As a single, unified thing there exists in us both life and death, waking and sleeping, youth and old age, because the former things having changed are now the latter, and when those latter things change, they become the former.
Fragment 88, quoted in pseudo-Plutarch, Consolation to Apollo
Change alone is unchanging.
Herakleitos and Diogenes, part 1, fragment 23
Cutting and burning, which are normally bad, call for a fee when done by a surgeon.
Even sleepers are workers and collaborators on what goes on in the universe.
The Cosmic Fragments, number 90 (c.480BC)
Everything rests by changing.
Eyes and ears are bad witnesses to men if they have souls that do not understand their language.
Fragment 107, quoted by Sextus
God is day and night, winter and summer, war and peace, surfeit and hunger; he changes the way fire does when mixed with spices and is named according to each spice.
Fragment 67, quoted in Hippolytus, Refutations
Hide our ignorance as we will, an evening of wine soon reveals it.
Herakleitos and Diogenes, part 1, Fragment 53
History is a child building a sand-castle by the sea, and that child is the whole majesty of man’s power in the world.
Herakleitos and Diogenes, part 1, Fragment 24
If one does not expect the unexpected one will not find it out, since it is not to be searched out and is difficult to compass.
Immortal mortals, mortal immortals, one living the others’ death and dying the others’ life.
The Cosmic Fragments, number 67 (c.480BC)
It is necessary to understand that war is common, strife is customary, and all things happen because of strife and necessity.
Fragment 80, quoted in Origen, Against Celsus
Listening to the Logos rather than to me, it is wise to agree that all things are in reality one thing and one thing only.
Fragment 50, quoted in Hippolytus, Refutations IX
Men who wish to know about the world must learn about it in its particular details.
Herakleitos and Diogenes, part 1, fragment 3
Nature loves to hide.
Fragment 208, quoted by Themistius
Night and day, which Hesiod had made parent and child, are, and must always have been, essentially connected and interdependent.
Nothing is, everything is becoming.
On those who step in the same river, different and different waters flow…
Fragment 12, quoted in Arius Didymus
Out of all things there comes a unity, and out of a unity all things
Fragment 10, quoted in Aristotle, On the World
People that love wisdom must be acquainted with very many things indeed.
Sea is the most pure and the most polluted water; for fishes it is drinkable and salutary, but for men it is undrinkable and deleterious.
Fragment 61, quoted in Hippolytus, Refutations
The hot substance and the cold form what we might call a hot-cold continuum, a single entity.
The path up and down is one and the same.
Fragment 60, quoted in Hippolytus, Refutations
The things of which there is seeing and hearing and perception, these do I prefer.
Fragment 55, quoted in Hippolytus, Refutations
The unapparent connection is more powerful than the apparent one.
Fragment 54, quoted in Hippolytus, Refutations
The world, an entity out of everything, was created by neither gods nor men, but was, is and will be eternally living fire, regularly becoming ignited and regularly becoming extinguished.
The Cosmic Fragments, number 20 (c.480BC)
There would be not right without wrong.
They do not understand that what differs agrees with itself: there is a palintonos (counter-stretched) harmony, as in the bow and the lyre.
Fragment 51, quoted in Hippolytus, Refutations
They vainly purify themselves of blood-guilt by defiling themselves with blood, as though one who had stepped into mud were to wash with mud: he would seem mad if anyone noticed him doing this. Further, they pray to these statues, as if one were to carry on conversations with houses, not recognizing the true nature of gods or demi-gods.
Fragment 5, quoted in Aristocritus Theosophia
Those who speak with sense must rely on what is common to all, just as a city must rely on its law, and with much greater reliance. All the laws of men are nourished by one law, the divine law; for it has as much power as it wishes and is sufficient for all and is still left over.
Fragment 114, quoted in Stobaeus, Anthology
To do the same thing over and over again is not only boredom: it is to be controlled by rather than to control what you do.
Herakleitos and Diogenes, part 1, fragment 89
To God all things are beautiful and good and just, but men have supposed some things to be unjust, others just.
Wisdom is one thing: to understand with true judgment how all things are steered through all.
Fragment 41, quoted in Diogenes Laertius, Book IX
You can never step twice into the same river; for other waters are ever flowing on to you.
Quoted in Hippocrates, On The Universe, aph. 41
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