Though the Phaedo's death scene forges a dramatic connection with early Socratic dialogues such as the Apology and Crito, the Phaedo is quite different from these Socratic dialogues. Unlike the Apology (29a, 37b, 40c), the Phaedo is not metaphysically agnostic; Plato embraces psychophysical dualism and the immortality of the soul. The Phaedo also contains bolder claims to knowledge and theory construction than the Socratic dialogues. And, unlike the Socratic dialogues, the Phaedo denigrates the senses. Finally, the Phaedo is also thought to inaugurate the theory of separated Forms.
FLUX AND FORMS
According to Aristotle, Plato separates the forms, whereas Socrates does not (Metaphysics 987a31-b10, 1078b12-79a4, 1086a30-b7).
Socrates ... was concerned with ethics and not at all with nature as a whole; he was seeking the universal in ethics and was the first to turn his thought to definitions. Plato agreed with Socrates, but because of his Heraclitean views he took these definitions to apply not to perceptible things but to other things; for, he thought, the common formula could not be any of the perceptible things, since they are always changing. Beings of this sort, then, he called Ideas, and he said that these sensible things were separate from them ... [987a31-b9].Here Aristotle claims that it was the search for definitions and knowledge that led Socrates to forms and that it was Plato's belief in the Heraclitean doctrine of sensible flux that led him to posit separated Forms. According to Aristotle, whereas Plato separated the forms, Socrates did not. (We will return to the issue of separation below.) It is in Plato's Phaedo that we first encounter arguments for forms that appeal to sensible flux. The argument goes something like this (74a9-c5).
Plato's main claim is that sensible properties contain both F and not-F instances. In general, there is no reason to think that he believes that sensible particulars are both F and not-F. Presumably, particular actions are not both just and unjust. It's rather that in some cases returning what is owed is just, and in other cases it is not. However, in cases involving relational properties Plato does think that sensible particulars can have contradictory properties. Simmias is both tall (compared to Socrates) and short or not-tall (compared to Phaedo) (102b-d). And Helen is both beautiful (compared with mortals) and ugly or not-beautiful (compared with gods) (Hippias Major 289a-e).
Does flux generate forms for all properties? In the Republic Plato seems to deny that the senses are inadequate for fingers (523a-525a). But presumably he recognizes a form for fingers and thinks that these forms are necessary for knowledge of fingers. Or does he? Plato seems to have a problem if he makes all of the following assumptions.
ONE OVER MANY
Where he recognizes a form for bee and bed, and elsewhere, Plato appeals to the One over Many Assumption (OMA), as well as flux, in generating forms. This assumption is equivalent to the unity assumption, already at work in the Euthyphro. There are two main questions to ask about the interpretation of the OMA.
Are there forms (a) corresponding to every possible universal, or (b) only for natural kinds? Endorsing (b) Aristotle criticizes Plato for endorsing (a). But it is not clear that this is Plato's view. The Statesman claims that there is no form for barbarian (barbaros), because it signifies non-Greek (262a). The Cratylus suggests that names must signify genuine individuals or kinds. The Parmenides suggests that there may be no form for mud, dirt, and hair (130c5-d5).
How are forms generated by the OMA relevant to knowledge? The OMA appeals the form of F as what is common to all and only F-things and as what explains what makes F-things F (combining unity and explanatory requirements). It is possible to think of forms, understood and generated in this way, as helping Plato defend the Meno's account of the difference between knowledge and true belief (97a-98a). Knowledge is true belief tied down by an account. Though true belief is just as useful as knowledge, insofar as one has either, knowledge is more stable than true belief, because it ensures true belief in a wider range of circumstances. I might have the true belief that the golden colored minerals in my pouch are gold. But if I don't know what makes them gold, then I won't form true beliefs in other contexts, for instance, when I come acroos fool's gold (iron pyrite). For then my failure to understand what makes my gold gold (why my true beliefs are true) will lead me to form false beliefs in other situations, for instance, those in which I have only iron pyrite in my pouch. And this suggests that in the actual situation in which I do have true beliefs, this does not yet count as knowledge. For these true beliefs to count as knowledge, they must be based on the right account of what makes my samples of gold gold (perhaps something about their having the right atomic number).
The relevance of OMA generated forms to knowledge, is that this sort of account is necessary to secure the sort of counterfactual, and not merely extensional, reliability that is necessary for knowledge, as opposed to true belief (cf. Irwin, Plato's Ethics, ch. 9). But this argument dovetails with considerations of flux insofar as the flux argument claims that sensible accounts of the forms also lead to counterfactual, if not extensional, unreliability. In effect the OMA shows why flux should generate a wider range of forms, including forms for fingers and cats. This means that Plato probably should reject (4) as well as (6).
We saw that Aristotle says that Plato separates the forms, whereas Socrates does not (Meta 987a31-b10, 1078b12-79a4, 1086a30-b7). To understand and assess this claim we need to fix ideas. Following Gail Fine, we might understand separation as the capacity for independent existence.
DOES PLATO SEPARATE THE FORMS?
Interestingly, Plato does not apply the Greek term for separation -- "choris" or its cognates -- to forms in the middle period dialogues such as the Phaedo or Republic. Of course, it still might be true that he commits himself to separating the forms. Does he?
The Flux argument requires that we distinguish forms and sensible properties -- it is a contrast between two different sort of properties or universal. That does not imply anything about the relation between forms (nonsensible properties) and sensible particular. A fortiori, the Flux argument does not entail that forms could exist independently of sensible particulars.
The OMA requires only that there be a form of F of which the many F-things partake. This doesn't require that F be able to exist independently of the many F-things.
In the Republic Plato suggests that forms are paradigms or ideals. Plato may believe, like Aristotle, that natural kinds (e.g. species) are eternal and immutable, so that there have always been instances of these kinds and forms. However, presumably he does not think that artifacts have always existed. He recognizes forms for artifacts, such as beds (596b). If a craftsman fashions the first artifact of a given kind by articulating and following a paradigm, then the form of F can predate the first F-thing. However, it may not be clear if the blueprint for an artifact constitutes its form.
DOES SOCRATES SEPARATE THE FORMS?
Some (e.g. Fine and Irwin) have been willing to question the reliability of Aristotle's testimony about whether Plato did in fact separate the forms. However, few seem to question Aristotle's testimony about Socrates. But that too deserves scrutiny.
First we should distinguish stronger and weaker claims that Aristotle might be making about Socrates. He might mean simply Socrates was agnostic about separation.
However, there is an interesting case to be made that Aristotle is wrong even if he says only that Socrates did not separate the forms (and does not say that he denied that they were separate). There are two ways one could separate the forms. One could endorse the weaker claim about that it is possible for forms to exist uninstantiated.
But this reply assumes that there can be virtuous actions if there are no virtuous persons. But this assumption is suspect. Socrates can and should distinguish between actions that conform to virtue and those that express virtue. Genuinely virtuous actions must not merely conform to the requirements but must express a virtuous character. If so, we should not allow that there are virtuous actions if we concede that there are no virtuous people.
The Phaedo accepts psychophysical dualism and the immortality of the soul. One of Plato's arguments for these conclusions is the theory of Recollection from the Meno, though it is not defended at as great a length nor explicitly connected with the paradox of inquiry, as it was in the Meno (Ph 72e3-77a5). Recollection is conceded by Simmias and Cebes, but Cebes wants to be shown that the soul will persist after death as well as before birth (77c1-5). Socrates has two replies.
First, Socrates reminds him of the argument from coming to be: things come to be only from their opposites (70d7-). Just as death must come to be from living, so too living must come to be from death. We know by this principle that x's life came to be out of death or non life, and Recollection implies that this death or non life came to be out of a previous life. Thus, Socrates concludes, we're justified in believing in a kind of "eternal recurrence" (77c7-d5).
Second, Socrates recognizes that this argument may not satisfy (though he doesn't indicate why) and offers another argument (78b4-).
Socrates does not consider these worries, but he does consider two objections to his defense of immortality: Cebes's Cloak objection and Simmias's Attunement objection.
ATTUNEMENT (85e-87a, 91e-95a)
Is the soul an "attunement" of the body that is not itself a bodily component and cannot survive the destruction of the body (85e-d)? Socrates expresses two objections to Attunement.
(1) He claims that Attunement is incompatible with Recollection (92a-93e). Is this true? Might an attunement persist across lyres/bodies? If my son's cello is tuned on the basis of the attunement in his teacher's cello, then perhaps her attunement migrates. If so, then Attunement, as such, is not incompatible with Recollection but neither does it undermine immortality. One issue is whether (a) Recollection implies that the soul is always embodied but occupies different bodies over time or whether (b) it implies that the soul is disembodied at some points. If attunements can migrate from instrument/body to instrument/body, then (a) implies that Attunement is compatible with Recollection. But then it's equally true that Attunment ceases to be an objection to immortality, because the soul/attunement can survice the destruction of this body. But Socrates may assume that Recollection involves (b), inasmuch as he thinks that death promises to liberate his soul from the corrupting influences of the body. But if Recollection is committed to (b), the Attunement is incompatible with Recollection, and we must choose between them. One question here is whether Recollection has been defended in its metaphysically robust, non-deflationary form. If not, we might prefer Attunement to Recollection.
(2) Socrates also asserts that attunement can be a matter of degree, whereas being ensouled cannot (93a-e).
CLOAK (87b-88b, 95a-107a)
Even if the soul has outlived many bodies, will it outlive the present one? Perhaps Socrates's soul stands to his present body the way the weaver stands to his last cloak; he outlasts many cloaks but not the one he dies in (86e-88b). Plato's reply is complicated and involves further claims about forms and formal explanations (96c5-105c8). The main claims, for our purposes, are these.
(a) The inference from (3) to (4) seems to ignore Plato's earlier claims about the relation among opposites.
snow will never ... admit the hot and still be what it was, namely snow, and also hot; but at the advance of the hot, it will either get out of the way or persih [103d5-8].True, the soul will never admit death and continue existing; it must either go elsewhere (immortality) or perish. It's not clear why Plato is entitled to assume the first possibility and ignore the second. When we apply the hair dryer to Frosty the Snowman, he must either perish or get out of the way. Presumably, he perishes.
(b) Does Plato assume that the form of soul will persist, because forms are eternal? But what is the relationship between my soul and the form of soulhood? should I feel comforted by knowing that the form of soulhood persists if my soul does not? Does Plato assume that it is just my embodied existence that distinguishes me from other souls -- that my soul is just a particular instantiation of some generic universal soul? When Frosty melts, he dies. Perhaps the form of Snowman does not die (so long as there are other snowmen, if Plato does not separate the forms, and in any case, if he does separate the forms). But this might seem like cold comfort to Frosty.
(c) If all souls are just different instances of soulhood, is Plato in a position to recognize the existence of individual, qualitatively distinct souls? If not, what are we to make of Plato's idea that there will be differential rewards for qualitatively different souls?