Equilibrium

Equilibrium traces its roots back to the Latin language. The first part of the word is that equi- prefix, and it means exactly what we English speakers today think it means: equal. The second half comes from the root word libra, which can mean either a balance, or to balance.

When these words come together, you can imagine that the scales are balanced. Nothing is particularly out-of-whack.

This funny Latin etymological invention came to prominence during the early stages of the Industrial Revolution, just as different fields in science were starting to revolutionize our understanding of how everything works.

The original idea of balanced scales is still a useful way to think about complex modern systems. We can see this today in physics, chemistry, economics, and even in our social systems. It’s an important concept for us to wrap our heads around!

In physics, equilibrium governs any stable system. This includes giant things like our Sun, which faces its own titanic struggle every moment, as two equally mighty forces struggle against one another, dwarfing any human struggle. Fusion blasts outward from the dense core, pushing against the immense, crushing gravity resulting from the massive size of the Sun. That’s why our own local star doesn’t collapse or expand, but instead stays that same predictable size in the sky each day.

If you add ice cubes to a glass of water at room temperature, the ice will eventually melt, and the temperature inside the glass will be at thermal equilibrium. Even your smartphone in your hand showcases an excellent example of equilibrium, since it’s not falling through your hand or floating in the air: the force of gravity is in equilibrium with the electromagnetic force from your hand.

In chemistry, you can see this in the salinity of our seas. Most oceans and seas are in a sort of loose balance called dynamic equilibrium. This means that the salt percentage in the water stays more or less the same over time, but it’s complicated.

Let’s take the Mediterranean Sea as an example. The Mediterranean is more salty than the Atlantic Ocean, and yet the two bodies of water share a connection in The Strait of Gibraltar, where less salty water flows into the Mediterranean from the Atlantic, and vice versa. The saltier water flows underneath the less salty stuff, not to the left or right of it.

Between this flow of water and the usual evaporation and precipitation dance, the Mediterranean remains very stable and balanced, and it’s a good thing, too! Trillions of animal and plant life forms rely on this sort of equilibrium.

Speaking of animals and plants, they too need to live in a state of equilibrium with their environments. Not all of the people who hunt are saints, but those who follow the rules tend to help to keep preserve the delicate balance of flora and fauna that has been threatened by other humans. By having too many deer grazing on a particular type of plant, that means other animals don’t get to eat those plants, and those other animals can then die as a result.

On the flip side, Americans hunted the bison into near-extinction during most of the 19th century. This rippled through the ecosystem, not only devastating indigenous human populations who relied on the bison for food, but also causing other species to lose valuable, predictable sources of food. Scavengers would pick at bison carcasses, wolves and grizzlies would eat fresh corpses, and even herbivores were affected by the loss of the trailblazing bison, who literally shaped the landscape of the early US.

Your body is a type of ecosystem, too. Just like the environment we live in, our bodies need to find a state of equilibrium, or homeostasis in biological terms. Not only does your body regulate temperature, keeping your blood warm and flowing even when it gets cold around you, but it also regulates a dozen other complex systems.

Your gut biome is a great example of one of these systems. The bacteria cells living in your stomach and intestines vastly outnumber your human cells, so it’s incredibly important to have the right type and amount of them living inside you at any given moment. What you eat and the medications you take can have a huge impact on how you keep this scale balanced.

You’ve got other biological systems in your body that continually wrestle to stay balanced, but there’s another type of equilibrium that’s equally important: your mental and emotional state. Your own life needs to be in balance, not just your physiological state.

If you’re not motivated to do this for personal reasons, keep in mind the mantra that you need to put your own oxygen mask on first before helping others. This means that you’ll be emotionally and mentally able to help other people, but this can only happen once you take the time to understand your own emotional state.

Every so often, put your own mental finger to the wind, so to speak. Which way is your mind’s breeze blowing? If you’re bothered by something, why is that, and is there something you can do to address it? If you don’t stop to calibrate yourself, you can find that you can run out-of-whack for quite a long stretch of time.

There are other types of equilibrium I didn’t get to touch on, like the kind you see in financial markets (very dynamic!) as investors wrestle over the price of a stock, or how the average price of a taco can stabilize in a particular city for a few years. Social equilibrium is another form worth visiting in the future; it more or less describes whether and how we all get along with one another.

Both of these categories share common traits with the examples from biological, ecological, physics, and chemistry systems that are constantly seeking to stay in balance. In all cases, there are multiple inputs and outputs that need to be considered, and when one changes, the others all need to adjust too.

Consider your own mental and physical state right now. Are you currently in a state of equilibrium, or are some forces out-of-whack? Are there any adjustments you want to make?