Heraclitus was an ancient greek philosopher born in Ephesus (near Miletus, the “birthplace of philosophy”) in 540 BC. Heraclitus famously wrote in a way that is very hard to read, and for that reason the other philosopher’s called him “The Obscure” and “The Riddler.” He believed there was a fundamental unity of experience which the other philosophers had not recognized. He called this the Word or logos which he believed operated in the world through the constant changing of opposites into one another. He considered fire the most important element, symbolizing this eternal change.

Heraclitus is the first Greek philosopher to come from an aristocratic family. He became disillusioned with his fellow citizens when they chose to remove a prominent figure from office. He didn’t think that most people knew what they were doing, and were quick to accept tradition or go along with the opinions of others. For this reason, he was in favor of an aristocratic government (aristos) rather than a democracy exclaiming “One person is ten thousand to me if he is best.” His disillusionment with others, who could not understand his philosophy, led him ultimately to live a life of solitude in the mountains and to be known also as “The Weeping Philosopher.”

Heraclitus saw that the world is in a constant state of flux. He believed everything changes into it’s opposite, and that this is what maintains the world. “Cold things warm up, the hot cools off, wet becomes dry, dry becomes wet.” The philosophers before him thought there was a fundamental principle of reality (arche) and they identified it with a substance (water, air, the apeiron). For Heraclitus, the fundamental principle of the world isn’t a substance, but rather the principle that everything changes according to a divine guidance, which he called the Word (logos).

By discovering the logos of the world, Heraclitus believed he understood the way the world worked. He saw that the elements of the world are constantly changing into their opposites. “Fire lives the death of air, and air lives the death of fire; water lives the death of earth, earth that of water.” The strife and conflict which we experience actually creates a fundamental harmony in the world. Just like the tension of a bow requires the wood and the string, so the world requires day and night, summer and winter, life and death. For this reason, he considered war and peace to be equally necessary.

Heraclitus saw all things as one. There are many things (plurality) and there is but one thing (unity), and this is not a contradiction but two different and equally true aspects of reality. To illustrate, he discusses a river. A river is the result of the rushing of new waters. But only through the new waters is it a river in the first place (instead of a lake or pond). As he famously said, “It is not possible to step twice into the same river.” Through changes on one level, it allows for stability on another.

Heraclitus’ saw the world as eternal, an “ever living fire.” He is the first to refer to the world as a cosmos (“world order”). Fire is primary for Heraclitus because it is the element that is most changing, and as such he used it as a symbol of the constant change that maintains the cosmos. He also identifies fire with the soul and the logos. In this way, he understands that which occurs within ourselves, in the physical world, and in fundamental reality as being of the same fiery nature.

Heraclitus’ understanding of the soul, God and reality is a major break with the traditional Greek understanding of the world. For Heraclitus, the world is no longer inhabited by the Olympic Gods. Instead, the world governed by the divine logos. Zeus’s lightning bolt is no longer hurled by an anthropomorphic (“human like”) being, but rather serves as a symbol of the direction of the universe. Perhaps most important, Heraclitus believes the soul is immortal and what happens to the soul depends on how fiery it is when one dies. In this way, he gives people a way of doing things in this life to improve their chances of having a better afterlife other than prayer and giving gifts to the Gods. Instead, one must seek understanding of the logos and to act in accordance with it.

Unlike the Milesian philosophers who were mainly interested in the way the physical world works (“natural philosophy”), Heraclitus believed the logos applied both to the cosmos as well as to the way people organize themselves (i.e. politics). He saw human laws as being nourished by the divine law, and believed that “people should fight for their laws as they would for their city wall.” He sought to replace the Homeric virtues of beauty, wealth and physical prowess with the attainment of understanding the logos as the prime aim of life. His understanding of the physical world would go on to influence the Stoics and his understanding of aristocracy as the best form of government as well as his use of the written word to teach philosophy would leave it’s mark on Plato.