Eon (or) Flux?

The oldest dispute in Western philosophy, one that continues to influence the way scientists and philosophers think today, can be summarized as the battle between “Being” and “Becoming.”

Here, “Being” means something permanent, unchangeable, while “Becoming” means the opposite, something that changes and transforms. More than twenty-five centuries after Thales of Miletus considered the question, siding with Becoming as his choice, we remain as stuck as ever.

Those who dismiss this issue as another irrelevant philosophical debate, and plow ahead doing his or her thing, are missing the point. And, very possibly, an opportunity to break free from this tug-of-war and see the world anew.

Let me illustrate where this is coming from. Thales believed Nature was an organism, pulsating with life and transformation. He considered water to be the fundamental substance of the world, the essence of all there is. Why water? Because water morphs into different states—gas, liquid, solid—and is essential to life.

Thales used water as a metaphor for the transformations he witnessed around him. He saw Nature as being in a constant state of flux. To him and his Ionian followers, the essence of the world was transformation. Soon after, Parmenides of Elea (born circa 515 BCE) responded with the opposite view. No, he said, what is essential cannot change, for if it does it becomes something else. And how could the essence of everything be a fluid thing? To Parmenides, the essence of everything was Eon (“What Is”), the unchangeable.

This tension among the Pre-Socratics was taken up by Plato, who sided mostly with Parmenides. Distrust the world of the senses, said Plato, and seek the truth in the realm of thought. The only perfect circle is the idea of the circle, the one you imagine in your head. Any concrete representation of a circle would be imperfect. Mathematics, in its logical structure, came to represent this perfection. Beauty, seen as a mathematical expression of the deepest layers of reality, came to be identified with truth.

Centuries passed, and the development of modern science, with its insistence on observation and experimentation, forced natural philosophers to confront physical reality in the face, beautiful or not. This is where we connect the ancient Greek debate to what we are doing today, equating science with the pursuit of truth. But what truth is this?

Thales? Parmenides? Or both?

Poking around, we find echoes of both Thales and Parmenides. As physics developed, one of its central goals became the search for the “laws of Nature.” Many natural phenomena exhibit patterns of behavior that are quite stable, in that we can model them with mathematical equations that obey certain rules. (See my blog post, “There Is No Perfect Map.”) Such rules, if applied to a sufficiently large set of phenomena, become what we call laws of Nature.

For example, energy conservation. As far as we can tell, all physical processes conserve energy, in the sense that the same amount of total energy can be accounted for before and after the process happened. If the system is “dissipative,” that is, if it loses energy as time goes by, we can search around to see where it goes. Electric currents, for one, dissipate energy through the collisions of electrons as they flow along metal wires. Energy goes away in the form of heat, but the total, if we add up the heat, is the same.

The beauty of such laws is that they hold everywhere in the Universe, across space and time. They represent, in a very real sense, the Being of the cosmos, the modern incarnation of Parmenides’ unchangeable Eon. Although there have been proposals that challenge this immutability, most notably from Harvard philosopher Mangabeira Unger and Perimeter Institute physicist Lee Smolin, the essential assumption of a law of Nature is its immutability since the beginning of time. Of course, we know very little about the physics of the very early Universe, and it is possible that laws were not as steady then. But as far as we can tell today, no measurement found any such violations yet.

Balancing this search for the immutable in the cosmos is today’s overwhelming view of physical reality is one of constant change. Anywhere we look—from the fleeting existence of elementary particles of matter that materialize and disappear from the quantum vacuum in fractions a second, to the limited life span of all creatures, from the birth and death of stars to the history of the expanding Universe—we see Nature in a constant state of flux. If there is one word that could characterize the physical reality we see around us, that word would be transformation.

Whence truth?

We can see now why the age-old controversy of Being versus Becoming is still alive. From the point of view of the laws of Nature, we see immutability. But from the point of view of matter, we see change and transformation.

Where should one go to find truth, then?

My answer is to both. We can think of the laws of Nature as the choreographer responsible for the dance of matter and energy. The show—physical reality—needs both.

The alternative is an unruly cosmos, one that would surely be devoid of any organized structure, including us. A choreography with no dancers is as meaningless as dancers without a choreography. A material universe with no laws is as meaningless as laws without a material universe.

The false dichotomy is as meaningless as the mind-body problem: what is a mind without a body or a body without a mind?

It’s time for Thales and Parmenides—and the countless disputes that followed and still rage on—to lay down their swords and embrace the simple fact that they need each other to make sense of the world.

Templeton Prize winner Marcelo Gleiser is a professor of natural philosophy, physics and astronomy at Dartmouth College.