The evidence. At 17b16–20 Aristotle discusses contradictory pairs where one member is a universal predicative assertion. Here is the text handed down by the main manuscripts and printed by the majority of recent editors (Bekker, Waitz, Dübner, Cooke, Minio-Paluello, and Zadro):

Ammonius (in Int. 109, 24–5) reports that according to Porphyry at 17b17 some manuscripts instead of ‘ἀντιφατικῶς’ read ‘ἀποφαντικῶς’ (some manuscripts of Ammonius have ‘ἀποφατικῶς’, the reading we find also in some manuscripts of de Interpretatione, e.g. in Laur. 72, 17). In n ‘τῷ’ (17b17) is added above the line. Bekker claims that at 17b17–18 B reads ‘τὴν τὸ καθόλου σημαίνουσαν τῇ τὸ οὐ καθόλου’, but he is wrong: B's reading is the same as that of the other main manuscripts. (Was this reading attested in some other manuscript?) At 17b18 Laur. 72, 4 omits the first ‘οὐ’. In Vat. Palat. Gr. 74 a later hand added ‘τῇ τὸ αὐτὸ’ above ‘τῷ αὐτῷ’.

The evidence. At 1051b1 the main witnesses present a variety of readings: Ab and (probably) ps.-Alexander (in Metaph. 598, 1–2) have ‘κυριώταταὂν’; the first hand of E has ‘κυριώτατον εἰ’; J and the second hand of E have ‘κυριώταταεἰ’; William of Moerbeke's translation presupposes ‘κυριώτατα ἢ’.

Brandis, Bekker, Weise, Schwegler, Bonitz, Dübner, Christ, and Jaeger print ‘κυριώτατα ὂν’. Ross (followed by Tredennick and various commentators) excises ‘κυριώτατα ὂν’ (he also contemplates the possibility of transposing it after ‘τὸ μὲν’ at 1051a34). Jaeger suspects a lacuna between ‘κυριώτατα ὂν’ and ἀληθὲς ἢ ψεῦδος’: he suggests ‘κυριώτατα ὂν <ἡ οὐσία, λείπεται δὲ ἐπισκοπεῖν τὸ ὂν> ἀληθὲς ἢ ψεῦδος’.

An inconsistency? Many editors and commentators find the reading ‘κυριώτατα ὂν’ of Ab at 1051b1 hard to accept because in Metaphysics E 4 (= T7), at 1027b31, Aristotle says that what ‘is’ in the sense of being true ‘is a different thing that “is” from the things that “are” in the strict sense [κυρίως]’: were the reading ‘κυριώτατα ὂν’ genuine, in Metaphysics Θ 10 Aristotle would be committing himself to the incompatible claim that what ‘is’ in the sense of being true is what ‘is’ in the strictest sense. The fact that E 4, at 1027b28–9, contains a forward reference to Θ 10 makes it particularly implausible to assume that Aristotle should entertain such incompatible views about what ‘is’ in the sense of being true.

As we saw in chapter 4, Aristotle's theory of truth for assertions can be regarded as a correspondence-as-isomorphism theory of truth: Aristotle takes an assertion's truth to consist in a certain isomorphism obtaining between the assertion and reality. We also saw that Aristotle's correspondence-as-isomorphism theory of truth presents itself in two formats. In the first, the components of reality with respect to which a true assertion's isomorphism holds are objects that correspond to assertions as wholes (one object corresponding to one complete assertion). In the second format, which concerns mainly predicative assertions, the components of reality with respect to which a true predicative assertion's isomorphism holds correspond to parts of the assertion: they are objects, i.e. universals or individuals, signified by the assertion's predicate and subject. A well-known difficulty faced by correspondence-as-isomorphism theories of truth of the second format is the problem of ‘vacuous’ terms. What happens if either the subject or the predicate of an assertion is ‘vacuous’, i.e. fails to signify an item of the appropriate kind? A correspondence-as-isomorphism theory of truth of the second format loses one of its toeholds.

Section 1 contains four arguments for the thesis that Aristotle's reply to the problem of ‘vacuous’ terms is that in every predicative assertion both the predicate and the subject are ‘non-vacuous’ in that they signify items of the appropriate kinds.

This chapter addresses the relationship of truth to time and change. According to Aristotle, any bearer of truth or falsehood can, at least in principle, be true at one time and false at another. This is somewhat hard to square with his view that the linguistic items that are bearers of truth or falsehood are utterances (expression-tokens). On reflection, however, the position turns out to be consistent: utterances (expression-tokens) can be true at one time and false at another.

Aristotle also claims that if an assertion or a belief is true at one time and false at another, it does not follow that it undergoes a change. This is probably due to the idea that truth (being correspondence to the world) is something like a relative and therefore, like relatives, is involved at most in a ‘mere Cambridge change’ that does not count as a genuine change. Now, properties involved in a ‘mere Cambridge change’ are not genuine properties. It follows that truth is not a genuine property.

DIFFERENT TRUTH-VALUES AT DIFFERENT TIMES

Truth and falsehood at times. Aristotle thinks that the bearers of truth or falsehood are true, or false, at times. He does not formulate this view explicitly: nowhere does he use a sentence like ‘States of affairs, beliefs, and assertions are true or false not absolutely, but at times.’

There are lots of divisions among Plato scholars, but two of the biggest are these.

Some think that Plato's dialogues proceed from a single view throughout: that there is no question of a development in Plato's thought. Their opposite numbers think that there is development to be seen in the dialogues. The first view is sometimes referred to as “unitarian,” and the second could be labeled “developmental.”

Then again, some scholars see in the dialogues dramatic creations, and so the technique they favor in understanding them is literary analysis. Their opposite numbers see in the dialogues a lot of abstract argumentation, and so their favored technique is that of logical analysis. The first of these two approaches we may call “literary,” and the second “analytic.”

This latter opposition would be unreal if either position were understood as exclusive of the other: obviously the dialogues contain both drama and argument. The question of which approach to take is, then, one of emphasis. But there are extremes, and the extremes are in opposition.

This book is a defense of a developmental view with an analytic emphasis.

It is confined to the dialogues commonly regarded as early plus the Phaedo and Symposium, and to what in those latter dialogues pertains to a certain metaphysical theory, commonly referred to as the “Theory of Forms.”

Socrates, Aristotle says, was the first to fix attention on definitions, and the Socrates of the Socratic dialogues does that. But he does not simply say: let's define (say) piety. He doesn't have the word “define”: this is discussed in § 2.1.

Nor does he simply look for definitions as an abstract intellectual enterprise. He expects definitions to solve certain problems. So we must look at the problems (§ 2.2), and at the reason Socrates thinks definitions are required for solving them (§ 2.3).

PRELIMINARY: ON THE VOCABULARY FOR “DEFINING”

The Socratic dialogues do not consistently employ terms for “define” or “definition.” Aristotle has a technical terminology here, but this is after the arteries have hardened considerably. Some of his words appear in the Socratic dialogues. His favored noun, ʿορισμός, does not appear anywhere in Plato, but an alternative, ὅρος, does, as does the associated verb ʿορίζειν. All these words have to do originally with (spatial) boundaries, and the transition to technical philosophical terminology is only just under way in the Socratic dialogues. Of the six occurrences of ὅρος in these dialogues, that in the first book of the Republic is the one for which the translation “definition” is the most comfortable. There Socrates, having raised the question (331c1–3) “whether we are to say that this itself, justice, is, without qualification, truthfulness and giving back what one has taken from someone,” gives a counterexample, and says (331d2–3): “So this is not {a} definition of justice, saying the truth and giving back what one has taken.

The Socrates of Plato's Socratic dialogues was in quest of definitions because he thought they were required for living right: he supposed that in order to know whether certain actions were courageous, or pious, or admirable, one must know what the courageous, the pious, and the admirable are.

We laid out a theory of definition for Socrates: not necessarily his or Plato's own theory, but one based on the refutations of definitions in Plato's Socratic dialogues. The theory had three main components: the Substitutivity Requirement, the Paradigm Requirement, and the Explanatory Requirement.

The Explanatory Requirement, at first blush, simply demanded that one be able to use the definition for the pious in explaining why one called a given action (or person) “pious”: it was a matter of explaining content. But there turned out to be more to it than that: it was required that what one introduces and defines as the pious be itself indelibly pious. That connected the Explanatory Requirement with the Paradigm Requirement. And both were connected with the Substitutivity Requirement, construed as the demand that what is defined as the pious give necessary and sufficient conditions for something's being pious.

That theory has now turned into the Theory of Forms. Substitutivity is obvious enough: the things that partake of the Form, The Pious, have to be all and only the actions and people that are pious. The Paradigm Requirement is now the claim that the separate Form, The Pious, is through and through pious.

Socrates expects satisfactory definitions to do some sort of explanatory job. At the most elementary level, this job is that of what I shall call “explaining content.” I'll start by explaining the content of that phrase, and then, after yet another look at Euthyphro 6de, turn to one passage in which a definition is failed because it does not explain content: Euthyphro 9d–11b.

EXPLAINING CONTENT

Consider the following dialogue schema:

1. Q1: What's that?

2. A1: It's an F.

3. Q2: Why is it an F?

4. A2: Because it is H, and F=df the H.

At a minimum, Socrates expects someone with a proper definition for courage, piety, or whatever, to be able to use it in the way A does here.

Consider Q2. It is vague: it may have different forces in different contexts.

It might be that Q is not a native speaker of English, A knows this, and uses “G” to define “F” on this occasion because he knows that the words that compose “G” are English words known to Q. He might define “F” quite differently for another speaker. If Socrates were only requiring this much of definitions, it would just be a question of explaining the content of a term in a way that would make the use of the term comprehensible to a given audience.

Plainly Socrates wants more: he expects the correct definition to explain the content of the term on every occasion in which explanation is demanded.

To say that x is F because of the F or Fness is elliptical or incomplete: the relationship between x and the F by virtue of which x is F remains unspecified. The Socratic dialogues we are examining are quite unselfconscious about that relationship, by contrast with Phaedo 100cd, where we shall find Socrates using a variety of terms for the relationship between a Form and the things here below that partake of it and expressing a studious indifference about which is the right one. Back where we are, he also uses a variety of terms for the relationship between the F and the things that are F. He does not say much about this variety of terms (but see §§ 8.2.3 and 8.2.4.1). He frequently speaks of the relationship as one of presence: temperance is-present-to someone or something (παρει̃ναί τινι); common variants have the virtue or character being-added-to (προσγίγνεσθαι) or being in (εἶναι ʾεν or ʾενεῖναι) that which has it, or of someone or something as partaking of or getting a share of (μετέχειν) that virtue or character.

Does this mean that Socrates has in these dialogues a theory of forms according to which they are immanent in things? Well, he talks of forms, and he talks as if they were present in things. But does he have a theory, or is he just talking that way?

In every dialogue apart from the Parmenides in which the Theory of Forms puts in an appearance, the main topic is something else. In the Phaedo it is immortality: the Forms are used in three arguments for the immortality of the soul. But they make a separate entrance before that.

64C: AN EXISTENTIAL ADMISSION

Socrates defends his readiness to die beginning with the question (64c2) “do we think there is such a thing as death?” (ἡγούμεθά τι τὸν θάνατον εἰ̃ναι;). He immediately says what death is (c4–5): “the release of the soul from the body” or the “coming-to-be in separation” of soul and body (c5–8). He now argues that the philosopher, whom he portrays as ascetic, is engaging in separating his soul from his body (64c–69e).

Socrates' question at 64c2 concerns an existential claim to which Simmias' assent commits him. It is, once again, a topic-fixer: Simmias is only conceding that people sometimes die; he is not committed by his concession to the Theory of Forms. It is a clear implication of 105d9, d13–14, etc., that there is a Form for death. But it is only in retrospect that we can say: in 64c, Simmias had already acknowledged the existence of the Form, Death; that is like saying that someone who has acknowledged the existence of the number 13 has committed himself to the existence of a prime number, or to the existence of a positive root of the equation “845 + 1183x ⊟ 96x2 = 0.”

The Paradigm Requirement and the Explanatory Requirement are ultimately fused, and that fusion brings in some extra baggage. The anemic interpretation of the Explanatory Requirement may be all that is needed for the use to which it is put in the Euthyphro, but that is not true of all the passages in which we encounter it.

In the early dialogues, Socrates occasionally imports a presupposition about what can explain something's being F to the effect that what makes things F must itself be F; it makes things F by transmitting its Fness to them. This is the beginning of a theory of causality. Let us call any theory that employs this presupposition a “Transmission Theory” of Causality. The cause, whatever it is, is a “transmitting cause” of other things' being F.

The Theory of Forms is going to incorporate a Transmission Theory of Causality: the Form, the F, will make things F by transmitting its own being F to those things. The Theory of Forms is not unique in this: Aristotle will also advocate a Transmission Theory of Causality, especially in the domain of biology (ἄνθρωπος ἄνθρωπον γεννᾷ: it takes a human being to generate a human being), without Plato's Theory of Forms (Aristotle does, of course, have a theory of forms). So accepting a Transmission Theory does not commit one to Plato's Theory of Forms.

In Aristotle, we may distinguish between two grades of Transmission Theory: a Strong one and a Weak one.