Heraclitus' Theory of the Psyche

Christopher D. Green
Department of Psychology
York University


Heraclitus was the most important philosopher between Pythagoras and Parmenides. He lived in the city of Ephesus, of which substantial ruins remain still on the western coast of present-day Turkey. The region was then called Ionia. His exact dates are not known. McKirahan (1994) reports them as being 540-480 BC.

Unlike Xenophanes and Pythagoras, he did not flee the Persian invasion of Ionia (546 BC) for Italy; he survived it, and even flourished under it. As with all other early pre-Socratics, none of Heraclitus' original writings remain, although he was said to have written, as was traditional for philosophers of his time, a treatise generally on nature (physis). What is known of Heraclitus' philosophy is contained in more than 100 fragmentary mentionings of him by his successors. Many of these fragments are obscure, enigmatic, and even bizarre. Diogenes Laertius, a biographer who lived about 300 AD, recounted a story (repeated by Barnes, 1987, pp. 57-58) that Socrates, upon reading a copy of Heraclitus' work (allegedly given to him by the great tragic playwright, Euripides), said "What I understood was good.... But it would take a Delian diver to get to the bottom of it."

Heraclitus frequently asserted the unity of opposites: "the road up and down is one and the same road" (DK22 B60); "while changing, it rests" (DK22 B84a); "in the case of a circle, beginning and end are the same" (DK22 B103); "cold things become warm, a warm thing becomes cold..." (DK22B 126); and perhaps strangest of all, "immortals are mortals, mortals immortals: living their death, dying their life" (DK22 B62).

Others of his comments are savagely critical of his conetmporaries and immediate predecessors: "Pythagoras is the chief captain of swindlers" (DK22 B81a ); Pythagoras...practiced inquiry beyond all other men...artful knavery" (DK22 B129). Still others are astoundingly astute: "Poor witnesses for people are eyes and ears if they [the people] have psyches that do not understand their [the senses'] language." (DK22 B107).

This was only one of many mentions of psyche in his sayings. Whether they can be assembled into a coherent psychology is a question to be pursued below, but only after first briefly looking at what seems to have been his more general world view.

Herlaclitus may have been one of the first victims of a major misquotation in philosophical history. No less an authority than Plato (Cratylus, 402a) said he had argued that "it is not possible to step twice into the same river," and this claim continues to be widely attributed to Heraclitus to this day. This misunderstanding may have been due to a group of proto-skeptics acitve in Ephesus at Plato's time (about a century after Heraclitus' death) who erroneously called themselves "Heracliteans." Arius Dydimus, a 1st century BC doxographer reported that what Haeraclitus had, in fact, said was, "as they step into the same rivers, different and still different waters flow..." (DK22 B12, emphasis added), a very different sentiment indeed: the river remains the same but its material composition changes as different water flows through it.

This calls into question the accuracy of another widespread belief about Heraclitus' philosophy--viz., that he claimed everything to be continually in flux (e.g., Plato, Cratylus, 401d). As T. M. Robinson (1987) has suggested, it seems that in using the example of rivers, Heraclitus was "stressing their unity amidst change, rather than simply their change" (p. 84). That is, what Heraclitus may have been trying to get at is that the material out of which a thing, such as a river, is comprised does not alone define its existence. There is a constant underlying structure or organization that determines the thing's identity. This idea of an underlying structure governing the organization of the cosmos bears a remarkable resemblance to the meaning of a term that would later become, perhaps, the most important in Greek philosophy: logos. Logos--a noun dervied from the verb, legein, "to speak"--originally meant "something spoken," but later broadened in meaning to encompass an account or explanation of how a thing had come to be. More broadly still, it might be equated roughly with a natural law or underlying truth. It is often translated as "word" (as in the first sentence of the Book of John in the New Testament--"In the beginning was the Word [logos]") but this rendering can be very misleading if taken too literally. Logos is also the root of our suffix, "-logy," meaning "study of," as in "psychology," "geology," "theology," etc.

McKirahan (1994) has called Heraclitus' invocation of logos his "greatest discovery" (p. 133). T. M. Robinson (1987, pp. 4-5), however, has warned that later Stoic philosophers, themselves highly enamored of the logos, may have exaggerated its importance in Heraclitus' thought. Many classicists now hold that in Heraclitus' time, logos still meant simply "something said" or "an account" of something. If so, when he began his treatise with the passage, "all things come into being in accordance with this logos" (DK22 B1), he may have simply meant to say that his account of the world was true, not that he had discovered a cosmic organizing principle called logos. Several of the quotations that are discussed below with respect to the psyche seem to conflict with this conservative interpretation, however.

In either case, so far was he from holding the view that the world is in the throes of a continual wild, random flux, that he is reported to have once said, "listening not to me, but to the logos, it is wise to agree that all things are one" (DK22 B50). He also believed that the truth about the world is available to all who care to apprehend it, a belief that was likely at the source of his sharp criticism of the Pythagoreans who, in their enforced secrecy, acted "as though they had a private understanding of the cosmos" (DK22 B2).

With all this in mind, we can begin to make more sense of Heraclitus' seemingly paradoxical claim that, "we step and do not step into the same rivers" (DK22 B49a). There is a sense in which we never step into the same river, because the water of the river is undergoing continual replacement. There is another sense, however, in which the river remains the same despite this ongoing change in its material base. Extending the puzzle to human existence itself, Heraclitus continued, "we are and we are not."

Over 2000 years later, the British philosopher John Locke would discover the problem anew when he wondered if a ship remains the same ship if it continually has small repairs done to it over a period of many years, each replacing an original piece here or there with a new one, until finally it contains none of the material that went into the building of the ship initially. Again, in contemporary times, psychological researchers who believe that the mind is simply a computer program that runs on the "hardware" we call the brain (e.g., Putnam, 1960/1975), have stumbled upon the same problem. They argue that the mind is not so much a function of the particular brain in which it is grounded but, rather, of the organization of the information that the brain stores and processes. Because any brain--or in fact anything complex enough to be a computer--could store and process the same information, they claim that one and the same mind could be transported from brain to brain, or even from brain to computer. Marvin Minsky has even gone so far as to suggest we could make ourselves immortal by simply moving our minds to computers before our bodies die.

This is by no means to claim that Heraclitus was some sort of proto-computationalist about the mind. That would be the worst sort of anachronism. It is only meant to show that some of the problems addressed by Heraclitus are still with us today.

To understand Heraclitus' view of the psyche, it is perhaps best to begin by simply presenting what he is held to have said with respect to it.

What are we to make of this collection? In several places he mentions that wetness is bad for psyches; that it can even destroy them. This would imply that, if psyches were thought to be made of one of the basic elements, they are likely made of fire. As fire is extinguished by water, so can the psyche. This has become the standard interpretation of Heraclitus' position on the matter (see, e.g., Barnes, 1982, pp. 472-474; Schofield, 1991, pp. 20, 29-30; McKirahan, 1994, pp. 140, 146). Indeed, fire was the most important part of the Heraclitean cosmology; he thought it, rather than Thales' water or Anaximenes' air, to be the primary stuff of the cosmos (DK22 B90; see also Barnes, 1982, pp. 60-62). This would represent quite a break with tradition dating back to at least Homer (300 years earlier) holding that the psyche is airy and vaporous. There is some dispute about this, however. Kahn (1979), for instance, argues that the Heraclitean psyche actually falls within the airy tradition. One is reminded here of Anaximenes' belief that water is just compressed air. Perhaps it is the compression of a psyche to death that converts it into water.

Whatever else, psyche for Heraclitus, contrary to Pythagorean claims, seems to have been regarded as being part of the physical chain of being. It is important, however, to recognize that physis, or nature, was not thought to be purely material by the Greeks of this time. This is a point that the notable Aristotelian scholar, Jonathan Barnes (1982), seems to forget when he describes not only Heraclitus' account of the psyche, but those of all the pre-Socratics up to his time, as having been "uncompromisingly materialistic" (p. 475). Marcovich (1967), too, has argued that Heraclitus believed the psyche to be a fully physiological entity, in the modern sense. But more conceptual subtlety than this is required.

The conceptual schemes of the Greeks differed significantly from ours. As Cornford (1912/1991), and more recently McKirahan (1994, p. 31) have noted, the universe was thought of by the Ancient Greeks as being a living substance, a belief evinced every moment of every day by the cosmos' constant motion. Thus, although it is certainly possible, as Barnes insists, to hold the theories of the pre-Socratics against our category of matter for comparison, it is not clear what is to be gained by such an exercise. The elements as understood by the Greeks fit with our contemporary concept of matter only very approximately, Barnes' claim to the contrary notwithstanding. It is of more interest to attempt to reconstruct the conceptual schemes under which the pre-Socratics operated, with the aim of finding out just what they thought they knew; what they considered to be knowledge of the psyche.

Another psychological issue to be grappled with is whether Heraclitus believed the psyche to be mortal or not. A few passages suggest to some classicists (e.g., Kahn, 1979, p. 249) that Heraclitus believed at least some psyches to be immortal; viz., those of noble people. Other classicists (e.g., Nussbaum, 1972, p. 169) reject this claim, arguing that Heraclitus believed that the psyche dies at the point of bodily death. McKirahan (1994, p. 146) argues that the fate of the psyche depends on how "fiery" it remains at the point of bodily death. Souls made "wet" by drunkenness or disease may die. Those that remain "dry," as those of the warrior were said to, survive.

In uncharacteristic harmony with the Pythagorean doctrine, it seems that Heraclitus also believed the psyche to be the source not only of life, but also of reason and rational control; that which interprets (or fails to) the "language" of the senses (DK22 B85), and that which is lost in the face of desire (DK22 B107). Physicalism, then as now, has trouble accounting for the rational aspect of mind. Unfortunately, precise interpretative alternatives to the physicalist thesis are hard to come by. Schofield (1991), for instance, offers only the commonplace that Heraclitus presented no determinate theory of the psyche at all.

In light of this, perhaps the most telling of Heraclitus' comments on the psyche is that it has a logos, that is constantly expanding; one so "deep" that no one will ever discover it fully. Certainly we have not as yet.


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