other.” 

It means that time is a relational experience. Therefore, it doesn’t make much sense to say — «I don’t have time» — because experiences are not possessions but elements of change. 

Aristotle was the first who recognized time as a measure of change. But why is time such a difficult concept to grasp? It even led St. Augustine to answer the question: “what is time?,” with:  “If no one asks me, I know; if I want to explain it to a questioner, I do not know.” Maybe it’s because we have only one word for “time.” The Greeks had three.

Three were the brothers in the fellowship of time: Chronos, Kairos, and Aion. The last brother Aion expressed the perception of time unbounded, progressing through ages and eternal. Chronos was the sequential perception of time divided into past, present, and future. And Kairos expressed the perception of the right time, an opportune time. However, we often reduce our experience of time to its chronological perception. Always looking at our watches, trapped in their watch hands or digits. Maybe we need to reconnect the several perceptions embedded in the single word we use for “time” with our perception of the world.

The world is changing through the network of events. And let’s agree with Aristotle that time is a measure of change. It means time is not a variable in our fundamental equations but shows how variables change relative to each other. It is curious how physics shows this change through a single equation, containing the difference between past and future

∆S ≥ 0 

This equation corresponds to the change (∆) of entropy (S), the Greek word for transformation. Thus, time is a relational and transformative experience.

Time is not about how things are, but about how they’re always becoming. However, when we think about the world in terms of events instead of things, we focus on the processes allowing us to experience what changes inside us and around us through time. 

Carlo Rovelli says:

“The difference between things and events is that things persist in time; events have a limited duration. A stone is a prototypical “thing”: we can ask ourselves where it will be tomorrow. Conversely, a kiss is an “event.” It makes no sense to ask where the kiss will be tomorrow. The world is made up of networks of kisses, not of stones.” 

I enjoy this analogy because a network of events (and kisses) expresses the relational experience of time and the world in its kairos perception or kairological time.

The reason for the immense value of the experience of time is the realization that we all live in one world. And to keep unity in this world, when some of us walk in daylight while others are getting ready to sleep, we need to synchronize our rhythms. 

A deep relational and transformative experience of time means respecting each other’s rhythms—the rhythms we don’t see but feel. Of course, we always strive for objectivity in science. Still, we should never forget how experiencing the world comes from within us, in the intimate experience of time widening our perspective of being more than a speck in this universe. We are a unique moment in the history of time.

Miguel Panão is a Professor in the Department of Mechanical Engineering at the University of Coimbra and the author of “Learnology – Searching for the Meaning of Lifelong Learning.”