Skip to content

The Republic

Book I - Defining Justice

Socrates is walking through Piraeus with Glaucun when Polemarchus spots him and invites him to his house. Cephalus, Polemarchus' father, opens a discussion about old age and wealth.


Socrates asks him what good can come from an accumulation of wealth such as his. As Cephalus puts it, despite the disposition of his youth, once a man reaches old age and faces the reality of death he will inevitably be haunted by any injustice in his past. A healthy amount of wealth at this stage allows one to pay off the debts he has thus far incurred.

Cephalus implies here that justice is simply the repayment of debts, which Socrates has issue with. Cephalus leaves and we move from the fiscally transactional definition of justice to a more social definition involving the interactions between friend and foe.


Polemarchus propounds that justice is to "treat a friend well, provided he is good, and to harm an enemy provided he is bad" (335a10). This implies that malice, knowingly harming another person, is an essential part of justice which naturally seems wrong. Upon concluding that this cannot be the case Thrasymachus (of Chalcedon, who simply "happened to be there too") abruptly and rather feverishly usurps the conversation.


After some bickering we finally hear his belief that justice is what is advantageous to the stronger (338c). In other words, a ruler "decrees what is best for himself, and that is what his subjects must do" (341a). This seems to be a bit of an abstraction upon his more fundamental belief on justice which is extracted later in the elenchus.

For now, Socrates decides to dive into the definition of craft. A craft has a single virtue and through this virtue improves upon a single object (in the form sense) and necessarily does not improve upon itself. If the craft of medicine desired to make any improvements upon itself, a new craft must be developed with a new virtue and who's sole object is medicine. By this logic we can conclude that "no one in any position of rule, to the extent that he is a ruler, considers or enjoins what is advantageous for himself, but what is advantageous for his subject—that on which he practices his craft."

After this dialectic Socrates has finally aggravated Thrasymachus enough to invoke a speech in which we learn what he truly believes about justice. What Thrasymachus means to say is that to be unjust is to take from others, while the just do not. Essentially that injustice is more profitable than justice, and surprisingly that unjust people are wise and good and just people are ignorant and bad.

This is refuted by attacking the principle that the unjust want to do better than those similar and different to themselves. A good and wise person does not want to do better than those like himself, but rather those different and opposite to himself. Thus a just person is like a wise and good person, an unjust person the opposite.

Unity and cooperation within a society is not possible without justice, as injustice causes faction and quarrels.

Apparently, then, its power is such that whenever it comes to exist in something—whether in a city, a family, an army, or anything else whatsoever—it makes that thing, first of all, incapable of acting in concert with itself, because of the faction and difference it creates; and, second of all, an enemy to itself, and to what is in every way its opposite: namely, justice.


Everything has a virtue that allows it to perform things well, and by means of an opposite vice it performs things poorly. Justice is a soul's virtue, and this through justice it will live well and happy and profitable.

Book II

  • Socrates argues justice is a good that is loved for it's own sake and it's consequences, but Glaucon argues it is a burden on it's own, but it's consequences are valued
  • Glauon's speech
    • What is justice and it's origins?
      • It is said that it is good to to injustice and bad to suffer it, but the badness suffered far outweighs the goodness gained. Thus those who have experienced both conclude that it would be best ("profitable) for everyone as a whole to simply refrain from injustice completely. As a result laws and rules are put in place to enforce such equality or "justice"
    • Those who practice it do so unwillingly
      • Ring allegory
        • When someone believes they can do injustice with impunity we can rely on the fact that they will
    • They have good reason to do so
      • We are given a situation where one man is unjust but crafty as to disguise his being as a just one
      • Another man next to him is the opposite, completely just yet perceived as unjust
        • Here Glaucon says this is a requirement so that "he may be tested with regard to justice by seeing if he can withstand a bad reputation and its consequences" although this doesn't seem quite fair. The unjust man is able to live with his actions in the peace of a good reputation, why can the just not do the same?
      • We will see which is happier
      • In such a case, the just will realize that what he wants is not to be just but so solely be perceived as just
  • Adeimantus
    • We should look at the arguments in favor of justice as well
    • fathers tell their sons to be just, but the inducement is not justice itself but rather the consequences of a just reputation
    • poets and gods praise the just
      • the gods either do not care about us, or on the faith of the poets and laws the do care for us and can also be "persuaded by sacrifices, gentle prayers and offerings".
      • if this is to be believed, then we should be unjust and offer sacrifices from the profit
      • if they are not to be believed, there is nothing to fear from this behaviour
    • the most important question arises
      • This is what I want you to praise about justice. How does it—because of its very self—benefit its possessor, and how does injustice harm him?

  • Socrates propounds that we should investigate cities then, for there we will find the largest example of justice and thus it will be easier to analyze
  • cities exist due to the codependence of man through specialization
  • The city starts small, the barest city consisting of only 4 or 5 men
    • we are not all born alike. On the contrary, each of us differs somewhat in nature from the others, one being suited to one job, another to another.

    • one must focus on a single thing and be ready for the precise opportune moment of execution in any job or the work will arguably be spoiled. Following this will result in better quality and more plentiful goods
    • the city grows in size luxuries and dependencies as we continue to add functionality and further luxury
    • once we have value (which is beyond the bare city ideal of Socrates) we now have value that others may desire to take
    • And won’t our neighbors want to seize part of ours in turn, if they too have abandoned themselves to the endless acquisition of money and overstepped the limit of their necessary desires?

    • in the same vain, a population of specialized guardians must be created
      • gentle to those they "know", aggressive towards the opposite
      • to value and protect what you know is purely philosophical (lover of knowledge and learning)
      • phyiscal training and education of the guardians will be delicately contrived to create the perfect protector
        • they must love each of their citizens as family and have no notion of violence or evil done against a filial relationship
      • gods are and should be depicted as the paradigm of good, nothing else could be god like at all

Book III

  • types of lies (389b)
  • Redefining how the gods are depicted in literature to stop inculcation of untrue lessons about the world (391a)
    • Gods are good and thus should embody pure goodness rather than the human nature Homer applies onto them
  • after the gods we must look at what is left, the prose and poetry about humans
    • justice is virtuous, but in order to come to an agreement about what stories should be told in order to teach this again we must be able to understand what justice is and how it affects the actor
  • should we allow poets to narrate as imitators? if so for what?

an individual can neither imitate many things well nor perform well the actions themselves of which those imitations are the likeness of 395b5

  • An actor or writer of comedy is imitating comedy, but cannot perform the action of comedy itself well? What is this particular action then?
    • possibly the organic production of genuine comedy compared to the imitation of a comedic act with style
  • A guardian must not do or imitate anything which does not fall under the umbrella of his duties. They may know about such things but to imitate is to allow oneself to become another thing and this can create habits.
  • All craftsmen, like we discussed in the poets who should be compelled to "embody the image of good character", must work to attain the virtue of their craft and their craft only (401b)
  • we cannot know a thing until we understand the principles of that thing, and we cannot know the opposite of a thing before we know it completely. (402b5)
  • excessive pleasure =\= temperance == virtue

Doctors, it is true, would become cleverest if, in addition to learning the craft of medicine, they associated with the greatest possible number of the most diseased bodies right from childhood,62 had themselves experienced every illness, and were not, by nature, very healthy. After all, they do not treat a body with a body. If they did, we would not allow their bodies to be or become bad. But it is with a soul that a body is treated, and it is not possible for a soul to treat anything well if it is or has become bad itself. ... But a judge, my friend, does rule a soul with a soul. And it is not possible for a soul to be nurtured among bad souls from childhood, to have associated with them, and to have itself indulged in every sort of injus- tice, so as to be able to draw exact inferences from itself about the injustices of others, as in the case of diseases of the body. On the contrary, it itself must have no experience of, and be uncontaminated by, bad characters while it is young, if as a fine and good soul itself, it is going to make judg- ments about what is just in a healthy way. ... That is why a good judge must not be young, but old—a late learner of what sort of thing injustice is, who has become aware of it, not as something at home in his own soul, but as an alien thing present in other people’s souls. 408d10

  • virtue is the foundation upon which vice and injustice is built. One must fully understand virtue in order to understand vice for it is in the perverted seeking of virtue that vice is formed.
  • man is born with an innate sense of virtue within the body and soul. Some cannot grasp this virtue and have a naturally weak connection to their philosophical and spirited elements. In these cases no amount of musical or physical training will improve upon this weakness.
  • beliefs can be removed from someone through theft or compulsion (413a)

Book IV

  • To legislate about conventions such as hairstyles, clothing, chivalry, would never last (423a)
    • How are conventions different from what has been discussed before? What makes them so unenforcible?