One of the founding documents of Western philosophy, Plato’s dialog Phaedo sets forth some of the most important beliefs of Socrates, who shares these ideas with his disciples just before he is executed in ancient Athens. Phaedo is one of Plato’s most widely read works, second only to his Republic and Symposium. It ponders the nature of the human soul and the possibility of an afterlife.

A well-known English translation by Benjamin Jowett is widely available in the public domain; a printed version, which includes a lengthy Introduction by the translator, has been produced. The ebook version of that edition is the basis for this study guide.

Some days after the execution of Socrates, his student Phaedo travels west from Athens to the town of Phlius. There, he meets with a philosopher, Echecrates, who asks about Socrates and what he taught on the day of his execution.

Echecrates heard about the trial through other sources, but he wonders why the execution was delayed for such a long time. Phaedo answers that Athens was in the midst of an annual holy period during which no executions may take place. Echecrates asks whether Socrates was permitted to have friends with him at the end. Phaedo says there were several visitors on the last day, though one of Socrates’s noted pupils, Plato, was away due to illness. As Phaedo shares that the topic was philosophy, and the guests struggled with their feelings: “we were laughing and weeping by turns” (23). He then recounts the conversations that transpired.

The elderly Socrates’s young wife, Xanthippe, is with him, holding one of their children in her arms. She becomes upset that this will be her husband’s last day; Socrates asks that she be taken home. Recently freed of his leg irons, Socrates rubs his sore leg and comments that pleasure and pain go together, and that people chase the one but always must incur the other.

On behalf of his friend the poet Evenus, a guest named Cebes asks why Socrates, long a critic of most music and poetry, is suddenly writing and composing. Socrates replies that he has often had a dream wherein a voice urges him to “compose music,” which he always took to mean that he should continue to do philosophy. Now, at his life’s end, he has decided to take the dream literally.

Socrates suggests that Evenus, insofar as he also is a philosopher, shouldn’t be afraid to follow in Socrates’s footsteps, even to the point of dying, though of course he should not commit suicide. Cebes asks Socrates to explain. Socrates says that a philosopher shouldn’t fear death, nor should he cause himself to die, since people belong to the gods and have no right to take away the gods’ property through suicide. Instead, men should wait until summoned by the gods, who know better than men how to dispense with their lives. In fact, death is a gateway to a better world.

Socrates asks another visitor, Simmias, whether philosophers should pursue the pleasures of life; Simmias replies that they should not. Shouldn’t, then, the philosopher instead be concerned with his soul? Yes, says Simmias. And, insofar as the philosopher studies truth, aren’t the body and its senses unreliable tools in that search? Simmias agrees. And isn’t thought a superior tool, the only one that can possibly understand “true existence”? Yes, says Simmias.

Then how can the search for truth attain its goal as long as the mind is trapped in a body? Thus, “either knowledge is not to be attained at all, or, if at all, after death” (28), and philosophers who spend their lives in ascetic contemplation ought not to shrink away from death when it comes but embrace it.

Most people instead think that temperance is merely a way to make room for better pleasures. In this way they trap themselves more deeply in the swirl of desires, trading resistance against one pleasure for indulgence in another. Philosophers, on the other hand, simply give up all worldly desires for the pursuit of wisdom and virtue.

Cebes worries that the soul is too evanescent to exist by itself, “and that on the very day of death she may perish and come to an end—immediately on her release from the body, issuing forth dispersed like smoke or air and in her flight vanishing away into nothingness” (30).

Socrates replies that if the souls of the dead return to occupy new bodies, then they must, in the interim, dwell in the nether world. But does this actually happen? The answer lies in the “universal opposition of all things” (31). Does not that which becomes great first begin as something small, and things which become small must first be great? And does not sleep follow wakefulness, and waking lead to sleep? Cebes agrees. This principle, declares Socrates, applies to all things: cooling and heating, fast and slow, good and bad, life and death.

Between each opposite there are “intermediate processes” that allow for a transition from one to the other. The living change into the dead, and the dead change into the living, also through a process. This requires that the dead retire to an afterworld from which they will reemerge as new life.

Another argument for rebirth is that all true knowledge is recollection; thus, the remembering mind must have had a previous life to remember that knowledge. Simmias asks for proof. Socrates replies that when people see something, they recognize its category—wood or stone, for example—in its perfection, though no perfect example can be found in day-to-day life. Can this recollection of perfect things have come from our present life? No; it must have come from a previous existence—“That is to say, before we were born”—along with the knowledge of “beauty, goodness, justice, holiness, and of all which we stamp with the name of essence” (34). Thus, before birth, the soul must have had intelligence, even without a body, so it could know the perfect forms that physical things merely imitate.

Simmias and Cebes both argue that though the soul must exist before birth, it still might die when the body dies. Socrates asserts that his previous argument, that birth comes from death, requires that the soul survive death to make possible a birth in the future; this, combined with the human ability to recollect what can’t be learned during life, proves that the soul exists before birth.

Still unsure, Simmias and Cebes ask how they will find answers to these difficult questions after Socrates is gone. He replies that they must search throughout Greece, among its many peoples, and they will find advice on how to ease philosophical worries: “Let the voice of the charmer be applied daily until you have charmed away the fear” (36).

As to whether the soul might dissolve at death, Socrates begins by distinguishing between “compounded” things that have attributes that change and the “uncompounded” things that cannot be so described. He then asks whether things thought beautiful, such as horses and garments, are not always in some way imperfect or changeable, whereas the ideal of beauty is unchanging. His students agree.

More precisely, aren’t the seen things, such as the body, the things that change, while the unseen, like ideals and the soul, are things that do not change? They all concur. Thus, the changeable body will decay after death, while the unchangeable, invisible, undefinable soul continues beyond death. Those souls that are virtuous and seek knowledge in life find themselves in the company of God in the afterlife, to return later either as sociable animals like bees or ants or once again as humans. Meanwhile, souls that fall into gluttony or violence become trapped and anchored to the world and must wander as ghosts until they find an appropriate animal body to occupy, such as an ass (meaning a donkey) or a wolf.

Thus, the good soul abstains from all except the necessary needs, avoids indulging in pleasures, and instead focuses on the “communion of the divine and pure and simple” (41).

Simmias poses the example of the lyre, which generates the lovely harmonies of music when its strings are plucked, but when those strings are cut, the music and harmony disappear. Isn’t the soul similar to the musical harmonies that die when the instrument is broken? Cebes adds an analogy: Just because a coat outlives its weaver doesn’t prove that the coat will last forever.

Echecrates interrupts Phaedo’s report to comment that, after hearing Socrates’s argument shaken by Cebes, he wonders if he ever will hear an argument that can remove all doubt about the soul’s immortality. Phaedo replies that he, too, was stunned by the rebuttal, but he was even more impressed by Socrates’s response, including “the gentle and pleasant and approving manner in which he received the words of the young men” (44), and his willingness to martial his arguments and reenter the fray.

Socrates does so indirectly. First, he comments on Phaedo’s beautiful hair, which the young student intends to shave off the next day as a sign of mourning. Instead, suggests Socrates, he and Phaedo might shave off their hair together, and Phaedo should swear that he won’t regrow his locks until he has found a way to successfully defend Socrates’s ideas about the soul against Cebes’s arguments. Phaedo replies that he will call on Socrates from beyond the grave to help him.

Socrates warns of a hazard. He asks Phaedo if he has noticed that there are very few truly good or bad men; Phaedo says that he has. And are not the vast majority of people somewhere in the middle? Yes, they are. Similarly, most arguments aren’t the very best or worst, and deciding that all arguments are futile just because some arguments fail is like deciding that all people are wicked just because a few are bad.

The philosopher then explains to Simmias and Cebes that he debates them not to win but to defend his ideas until they can prove to him that they’re invalid. Socrates engages in dialog to convince himself much more than to convince others.

He returns to the subject of the soul by asking whether souls can be constructed of things that can fall out of harmony. Simmias agrees that they cannot. Socrates asks whether souls can be distorted in any way, in the manner of human bodies or badly tuned instruments; Simmias says they cannot, and he agrees that souls, as such, can have no blemishes. Socrates adds that the soul often leads the body, directing it to improve its inner harmonies. In this respect, the soul is the arbiter of the body, and not the other way around. Thus, the soul cannot fall apart because it’s not made of things, like harmonies, that fall apart, but instead often guides those things for its own purposes.

To Cebes, Socrates recounts his youthful interest in the sciences and how he became concerned that he could not understand how one plus one could cause two. Then he discovered the philosopher Anaxagoras, whose theories promised to explain the underlying cause and purpose of everything. However, on reading his books, Socrates found a mere accounting of various things that make up the world and descriptions of how they interact, as if that were a sufficient explanation of their causes.

Socrates determined to discover the great truths by carefully thinking about them. He decided that all traits, such as beauty, derive not from themselves but from essential, underlying qualities that impart their characteristics onto objects: “by beauty all beautiful things become beautiful” (52). Thus, things are tall not by comparison but by an absolute quality of size, and other things are large not relative to others but through an absolute “participation” in largeness. Otherwise, Simmias, who is larger than Socrates but smaller than Phaedo, would be at once both large and small.

Another student notes that this argument seems to contradict Socrates’s original statement about opposites and how the large become small and the new becomes old. Socrates replies that the things of the world change in that way, but the ideals—of greatness or beauty or tallness—never change.

Socrates asks Cebes what happens when fire meets snow; they agree that the elements effectively cause each other to depart. Then he asks if Cebes agrees that the odd numbers contain a quality of oddness but are not, themselves, the quality of oddness, Cebes concurs. Three and two have opposite qualities of oddness and evenness, respectively, yet they never cause each other to collapse or melt away. The soul, meanwhile, contains the quality of life, and “the soul will not admit of death, or ever be dead, any more than three or the odd number will admit of the even, or fire or the heat in the fire, of the cold” (56).

Simmias and Cebes agree that Socrates’s argument is sound, but Simmias still entertains a general doubt about the mind’s ability to reach correct conclusions. Socrates says it’s wise to be cautious, and he adjures Simmias always to take great care in thinking and to move forward in his philosophy only when previous assumptions have been proven beyond doubt.

Socrates then quickly sums up his beliefs about the nature of the world. The earth is round and exists at the center of the universe. It is a vast place, and the region in which they dwell is only a small part of the total. We think we can see the heavens above, but, like the ocean’s bottom dwellers who never rise to its surface, we live in the briny hollows of earth and never climb to the edge of the air, where we might find ourselves overwhelmed by the real view of what lies beyond.

Beyond is the earth of the afterlife, more colorful and beautiful and pure than our own, bedecked with gems and gold and jewels, with beautiful animals and people, their lives longer, their senses clearer. Temples there are occupied by the actual gods, who communicate directly with the people. The center of this earth contains channels filled with water and “great rivers of fire” (59), flowing in and out, back and forth, from surface to great depths.

The dead travel underground, where they are cleansed of sins and pay the penalties imposed on them by those they have wronged, but the irredeemably evil are hurled into Tartarus, the center of that earth. The most holy dwell above on the surface—or, if they have purified themselves by the study of philosophy, they live in mansions higher still that are indescribable.

That, or something like it, seems likely to be true, declares Socrates, and the excellence of these rewards makes striving for them worthwhile.

Crito asks how they should bury him. Socrates jests that Crito, who has pledged himself against Socrates escaping, first must make sure he doesn’t run away. That aside, Crito should arrange the funeral as he sees fit.

Socrates retires to bathe, and the others talk among themselves and bemoan their imminent orphanage from their father figure. Socrates’s wife and children return to visit him for a short time.

The teacher rejoins his students. The jailer enters and explains that most condemned men curse him for bringing them poisons decreed by others, but that Socrates is “the noblest and gentlest and best of all who ever came to this place” (62), and that he knows the philosopher will understand. The jailer wishes him well, then bursts into tears and leaves. Socrates calls after the jailer, saying that he will, indeed, follow his instructions.

The jailer brings back the potion. Socrates makes a libation to the gods, requesting a safe journey to the underworld, then he downs the liquid. The students, unable to contain themselves, burst into tears. Socrates jokes that he sent his own family away to avoid such a scene. Per instructions, he walks about until his legs begin to give out, and then he lies down. The jailer presses his feet; Socrates can’t feel them. Soon, he can’t feel his legs either.

As the poison works its way up his body, making it cold, he grows quiet and covers his face. Suddenly uncovering it, he says, “Crito, I owe a cock to Asclepius; will you remember to pay the debt?” (63). Crito agrees, then asks if there is anything else. Socrates doesn’t answer; they look closely and see that he is gone.