Against the Milesian Inquiry into Nature and its Ontology

Elea was a Greek city in what is now southern Italy.

Xenophanes was born in Colophon, a Greek city of Ionia, in about 570 BCE and 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).

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

Parmenides was active in the early to the middle part of the 5th century BCE.

Plato (late 5th century to 347 BCE), in his dialogue Parmenides, indicates that Parmenides visited Athens when Socrates was was a young man and that Parmenides himself was about sixty-five at the time. Socrates was executed in 399 BCE when he was seventy. If Socrates was twenty when Parmenides visited Athens, then Parmenides was born in about 515 BCE.

Nothing comes into Existence

What survives from Parmenides are fragments of poem written in the traditional epic medium of hexameter verse. Parmenides does not identify those he argues against in his poem, but it is natural to understand him to argue against the inquirers into nature and to think that they are confused about what exists. As he seems to understand them, Thales and his fellow Milesian inquirers into nature think that the objects salient in experience exist in terms of changes in the nature of reality.

In his poem, Parmenides argues that this conception of reality is 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 (νοῆσαι); the one, that it is and that it is not possible that it not be (ἔστιν τε καὶ ὡς οὐκ ἔστι μὴ εἶναι), 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 (οὐκ ἔστιν τε καὶ ὡς χρεών ἐστι μὴ εἶναι), this I point out to you is a way altogether indiscernible: for you could not know (γνοίης) what is not (for it is not to be accomplished) nor could you point it out..." (Parmenides, 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" (Parmenides, 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" (Parmenides, DK 28 B 8).
"What birth will you seek for it? How and whence did it grow? I shall not allow you to say nor to think from not being. For it is not to be said nor thought that it is not (οὐ γὰρ φατὸν οὐδὲ νοητόν ἔστιν ὅπως οὐκ ἔστι). And what need would have driven it later rather than earlier, beginning from nothing, to grow? Thus it must either be completely or not all. Nor will the force of conviction (πίστιος) allow anything besides it to come to be ever from not being. Justice has never loosed her fetters to allow it to come to be or to perish, but holds it fast. And the judgment (κρίσις) about these things lies in this: it is or it is not (ἔστιν ἢ οὐκ ἔστιν). But it has been decided, as is necessary, to leave the one way unthought and nameless (for it is no true way), and that the other is and is genuine. And how could what is be in the future? How could it come to be? For if it came into being, it is not: nor is it if it is ever going to be in the future. Coming to be is extinguished and perishing unheard of" (Parmenides, DK 28 B 8).

An Outline of the Reasoning

It is not easy to see just what Parmenides is thinking, but his reasoning seems to take the form of a proof by (what has become to be known as) reductio ad absurdum:

(1) Assume that some object o has come into (gone out of) existence.
(2) It follows that "it is not" is true of o before (or after) it came into (or went out of) existence.
(3) This, however, is absurd: "it is not" can never be true of anything. Otherwise something could both exist and not exist, which is impossible.
(4) Hence, the inquirers into nature are wrong: nothing comes into (or goes out) of existence.

An Analysis of the Reasoning

In this reasoning, the assumption for reductio is that something has come into (or will go out of) existence. The intention is to prove that this assumption leads to an impossibility. From the assumption that some object o has come into existence, it is supposed to follow that o did not exist before it came into existence. This does seem to follow, and this is supposed to be the problem.

It is not very clear, though, just what the problem is. Parmenides seems to think that somehow this is a way of saying of o that "it is not" and that this somehow cannot be true. Parmenides makes suggestive remarks about why this is, but nothing he says is clear enough to be very persuasive given the naturalness of thinking that things do come into and go out of existence.

Knowledge, Reason, Experience

It is not enough to argue the coming into and going out of existence is impossible. Parmenides needs an explanation for why it seems so natural to believe that objects do come into and go out of existence. Widespread beliefs are not always true, but initially at least (both then and now) it seems very plausible to think that many things do come into and go out of existence.

"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 (πολύπειρον) compel you along this way to direct your sightless eye and sounding ear and tongue, but judge by reason (κρῖναι δὲ λόγῳ) the heavily contested testing (ἔλεγχον) spoken by me" (Parmenides, DK 28 B 7).

"In these verses Parmenides means ... that 'the far-famed road of the Daemon' they travel is that of investigation according to philosophical reason (τὸν φιλόσοφον λόγον), which reason, like a Divine conductor, points the way..." (Sextus Empiricus, Against the Logicians I.112).
To this end, Parmenides supposes that in human beings there are various forms of cognition. He supposes that different kinds of cognition are involved in belief formation and retention. He supposes that some of this cognition is properly categorized as "reason," and he supposes that some of this cognition is properly categorized as "experience." His proof is an example of "reason," but otherwise he does not identify "reason" or "experience" with a determinate set of cognitive procedures. He seems instead to understand the contrast imprecisely and in terms of examples.

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

The Mistake the Milesians Make

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 seems to understand them, they also mistakenly rely on "habit born of much experience."

Experience seems to show that sometimes it rains, that sometimes water droplets form in the sky and fall to the ground. To explain what experience shows, Anaximenes uses the new style of explanation that the Milesian inquirers into nature introduced. For Anaximenes, air is the nature of reality. 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.

Perseus Digital Library:

Henry George Liddell, Robert Scott, A Greek-English Lexicon:
αἴσθησις, aisthēsis, noun, "sensation,"
ἀλλοφρονέω, allophroneō, verb, "think of other things,"
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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