Lecture Notes: Plato's Phaedo

UC Davis Philosophy 1

G. J. Mattey

Plato

Plato was one of the most important figures in the history of Western philosophy. In the early twentieth century, Alfred North Whitehead proclaimed that the history of philosophy is nothing more than a series of footnotes to Plato (Process and Reality, p. 39). Plato was an Athenian who was among the followers of Socrates. He left Athens when it became too dangerous following the death of Socrates. After his return, and a subsequent trip to Italy, he founded the Academy, which was the first institution of higher learning in the Western world. Here scholars in all areas of inquiry could pursue their investigations. Plato was known for his utopian political views, which stressed the education of youth. He was offered an opportunity to tutor the son of the ruler of Syracuse, but due to intrigues involving his sponsor there, he was unable to carry out the project. He lived to the age of 80, having been born in 427 BC and died in 347 BC.

Plato's Contributions

Plato is best known for his theory of Forms, to be discussed briefly below. This was a novel attempt to answer Socrates's question about the "what" of things by appeal to special objects which make things what they are. The objects are what they are by their relation to the Forms, a relation Plato called "participation." So just acts are just because of their relation to the Form Justice itself, etc. This led to a division of reality into the divine realm of Forms and the inferior realm of sensible objects. Aside from the theory of the Forms, Plato is credited with the "traditional analysis of knowledge" as true belief with an account (Theatetus). His political views, as detailed in the Republic, will be discussed later in the course. He wrote on many other topics, such as the nature of love. Plato's writings are considered great works of literature as well as of philosophy.

The Dialogues

Plato wrote a number of dialogues between Socrates and his contemporaries. The voice of Socrates is sometimes greater, sometimes lesser, but Plato himself does not appear as a character. The dialogues are are usually divided into three periods. The early period consists of the "Socratic" dialogues, which are more or less accurate accounts of Socrates's philosophical discussions with others in his unsuccessful quests to gain a clear understanding of key concepts, particularly virtue. The works of the early period include Euthryphro, Apology, Crito from our text. Two important dialogues, the Protagoras and Gorgias, find Socrates engaged with the two leading Sophists of his day. In the middle period, Plato developed his own positions. This period is represented by the Phaedo and Republic in our text. He wrote about the theory of knowledge in the Meno (which is in our text but not assigned) and about love in the Symposium. The final period finds Plato wrestling with the significance of his own doctrine of the Forms, particularly in the Sophist and the very difficult dialogue Parmenides. The Theateteus revisits the theory of knowledge. The Timeaus lays down Plato's cosmology. It noteworthy that the Timaeus was the only one of the dialogues that survived in Western Europe up to the Renaissance.

Philosophy and Death

Socrates's imminent execution sets the stage for the dialogue Phaedo. The last pages of the dialogue contain a very moving account of his courageous departure from this life. In the opening pages, Socrates maintains that one aim of practicing philosophy is to prepare for death. The effect of the practice of philosophy is to free the soul from the body as much as possible in life (it being impossible to remain living without a body). What Socrates means is that the soul is freed from the mastery of the body. Because of this adversarial relation with the body, the philosopher is thought by ordinary people as being close to death. The remainder of the philosophical part of the dialogue describes Socrates's views about death, which he was about to face himself.

The Body

The philosopher seeks knowledge, but on Plato's view finds his body to be a great hindrance to his search. Plato was not the first philosopher to call attention to the difficulties posed by human perception. Parmenides had claimed that the entire world of the senses is nothing but illusion, while knowledge can be attained only through reason. Democritus had called attention to the relativity of perception, that is, the fact that virtually any perceptual object appears in different ways from different points of view. Plato endorsed reason the only instrument capable of revealing reality and its truth. For this reason, he is considered one of the earliest "rationalist" philosophers. The functioning of reason is impaired by numerous states of the body (e.g., drunkeness or fever), which is forever in turmoil. Most importantly, it is the body that is the source of needs and desires, and the attempt to satisfy them produces continual disruptive conflicts that interfere with reasoning and hence prevent us from attaining knowledge.

Virtue

The word "philosophy" in Greek means, literally, "love of wisdom" (philo sophia). The philosopher, then, is the lover of wisdom. Socrates contrasts the philosopher with the lover of the body. He maintains that only the lover of wisdom can behave in a way that is truly virtuous. The so-called virtues of the lover of the body are then exposed as fraudulent. For example, a man is said to face death "courageously" when he does not run away in a battle. But there is no courage to his action when he calculates that he has a better chance of avoiding death by fighting the enemy than by running away, in which case he would certainly be killed by his own troops. There is no courage in actions motivated by fear. A person might be moderate in his behavior as the result of a utilitarian calculation. I drink only one glass of wine a night, because it is not very expensive, will probably help my heart, and will not cause a hangover. True moderation would be based on the soul's desire to master the body, not serve other of its needs. Only the philosopher can behave truly virtuously, by despising the body.

Immortality

Socrates had a motive to welcome death, in that he believed that liberation from the corrupting influences of the body would at long last allow him to attain true knowledge. But his soul must survive his death in order for this to occur, and so he needs to convince himself that his soul is immortal. This is not easy to prove, as by its very nature it goes beyond all human experience. (This is why the proof is distinctively philosophical.) As stated in the dialogue, establishing the immortality of the soul requires "a good deal of faith and persuasive argument."

Argument From Opposites

Something can come to be in a state opposite a give state (smaller to larger, weaker to stronger) only if it was first in that opposite state. This is an indisputable truth, but it says very little. Socrates adds that it is through the first opposite that the second opposite state comes to be. There are two opposing states of the body: life and death. So if the living body was at first dead, it came to be alive through death. A body comes to life through its inhabitation by a soul, and it dies when the soul no longer inhabits the body. We can explain how the body comes to life through death by the postulate that the soul that gives life had left a body that had come to die. Here is the argument in schematic form.
  1. Opposites come to be only from opposites
  2. Life is the opposite of death
  3. So, life comes to be through death
  4. Life can come from death only if the soul already exists without the body
  5. The soul exists without the body only due to the death of a previous body
  6. So, the soul exists after death
This argument is quite unpersuasive. Step 1 is ambiguous in the way already explained. If we suppose that a body was once dead and now lives, there is a sense in which life came to be from death. But there is no further reason to think that it became alive through its previous state of death. Indeed, later in the dialogue, Plato explains that opposites in fact recede at the approach of the other. Another problem is with the explanation of how life comes to be through death. The soul is said to have survived the death of a previous body to give life to the current one. So what came to be was life in one body through the death in a different body. But this is not what motivates the "opposites come from opposites" principle. Instead, it is the passing of opposite to opposite in the same thing. A child matures to become larger and stronger. But we do not generally explain the child's becoming larger by means of another child's becoming smaller.

The Forms

At this point, Plato prepares us for a second argument for immortality, based on a doctrine held by Plato but attributed to Socrates here: "learning is no other than recollection." The argument for this position had been laid out in the middle dialogue Meno, in which a slave-boy is induced through Socrates's questioning to prove the Pythaogrean theorem, which he had never learned. In the Phaedo, the doctrine is explained in conjuction with the theory of the Forms. Socrates uses equality as an example. Suppose two sensible objects have the same length, that is, that they are equal to each other. The standard for their equality is the Equal itself. That is, they are equal to each other only insofar as they stand in a relation to the Equal itself. They are not the Equal itself because many other things are equal as well. This reasoning applies to other standards such as the Good itself and the Beautiful itself. What makes object equal, good, and beautiful are called "Forms." They do not exist in the objects to which they apply, but rather exist in a realm of their own.

Recollection

Granted that there is knowledge of the Forms, it must be gained in a way other than through bodily experience. Two objects of equal length can be known to be equal only through knowledge of the Equal itself. On the other hand, repeated sense-experience is never sufficient to inform us of the Equal itself. Plato proposes three explanations for our knowledge of the forms. It might have known the forms once, lost the knowledge, and then recollected it. Since knowledge of the forms is not acquired in life, the only other option is that it is possessed at birth. Either we are born with this knowledge or we come to possess it upon being born. But in either case, everyone would have knowledge of the Forms all the time, which is not the case. (John Locke, writing in the seventeenth century, made a similar point regarding what he called "innate ideas." See An Essay Concerning Human Understanding, Book I.) So the only possibility remaining is recollection. Knowledge of the Forms comes only after appropriate training. The training provides a kind of aid to memory which reminds us of what has been forgotten.

Argument from Recollection

Using knowledge of the Equal itself as a paradigm case, we can now construct an argument for immortality based on the assumption that the doctrine of recollection is correct. The core of the argument is simple enough: in order to recall the forms that are forgotten at birth, the soul must have existed before birth.
  1. The soul can only know the Equal itself by recollection
  2. Recollection requires existence before birth
  3. So, the soul existed before birth
  4. If the soul existed before birth, then it existed after death [from prior argument]
  5. So, the soul exists after death
The central claim of the argument, step 2, appears plausible. But the rest of the argument depends on the establishment of the doctrine of recollection and the previous argument. We have seen that the previous argument is highly dubious. As for the doctrine of recollection, it has been embraced by practically no philosopher after Plato. (It is beyond the scope of these notes to criticize that doctrine here, as we are not reading the main text on the topic.)

Argument from Simplicity

A third argument for the continued existence of the soul after death is based on an analogy between the soul and the Forms. The Forms are not the kind of thing that would cease to exist, because they are not composed of parts. The soul resembles the Forms in various respects, such as being invisible and metaphysically superior, so it probably resembles the form with respect to simplicity as well.
  1. If the soul ceases to exist, it must be because it has decomposed
  2. The Forms are simple and incapable of decomposition
  3. The soul resembles the Forms in its simplicity
  4. So, the soul is incapable of decomposition
  5. So, the soul cannot cease to exist
In the text, we are told initially that it is "likely" that what is not composite will not split up. Plato then shifts the emphasis to the unchanging character of the Forms, eventually declaring them to be incapable of change. The argument could be interpreted as saying that the soul resembles the Forms in some other respects, and by analogy it should be incapable of change as well. But then this would not explain why composition and simplicity are discussed in the first place. I have attempted to integrate the considerations of simplicity with the changeless character of the form. The resulting argument then resembles one that had some currency in the seventeeth and eighteenth centuries, though without the reference to the forms. Simplicity was attributed to the soul on other grounds. Immanuel Kant tried to prove that we cannot know that the soul is simple (Critique of Pure Reason, Paralogisms of Pure Reason). At any rate, step 3 of the argument would have to be established by analogy, and so the argument is not as strong as Plato might like it to be. And it need hardly be added that the existence of the Forms and their divine character is highly controversial.

Purification

At this point, Socrates returns to the theme of philosophy as training for death. The forms exist in a pure, incorruptable realm, and the human soul must be without corruption if it hopes to enter this realm. The state of the soul is determined by the life one has led. The life of the philosopher is one of virtue, as was claimed earlier. The life of the lover of the body is polluted, and the soul of such a person will be unhappy. Plato indulges in talk of reincarnation, according to which the animal form which the soul takes on is appropriate for the kind of vice that corrupts it. The philosopher can avoid this kind of end through a process of purification, which eventually leads to true knowledge. Preparation for death, then, is purification.

The Harmony Objection

Returning to the theme of the soul's continued existence after death, Plato considers two objections, one by Simmias and one by Cebes. Simmias's objection is based on a conception of the soul that distinguishes it from the body but at the same time allows for its ceasing to be. This is the Pythagorean conception of the soul as a harmony. Its relation to the body would be like that of harmonious notes played on a lyre (a stringed instrument of ancient Greece). When the lyre ceases to exist, the harmony does as well. So if the soul is the harmony of the body, it would cease to exist when the body dies (which might be like the strings' becoming slack). It is pointed out by Socrates that this account of the soul is incompatible with the doctrine of recollection. A harmony is formed after the tuning of the strings of the lyre, and so the soul would have to come to be after the body has developed. Moreover, Plato sought in the Republic to model virtue and vice on harmony and disharmony, respectively. If the soul is a harmony, virtue would have to be a harmony of a harmony, which makes no sense. For these two reasons, the harmony account of the soul is rejected, and the threat it poses to immortality is dispelled.

The "Cloak" Objection

Cebes's objection points out a weakness in the first and second arguments. If the soul exists in a body now, it must have existed before it entered that body. Suppose we grant that it requires that it survived the death of a previous body, and even many previous bodies. This, Cebes says, is like a human body outliving many different cloaks, which eventually wear out. Still, when a body dies, it may be wearing a cloak which will outlast it. So the body a soul inhabits right now may be the last body it inhabits. That body would survive as a corpse for a while after the soul has ceased to exist. What is there to prevent this?

Admitting the Opposite

Socrates says that he has to make a digression about the causes of generation to answer this objection. (He might have noted that the simplicity argument is not vulnerable to it, but as we have seen, that argument is not very strong, because it is based on an analogy.) Change is explained through the Forms. A thing becomes the kind of thing it does because of its relation to the forms. If a man who is unjust becomes just, it is because in some way Injustice itself recedes as Justice advances. Justice does not become Injustice, because Forms cannot become their opposites. The Odd can never become the Even, and vice-versa. Moreover, what is related to a Form necessarily cannot take on the opposite Form. The triad is necessarily related to the Odd, and it cannot admit the Even.

The Final Argument

Now Socrates is in a position to construct the final argument for immortality. The soul is like the triad. It is necessarily related to Life, because it can only bring life into the body it enters. And so it does not admit its opposite, Death. This makes the soul deathless, and what is deathless cannot be destroyed.
  1. The soul can only bring life to the body into which it enters
  2. So, the soul does not admit the opposite of life
  3. The opposite of life is death
  4. So, the soul never admits death
  5. So, the soul is deathless
  6. What is deathless is indestructible
  7. So, the soul is indestructible
This argument meets the "cloak" objection raised by Cebes. It is not very satisfactory, though. Suppose we grant the first step, does the second follow? The fact that the soul brings life to the body does not mean that it is itself necessarily living. It might be that, so to speak, death can be brought to it, though it cannot bring death to something. And the argument also depends on making Death a form opposite to Life. It is plausible to suppose that death is nothing positive, like the Even or even Injustice (as found in acts of murder). Death may well be simply the cessation of life.

The Underworld

Socrates sweetens the thought of his death with an elaborate description of the world, including the underworld and a divine resting place for the virtuous. The wicked are punished repeatedly by being washed down rivers again and again, until they are finally purified. The virtuous rise to the surface of the earth, to a beautful place where they can gain the knowledge that eludes them in life. Socrates soon hopes to join the blessed souls who are finally enjoying the best condition attainable by a human being. He takes the poison himself, courageous in the way that only a lover of wisdom can be.
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