Against the Milesian Inquiry into Nature and its Ontology

Map of the Ancient World Elea was a Greek city in what is now southern Italy.

Xenophanes was born in Colophon (a Greek city in Ionia) in about 570 BCE and lived to "a very great age" (Diogenes Laertius, Lives the Eminent Philosophers IX.2).

"[Parmenides] was instructed by Xenophanes" (Diogenes Laertius, Lives the Eminent Philosophers IX.3).

Parmenides is one of the first philosophers in the new philosophical tradition that began with Thales. He was active in the early to the middle part of the 5th century BCE.

Plato (429-347 BCE), in his dialogue Parmenides, indicates that the historical Parmenides visited Athens when Socrates was was a young man and Parmenides himself was about sixty-five. The city of Athens executed Socrates in 399 BCE when he was seventy. If Socrates was twenty when Parmenides visited Athens, then Parmenides was born in about 515 BCE.

The connection between Parmenides and the Milesians is uncertain, but it may have run through Xenophanes. Xenophanes came from Colophon, near Miletus, and he seems to have moved to southern Italy. Parmenides himself does not mention any of his predecessors by name.

Nothing comes into Existence

What survives from Parmenides are fragments of a poem written in the traditional epic medium of hexameter verse. Parmenides does not identify those he argues against in his poem, but given his argument, it is natural to understand him as arguing against Thales and the inquirers into nature.

Parmenides seems to think that the inquirers into nature are confused about what exists. As he seems to understand them, they think that the objects salient in experience exist in terms of changes in the nature of things. Parmenides argues that this conception is incoherent. He argues that "reason" shows that coming into and going out of existence are impossible.

"Come now, and I will tell, and you, hearing, preserve the story the only routes of inquiry there are for thinking; the one, that it is and that it is not possible that it not be, is the way of persuasion (πειθοῦς) (for it attends upon truth), the other, that it is not, and that it is right not to be, this I point out to you is a way altogether indiscernible: for you could not know what is not (for it is not to be accomplished) nor could you point it out..." (DK 28 B 2).

"For the same thing is for thinking and for being (τὸ γὰρ αὐτὸ νοεῖν ἐστίν τε καὶ εἶναι)" (DK 28 B 3).

"[The path] on which mortals, knowing nothing, wander, two headed; for helplessness in their breast directs their wandering thought; they are carried along deaf and blind alike, amazed, uncritical hordes for whom to be and not to be are supposed to be the same and not the same, and the path of all is backward-turning" (DK 28 B 6).

"It has been named all the names which mortals have laid down, believing them to be true, coming-into-being and perishing, being and not being, changing place and altering bright color" (DK 28 B 8).
"For what birth could you seek for it? How, from what could it have grown? Not from what is not—... for it cannot be said nor thought that [it] is not; and what need could have impelled it to grow later rather than sooner, if it had had nothing for its beginning? So it is necessary that it either be completely or not at all. And neither will any force of belief ever affirm that out of what is not something is born.... [J]ustice has not, loosening its fetters, allowed it either to be born or to be destroyed, but holds it fast. The judgment on these matters depends upon this: [it] is or [it] is not? Well, it has been decided, as is necessary, to abandon the one as unthinkable, unnameable (for it is not the true road), and thereby that the other, by consequence, exists and is real. ... And how could it be born? For if it was born, it is not, not any more than if it is going to be someday. In this way birth is extinguished and destruction unknowable" (Parmenides, DK 28 B 8).

An Analysis of the Reasoning

It is not easy to see just what Parmenides is thinking, but his arguments for the conclusions that "birth [coming into existence] is extinguished and destruction [going out of existence] unknowable" seems to proceed by (what became known in Latin as) reductio ad absurdum:

reductio, "a leading" ad, "to" absurdum, "absurdity"

----------------- ¬Introduction, 1
   ¬ Assumption

Assume that some object o comes into existence. It follows that "is not" is true of
o before it comes into existence. This, however, is absurd: "is not" cannot be true
of anything. Hence, contrary to the assumption, nothing comes into existence.

Assume that some object o goes out of existence. It follows that "is not" is true of
o after it goes out of existence. This, however, is absurd: "is not" cannot be true
of anything. Hence, contrary to the assumption, nothing goes out of existence.

In each case, the conclusion follows if the consequence deduced from the assumption is absurd. The problem, is that it is not clear that this consequence is absurd. Parmenides tries to explain why "is not" cannot be true of anything, but his explanation is too obscure to be persuasive.

Knowledge, Reason, Experience

In addition to his argument for his conclusion, Parmenides has an explanation for why human beings believe that things come into and go out of existence even though "reason" shows this to be impossible. He thinks that although human beings can form beliefs in terms of reason, "experience" is the much more common way for them to think about things. Reason reveals how reality is, but the habit of relying on experience for beliefs is ingrained in human beings.

"In these verses Parmenides means ... that [the road] they travel is that of investigation according to philosophical reason (τὸν φιλόσοφον λόγον) ... [and that this] reason, like a Divine conductor, points the way to the knowledge of all things" (Sextus Empiricus, Against the Logicians I.112).

Socrates will rely on "refutation" in his love of wisdom.

"While I have breath I shall never give up the love of wisdom (φιλοσοφία) or stop exhorting you, charging any of you I happen to meet in my accustomed manner: 'You are the best of men, being an Athenian, citizen of a city honored for wisdom and power beyond all others. Are you not ashamed to care for money, and reputation, and public honor, while having no thought or concern for wisdom and truth and the best state of your soul?' If some one of you disputes this, and says he does care, I shall not immediately dismiss him and go away but shall question, examine, and cross-examine (ἐλέγξω) him, and if he does not seem to me to possess virtue, and yet says he does, I shall rebuke him for counting of more importance things which by comparison are worthless" (Plato, Apology 29d-30a).

An ἔλεγχος is an "argument of disproof" or "refutation."

Parmenides says that his "refutation" is "much disputed." He does not mean that there is explicit denial that his "refutation" shows what he claims it shows. He means, it seems, that the many (who rely on "experience" for their beliefs) have beliefs inconsistent with his "refutation."
"In no way may this prevail, that things that are not, are. Bar your thought (νόημα) from this way of inquiry, and do not let habit (ἔθος) born from much experience compel you along this way to direct your sightless eye and sounding ear and tongue, but judge by reason (κρῖναι δὲ λόγῳ) the much disputed refutation (ἔλεγχον) spoken by me" (DK 28 B 7).

It can be tempting to think we know what Parmenides means by "reason" and "experience," at least in part because the words are so familiar to us, but we should not assume that the ancient philosophers conceive of these forms of cognition in the same way we do. Parmenides was an early participant in an ongoing project to understand the states and processes in the mind.

The Mistake the Milesians Make

It is in terms of the distinction between the thinking that constitutes "reason" and "experience" that Parmenides seems to criticize Thales and the Milesian inquirers into nature.

Thales and the Milesians rely on "reason" in their inquiries into nature. It is through the use of reason that they try to get beyond the traditional stories involving the gods, but, as Parmenides understands them, they also mistakenly rely on "habit born of much experience."

To explain what "experience" reveals (when it results in the belief that it is raining, that water droplets are forming in the sky and falling to the ground), Anaximenes uses the new style of explanation that the Milesian inquirers into nature introduced. For Anaximenes, air is the underlying nature. Air is. It is everlasting. It never comes into or goes out of existence. At the same time, Anaximenes conceives of droplets of water as portions of air in a condensed state and thinks that these droplets come into and go out existence with changes in the state of air.

This explanation cannot be right, according to Parmenides, because it would follow that drops of water come into and go out of existence and "reason" shows that this is impossible.

Perseus Digital Library:

Henry George Liddell, Robert Scott, A Greek-English Lexicon:
αἰσθάνομαι, aisthanomai, verb, "to perceive, apprehend by the senses"
αἴσθημα, aisthēma, noun, "that which is perceived"
αἴσθησις, aisthēsis, noun, "sensation"
αἰσθητός, aisthētos, adjective, "sensible, perceptible" (opposed to νοητός, "thinkable")

-μα is added to verbal stems to form neuter nouns denoting the result of an action.
αἰσθάνομαι "perceive" → αἴσθημα "that which is perceived."     νοέω "think" → νόημα "that which is thought"

-τός is added to verbal stems to form verbal adjectives (adjectives derived from verbs) that express possibility (or have the meaning of a perfect passive participle). For some discussion and examples, see Symth, 472.
αἰσθάνομαι "perceive" → αἰσθητός "perceivable"

ἀλλοφρονέω, allophroneō, verb, "think of other things"
ἔλεγχος, élenchos, noun, "argument of disproof" or "refutation"
εμπειρία, empeiria, noun, "experience"
ἐπιστήμη, epistēmē, noun, "knowledge"
δόξα, doxa, noun, "belief"
κρίσις, krisis, noun, "judgment"
λόγος, logos, noun, "reason"
πολύπειρος, polypeiros, adjective, "much-experienced"
φρόνησις, phronēsis, noun, "sensibleness [the ability to behave sensibly]"

Arizona State University Library. Loeb Classical Library:
Early Greek Philosophy, Volume V: Western Greek Thinkers, Part 2,

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