Heraclitus and Stoicism

The Pre-Stoic Philosopher who Inspired Marcus Aurelius

Bronze bust of Heraclitus of Ephesus, National Archaeological Museum, Naples, Italy. Image from Wikimedia.

Stoicism began around the year 300 BCE in Athens, a new Hellenistic philosophy established by Zeno of Citium, a Phoenician merchant. But of course Stoicism didn’t come out of nowhere. The most immediate influence was Cynicism, particularly since Zeno’s first teacher in Athens was the famous Crates of Thebes, himself a student of the legendary Diogenes of Sinope. Moreover, the forefather of both Cynicism and Stoicism was Socrates, and in fact the Stoics themselves openly referred to their philosophy as Socratic. Not to mention that Zeno also studied with the Megarian Stilpo, the Dialecticians Diodorus Cronus and Philo, as well as with Xenocrates and Polemo from the Platonic Academy.

Still, there are more ancient influences on Stoicism, and perhaps the most important, as well as the first one of which we have knowledge, is the Presocratic philosopher Heraclitus of Ephesus (535–475 BCE). As it happens, I’ve been reading a wonderful introduction to all the known Presocratics (as well as to the much maligned Sophists), The First Philosophers, by Robin Waterfield (Oxford Classics), which includes a new translation by the author of the known fragments. I highly recommend the book for anyone interested in the beginnings of Western philosophy, but I will focus here on Heraclitus, who had a major impact on the Stoics, and particularly on Marcus Aurelius. (See the excellent annotated edition of the Meditations, also by Waterfield).

The good news about Heraclitus is that he is the first Presocratic of whom we have extended fragments. The bad news is that his style was known to be rather obscure even in antiquity. He did not write books, but aphorisms, probably because the form was more suitable to what was, after all, still largely an oral culture (let’s not forget that Socrates himself refused to write down anything because he distrusted books—thank Zeus for Plato!).

Heraclitus is famous for a number of important themes running through his philosophy, and which influenced not just the Stoics, but several other schools, including a modern approach called process metaphysics.

The first of these themes is that of the Logos, a word that Heraclitus used in a variety of manners. Most comprehensively, it is the rational principle embedded in the functioning of the universe. For Heraclitus, as for the Stoics and many other ancient thinkers, the cosmos was a living organism endowed with reason. That model has, of course, been replaced first by the mechanistic one of Galilean-Newtonian physics, and more recently by the weirdness of quantum mechanics. Even today, though, we have to recognize that the world is, indeed, organized according to rational principles (what is sometimes referred to as “Einstein’s God”), even though we still don’t have much of a clue of where those principles come from. Heraclitus chided his fellow human beings for being capable of understanding the reality of the Logos, and yet sleepwalking through life as if they were incapable of using their own faculty of reason.