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History of Science Ancient Egypt

History of Science Online

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LibraryThing: Science in Ancient Mesopotamia Week 3: Ancient Egyptian and Aegean science

Herakleitos of Ephesos (fl. 475 B.C.)

| Presocratics Index | Intro | Thales | Anaximandros | Anaximenes | Herakleitos | Parmenides | Zenon | Melissos |
| Atomists: Leukippos and Demokritos | Anaxagoras | Empedokles | Significance of the Presocratics |

Theater of Ephesos at livius.org Another early natural philosopher whom Aristotle numbered among the physicists was Herakleitos of Ephesos (read about Ephesos at Wikipedia or Livius.org; cf. Theater of Ephesos, right, from livius.org).

Herakleitos was melancholy and aloof, frequently critical of others. For example, he once described his compatriots as follows:

"The Ephesians would do well to hang themselves, every grown man of them, and leave the city to beardless lads; for they have cast out Hermodoros, the best man among them, saying, 'We will have none who is best among us; if there be any such, let him be so elsewhere and among others.'"

Sayings such as "Asses prefer straw to gold" have been taken to support the characterization that he was contemptuous of common people. But he could also be critical of learned elites, as in this assessment of medical practitioners: "Physicians who cut, burn, stab and rack the sick, demand a fee for it which they do not deserve to get."

Like the Milesian monists, Herakleitos took up the problem of explaining matter and changes in matter.

1. The Problem of Change

Herakleitos changed the emphasis from matter (as with the Milesians) to changes in matter, the reality of change: all things are changing. This is the import of his phrase:

“You cannot step twice into the same river, for fresh waters are ever flowing around you.”

Artemis at Ephesos, livius.orgThe question is not of matter only, but also of the changes through which matter persists. Matter cycles. The question “What is the underlying nature or matter?” is not sufficient by itself to explain the nature of things. A pond and a river are both made of water, but the latter one consists of moving water. Thus Herakleitos emphasized that “All things are in a state of flux,” a tension of opposites. Despite the fact that appearances may remain much the same, "Nature loves to hide." Matter perpetually changes beneath the appearances.

Consistent with this emphasis on change, Heraclitus rejected the three earlier candidates for the one ultimate substance (water, apeiron, air), and nominated fire instead. Fire exemplifies wonderfully that which is always changing, yet remains much the same. Fire includes both a flame (which displays fire to the sense of vision) and heat (which manifests fire to the sense of touch). Fire is the principle of all things. A flickering flame is always changing but its appearance never changes; thus, it is a model of the nature of the universe. Fire, or heat, is also essential for life. "The world is an eternal fire which transforms itself." Fire transforms a multitude of things, kindling and consuming here, ebbing and going out there. Fire exemplifies a tension in balance, the hidden attunement of the universe. "God is day and night, winter and summer, war and peace, surfeit and hunger; but takes various shapes, just as fire, when it is mingled with spices, is named according to the savour of each." Therefore the All is one, and the one is Fire.

2. Logos as the principle of ordered change

If all things like fire are ever-changing, why are changes often imperceptible? Or, to put the problem another way, why are changes not haphazard? Instead, changes seem to hide profound order and harmony. For Herakleitos, changes are orderly because they are governed by a universal principle or Logos. The Logos produces an outcome of harmony and order through change.

"Of the Logos, which is as I describe it, men always prove to be uncomprehending, both before they have heard it and once they have heard it. For although all things happen according to this Logos, men are like people of no experience, even when they experience such words and deeds as I explain, when I distinguish each thing according to its constitution and declare how it is; but the rest of men fail to notice what they do after they wake up, just as they forget what they do when asleep. Therefore it is necessary to follow the common; but although the Logos is common, the many live as though they had a private understanding. Listening not to me but to the Logos it is wise to agree that all things are one."

Logos (the root of "logic") could be translated as reason, ratio, word or languge, theory, or definition; I prefer to leave it untranslated. Herakleitos sometimes referred to Zeus or to god as the Logos. For him, a human being is one moment in the ongoing Logos. The Logos is manifest in reason, the fiery element in humanity and the cosmos. In this respect, as we shall see, Herakleitos' views were later taken up by Stoic philosophers in the Roman era. In the Roman era, the Logos of various sources, including Herakleitos, would become transformed into the idea of "natural law."

First principle
Thales of Miletos
Anaximandros of Miletos
Anaximenes of Miletos
Herakleitos of Ephesos


"Men are as unable to understand it when they hear it for the first time, as before they have heard it at all." Herakleitos of Ephesos

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HSCI 3013. History of Science to 17th centuryCreative Commons license
Kerry Magruder, Instructor, 2004
Brent Purkaple, TA

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Many thanks to the pedagogical model developed in Mythology and Folklore and other online courses by Laura Gibbs, which have been an inspiration for this course.

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