We don't know who he's talking to, but Socrates, our super duper important narrator, begins by describing how he recently visited the port of Athens with a friend, Glaucon, to do some praying and to observe a religious festival that was being held there for the first time.
Socrates's feelings about the show? Generally, it was A-Okay.
As Socrates and Glaucon are leaving, another friend of theirs sees them and has his slave run over to get their attention.
The slave grabs Socrates's coat and says that his master, Polemarchus, insists that they wait up.
Socrates asks where in the world Polemarchus himself is, and the slave replies that he's coming soon, so they need to wait.
Socrates agrees to wait up, and sure enough, Polemarchus shows up with a bunch of other people: Adeimantus, Niceratus (the brother of Socrates's friend Glaucon), and some other unnamed folks.
Polemarchus says that it looks like Socrates is trying to hightail it out of there, which Socrates admits is true, but Polemarchus wants Socrates to stay and says that's he outnumbered. Polemarchus advises Socrates to "either prove stronger than these men or stay here!" (327c).
Socrates says that there might be another option: maybe he'll convince these dudes to let him leave.
Polemarchus wonders how Socrates will be able to be so convincing if no one even listens to him, anyway, and Glaucon chimes in saying it's impossible.
Adeimantus jumps in and asks whether Socrates is aware that later that night there's going to be a torch race on horseback (!).
Socrates is intrigued but doesn't totally understand how that would work (frankly, neither do we).
Polemarchus answers that they'll pass the torch to one another while on horseback and that there will be all sorts of other nifty events that night, too.
Polemarchus urges Socrates to stay with them for dinner, after which they'll all go in a big group with lots of young people to see the festivities.
Glaucon says it looks like they'll have to stay, and Socrates agrees.
So the gang heads over to Polemarchus's house, where there are even more people: Thrasymachus, Charmantides, Cleitophon, and Cephalus, Polemarchus's father.
Socrates remarks that Cephalus looks especially old. He says the old dude is probably seated on a stool with a wreath because he's just been performing some kind of sacrifice.
Everyone sits down next to Cephalus, who's totally happy to see Socrates.
Cephalus and Socrates Discuss Old Age
Cephalus says that Socrates should visit more often, since Cephalus is too old and weak to make a trip himself.
Cephalus observes that the older he gets, the less pleasure he gets from physical activities, and the more pleasure he gets from intellectual ones.
Cephalus tells Socrates to go hang out with the younger kids but asks him to make a point to come back and visit frequently.
Socrates replies that he enjoys taking with older people because they already know the way certain things in life go down and can offer good advice. Socrates says he's curious what Cephalus has to say about his age at the moment.
Cephalus says he's happy to fill Socrates in and explains that he and a bunch of other old people often hang out together and talk.
Cephalus explains that most of the other old people just complain and complain about all the things they can no longer do and enjoy: sex, drinking, festivals, etc. They gripe about how life isn't as good as it used to be and blame it all on old age.
But Cephalus is suspicious of how these old men reason, since he knows other old men who don't feel the same way they do. It obviously can't just be old age that makes these cranks so cranky.
For example, Cephalus describes something he overhead someone ask the poet and tragedian, Sophocles.
Brain bites! So maybe you haven't been keeping track of some of these other long Greek names, but Sophocles may ring some serious bells. He's a rock star writer of tragedies; you might know a couple of big bad ones called Oedipus Rex and Antigone. This guy is for real.
Okay, back to Cephalus's little story. Sophocles was recently asked whether he was still able to have sex with women now that he was old. He replied that he couldn't anymore, but he called sex a "frenzied and savage master" (329c). So good riddance, we guess.
Cephalus says that he found Sophocles's reply totally wise, since old age is indeed something that brings both peace and freedom.
Cephalus says it's true that desire can be a kind of master. Once you no longer have desire, you can finally relax.
Cephalus says that the real problem isn't someone's age but his or her character. Someone who is content in general will deal with old age just fine, whereas someone who isn't content in general will be unhappy when they're young and when they're old.
Socrates is interested in what Cephalus is saying and says that most people probably wouldn't agree with Cephalus.
Most people, says Socrates, would say it isn't Cephalus's good character but rather his wealth that makes old age less of an issue for him.
Cephalus agrees that most people probably wouldn't agree with him and admits that wealth obviously does make things easier. However, he says that it doesn't make things as easy as people think.
Cephalus says that even though someone who's content might still find old age hard if he or she were poor, someone who is not content would still find it hard even if he or she were rich.
Socrates than asks Cephalus whether he inherited his wealth, or whether he accumulated it himself.
Cephalus seems a bit confused by Socrates's two options, because he says he did both. He did inherit some family moolah, but it was much less than his family used to have, since his father spent a ton of it. All Cephalus did was make up some—but not all—of the money his father lost.
Socrates explains that he asked the question because he notices that Cephalus isn't especially interested in money. Socrates suggests that people who inherit money tend to be like this. However, people who make their own money are extremely interested in it, just as poets love their own poems and fathers love their own children.
Of course, says Socrates, those who love wealth love it not only because it's their own but also because of what it allows them to do. Socrates says people who are obsessed with wealth are super annoying to be with because all they want to talk about is how much they love wealth.
Cephalus agrees and Socrates then asks what Cephalus thinks is the best thing about being wealthy.
Cephalus says that he doubts his reasons would convince many people.
Cephalus says that when people get old, they tend to suddenly get nervous about all kinds of things they weren't worried about when they were young—like, say, whether they'll be punished in the afterlife. Cephalus isn't sure if this happens because old age makes people a little nutty or if it happens because people do actually know something about death as they approach it. Either way, it's a fact.
This means that an old man who's been up to all sorts of bad things in his youth will be freaking out as death approaches, but an old man who has done good stuff in his life will be totally relaxed and happy. Cephalus brings out the heavy artillery and quotes a line from the poetry of Pindar for extra proof.
Brain bite! Pindar? Pindar was an A-list Greek poet. He wrote tons of odes and inspired generations of poets after him.
So, Cephalus concludes that the nice thing about having wealth is that it allows you to not only not worry about cheating or lying (he doesn't go into a whole lot of specifics here, so we kind of have to take his word), but also you won't be worried about dying without having paid off all your debts.
That's true, says Socrates, but since Cephalus has brought up the issue of justice, Socrates wants to think a little more about that. He's not convinced that justice is as simple as just being able to give back what someone has taken. Socrates actually imagines that sometimes doing that is just but at another time it might be unjust.
For example, if someone takes a weapon away from a friend and then later, randomly, this same friend loses his mind, when he asks for his weapon back, it would be just for the friend who took the weapon not to give that weapon back. On top of that, it would even be just not to be completely honest with this crazy, weapon-wanting friend.
So, obviously we can't just define justice as telling the truth and giving back things taken.
Polemarchus and Socrates Discuss Justice
Polemarchus interrupts here and disagrees with Socrates, insisting that the above would be a good definition of justice according to someone called Simonides. Well, if you're going to bring up Simonides...
Cephalus bows out of the debate to go conduct a sacrifice. He makes a joke that it's fitting that his son Polemarchus should inherit this argument. Haha. What a joker.
Socrates then asks Polemarchus to explain exactly what Simonides said about justice.
Polemarchus replies that Simonides simply said that justice is when you give people what you owe them.
Socrates says that he doesn't want to disbelieve Simonides, since he's smart dude (apparently), but he honestly just doesn't understand. Simonides wouldn't agree that a crazy man should be given back his weapon, but it is still his weapon, so technically, it's owed to him. Since Polemarchus says that Simonides would agree with that, Socrates says he's just totally confused.
Polemarchus suggests that Simonides meant that friends owe friends good things, not bad things.
Aha. Socrates says he understands now: Simonides wouldn't want a friend to return gold if it turned out to be a bad transaction.
What about enemies? asks Socrates. Do you have to give things back to enemies that you owe them?
Yep, say Polemarchus. And enemies owe their enemies harm. Um, what?
But then Simonides made a riddle, complains Socrates, when he said that it is just to give everyone what is fitting and called this "what is owed."
Socrates asks what Simonides would say if someone were to ask him what medicine "owes."
Easy, says Polemarchus: medicine owes drugs, food, and drinks to bodies. (It does?)
Socrates then asks the same question about cooking, and Polemarchus replies that it owes seasonings to meat. (Is this philosophy?)
Finally, Socrates asks what justice "owes," and Polemarchus answers that justice is doing good to friends and harm to enemies.
Socrates then asks who is most able to do good to the sick and bad to enemies. Polemarchus replies: doctors.
Socrates asks now about who has power over the sea and those sailing. The answer: pilots. So, asks Socrates, what about the just man? In what way is he most able to help his friends and harm his enemies? And Polemarchus thinks this would be in war: fighting enemies and making alliances with friends.
Socrates replies that when someone is healthy, a doctor is useless, and when someone is not sailing, a pilot is useless, too. Polemachus agrees.
So then Socrates asks if just men are useless unless there is a war. Polemarchus doesn't really think so.
Socrates then pulls out a bunch of examples of other activities that are useful in times of peace, like farming to get food and shoemaking to have shoes. He then asks what justice provides during peacetime, and Polemarchus suggests that it is necessary to make contracts, which Socrates understands to mean communal partnerships, not just financial agreements.
Socrates then wonders if a just man is useful in playing a game of draughts (kind of like an ancient version of checkers), or if you'd rather have a super awesome draughts player. Surprise, surprise: Polemarchus would rather have the super awesome player.
Socrates asks a similar question about building a house, and Polemarchus once again says that he would rather have a professional house-builder as a partner than a "just man."
So, Socrates says he just doesn't get what kind of a project a just man would be useful for. Polemarchus suggests that he'd be useful in issues of money.
But Socrates insists that even so, if you were buying a horse, for example, you'd still want someone who knows about horses, and the same would go for buying a ship. Polemarchus agrees with all that, and so Socrates again asks what kind of monetary transaction needs the just man.
Polemarchus replies that a just man would be useful when you need to keep your money safe. So Socrates concludes that therefore, just men are only useful when things are not being used: money, weapons, precious instruments, etc.
Socrates points out that according to this account, justice doesn't seem to be a very important concept. Socrates suggests they try another tactic.
Socrates asks if a good boxer is someone who can both throw a good punch and defend himself against one. Polemarchus says: yeah, totally.
So then, says Socrates, if you're good at preventing illness, you should be good at creating it, too. If you are guarding a good army, you should be able to steal another army's plans. But that means that (by this logic), anyone who is good at guarding something must be good at stealing, too. Polemarchus is all like: "I see how this debate is going."
Socrates is like, hey, if we follow this logic, it looks like the just man is a kind of thief. That's totally a problem, right? It turns out that even Homer praised someone who cheats and steals as a just man.
Brain bite! Homer. Yes, that Homer, the epic poet who wrote the Iliad and the Odyssey. Plato, through Socrates, loves talking about (and criticizing), so head on over to our Homer guides if you start getting lost.
Socrates says that Homer and Simonides both dish up definitions of justice in which you steal to help out your friends.
Poor Polemarchus is all confused (don't worry if you are, too) and just repeats his early definition of justice as helping friends and harming enemies.
But now Socrates is all over the idea of friendship and what it means. Are friends actually good people, or are they just people we like to hang out with who seem to be good?
Polemarchus isn't sure, but he imagines that people tend to be friends with the kind of people they think are good.
Socrates says that people are often wrong in what they think, so what often happens is that bad friends will be treated well and truly good people will be harmed. Polemarchus isn't convinced by this line of thinking.
Socrates says that because most people make mistakes and are wrong about their friends and enemies, justice actually means being harmful to friends (because they aren't actually good) and being good to enemies (because they aren't actually bad).
Polemarchus is just more and more confused and suggests that they ought to redefine friendship. Friends shouldn't just be defined as people who seem to be good, but rather people who both seem and are good; the inverse goes for enemies.
All right, so Socrates has a new definition of justice: doing good to friends who are good and harming enemies who are bad. Polemarchus is sold.
Socrates then asks whether people should always harm bad people. Polemarchus says yes. Then Socrates offers some examples of how harming both horses and dogs makes them worse, not better, and then claims that humans who are harmed actually become less virtuous and less just. Polemarchus has to agree.
Socrates then goes on to question how things improve. He claims that in both music and horsemanship, someone doesn't become worse at those things by constantly doing them. So he then wonders if a just man can use justice to make someone unjust, which Polemarchus agrees doesn't make very much sense. Did you follow that logic? Harming dogs and horses makes them worse; so harming your enemies probably also makes them worse and therefore less just. But being just can't make others become less just, so it can't be just to harm your enemies.
Socrates points out that instead it's a question of opposites: heat doesn't cool, wet doesn't dry, and so justice doesn't harm—only its opposite does. This conclusion completely contradicts Polemarchus's original definition that justice is doing good to good people and bad to bad people, because "it is never just to harm anyone" (335e).
Polemarchus is totally convinced and says he's 100% on Socrates's side. Socrates suspects that this nutty idea that justice can include harming your enemies must have been invented by someone very arrogant.
But Socrates isn't done. He wants to actually find a definition of justice.
Fasten your seat belts and sit back, folks, because it's going to be a long ride.
Thrasymachus and Socrates Discuss Justice
At this point, Thrasymachus jumps in. Thrasymachus, we're told, has been trying to interrupt the debate this whole time, and now he just can't control himself. In fact, he's so worked up about how the conversation has been going that he jumps up violently, scaring Socrates and Polemarchus.
Thrasymachus accuses Socrates of spouting nonsense and presses him to actually provide his own answer instead of just questioning other people's answers all the time. And Thrasymachus doesn't want any of Socrates's vagueness; he wants clear and definite specifics.
Socrates was kind of freaked out by this violent interruption and says he almost became speechless. (Ha ha. Good one, Socrates. When has that ever happened?) However, he finds some confidence and answers that if he and Polemarchus made a mistake, it was completely unintentional; obviously, they both really want to discover what justice means. They're motivated, just incompetent, and they deserve the pity smart men like Thrasymachus.
We see what you're up to, Socrates.
Thrasymachus is not impressed. He laughs and accuses Socrates of being ironic (as usual) instead of actually answering the question.
Socrates defends himself by saying that Thrasymachus made the questions impossible to answer by limiting the way he could answer. A person can only answer in the way they know.
Thrasymachus imagines Socrates will just do what he wants and answer in his usual way. He then challenges Socrates: what will Socrates do if he, Thrasymachus, can define justice in a better way than the big S himself?
Socrates says he'll happily learn from Thrasymachus, but Thrasymachus wants money, which Socrates says he doesn't have.
Glaucon steps in and says Socrates does have some money, and they should go ahead with the challenge. Everyone else present will support Socrates, which Thrasymachus thinks is typical of Socrates's usual tricks.
Socrates asks Thrasymachus why he would expect him to be able to answer, since he has never claimed to be able to know anything; it's Thrasymachus who claims to have an answer.
A brain bite interruption! Socrates is famous for claiming he doesn't know anything—it's kind of his thing. Check out our "Character Analysis" section for more.
Thrasmymachus continues to act as if he didn't want to answer, though Socrates suspects that he really wants to show off how good his answer is. Thrasymachus then accuses Socrates of learning from other people without teaching anything in return.
Socrates agrees that he learns from others but objects to the idea that he gives nothing in return. He admits he has no money, but he will repay wisdom with high praise.
Thrasymachus defines the just as simply the advantage of the stronger. He says Socrates ought to praise him but knows he won't.
Socrates says he first needs to understand and asks if Thrasymachus is saying that a wrestler, because he is stronger than the present company, would therefore be more just than the present company.
Thrasymachus is not impressed and says Socrates is twisting his meaning, showing it in the worst light possible. He was only talking about political strength, he says. For all three types of ruling systems—democracy, tyranny, and aristocracy—there are corresponding laws that make whatever is good for the rulers "just" and whatever isn't good for the rulers "unjust."
Socrates is intrigued, though he also points out that Thrasymachus has answered in a way he forbade Socrates from doing earlier.
Socrates says he's generally down with the idea of connecting justice and advantage but isn't sure if it's the advantage of the stronger that is important.
Socrates presents Thrasymachus with one of his (in)famous examples (you should be getting pretty used to them by now): the example is strong rulers. Thrasymachus agrees that it is just to obey rulers, but he also agrees that rulers can sometimes make mistakes. Socrates, therefore, shows that if a ruler mistakenly forced one of his subjects to do something unjust, thinking it was just and to his own advantage, it would mean that, according to Thrasymachus's definition, something unjust would be just simply because a ruler commanded it.
Polemarchus jumps in here and enthusiastically agrees with Socrates's reasoning.
Cleitophon isn't so convinced. Cleitophon insists that Thrasymachus didn't say justice was what was to the advantage of the stronger—the rulers, in this example—but what seemed to be. So, according to Cleitophon, Thrasymachus is still correct.
Socrates then runs this interpretation by Thrasymachus, who immediately says that this is not at all what he meant. Instead, he insists that when he was describing someone as "stronger," he was speaking about this person in general and obviously not in the single, few moments when he or she is making a mistake.
Socrates says he didn't realize that that's what Thrasymachus was saying, which really ticks Thrasymachus off.
Thrasymachus accuses Socrates of being someone who makes needless and self-serving accusations, and he again says that a ruler, or a doctor, is overall a strong person, even if you wouldn't necessarily describe him that way in those instances when he makes a mistake.
Socrates then asks Thrasymachus if he thinks that he, Socrates, makes these self-serving accusations because he is trying to ruin Thrasymachus's ability to argue.
Thrasymachus says he doesn't know, but he doesn't care, and he isn't going to let Socrates derail him.
Socrates suggests that they get back to the issue and asks Thrasymachus to clarify this whole situation. He asks whether Thrasymachus is talking about really precise and exact definitions or just the ones regular people throw around.
Thrasmymachus says he's totally precise and challenges Socrates to find a problem with his reasoning. We think he should probably realize that's a bad idea by now, but hey, that's just us. If you want to take on the big guy, be our guest.
Socrates takes up his usual strategy by giving examples in response. He asks whether Thrasymachus considers a real doctor to be one who makes money or cares for the sick, to which Thrasymachus unsurprisingly says one who cares for the sick.
Next Socrates asks about pilots, and he and Thrasymachus both conclude that a pilot would be considered a ruler of sailors, and not a sailor himself, because even though he sails, he's a pilot due to his role as a leader.
Socrates asks if all subjects or practices aim only for their own perfection, making them completely self-sufficient, or if all subjects are also involved in and need aspects of other subjects to find their greatest advantage.
Thrasymachus suggests that a subject should confine itself to its own concerns, so Socrates clarifies that medicine, in that case, is concerned with the body, and not with medicine itself, just as horsemanship would concern itself with horses and not with horses and not with horsemanship itself.
Socrates demonstrates that according to this break-down, a subject doesn't actually look to its own advantage (as Thrasymachus has previously claimed) but rather to the advantage of the things it is in charge of: a good doctor doesn't try to do the best thing for himself but for his patients, and the same is true of a pilot and his sailors.
So Socrates shows that Thrasymachus's entire definition of a "ruler" is flawed, because a true ruler isn't worried about himself but about the things under his or its control.
Surprise, surprise (not), Thrasymachus isn't too happy about the way the argument is going. So he starts insulting Socrates. Basically, he's like, "Socrates, you're a Grade A, gold-medal moron." Does Socrates really think that, say, a shepherd is concerned only for the welfare of his sheep and not with the food and clothing the sheep will provide him? On top of that (says Thrasymachus), anyone can see that people who are truly just are actually much worse off than those who are unjust. The real answer, Thrasymachus claims, is that justice is something that is to the advantage of other people, while being unjust is something that is to your own advantage.
After announcing this, Thrasymachus almost tries to leave in a huff, but no one will let him. They want to think more about what he has just said. And anyway, Socrates reminds him that the topic at hand is of crucial importance for everyday life.
Socrates goes on to say that by staying, Thrasymachus is looking out for his friends and making sure they have adequate knowledge of how the world works. Good one, Socrates.
Besides, Socrates isn't convinced by Thrasymachus's reasoning; he doesn't believe that injustice is more profitable than justice, and he wants Thrasymachus to prove his point.
Thrasymachus says that if Socrates wasn't persuaded already, he can't say anything more to convince him.
Socrates ignores this and says that it's clear from Thrasymachus's description of a shepherd (as someone who takes care of his sheep for primarily selfish reasons) that his definition of ruling has changed since his previous definition of ruling as a doctor as someone who cares for his patients
Socrates asks if rulers of cities rule willingly, and Thrasymachus says he is sure they do.
Socrates says that other kinds of rulers are given a salary, or compensation, which suggests that they consider ruling to be for the benefit of those they rule and not just for their own benefit. Socrates returns to the topic of disciplines, specifically talking about how each discipline is differentiated on the basis of the thing it deals with (pilots: sailing, doctors: medicine).
Socrates points out that the only thing various disciplines have in common is that each incorporates the practice of collecting wages to help people make a living: a doctor isn't any less of a doctor because he makes money doing it. Socrates asks whether a doctor would gain any obvious benefit to himself from practicing medicine if he didn't charge a fee, and Thrasymachus admits that he wouldn't.
Therefore, Socrates concludes that ruling does not bring its own advantage, but an incentive needs to be added: it could be money, or honor, or the fear of a penalty if the person doesn't rule.
Glaucon joins in and says he doesn't understand the last bit about a penalty.
Socrates explains that truly good men, the kind you want to be in charge, aren't solely interested in either money or honor. Therefore, they are motivated to rule because they are afraid that if they don't, someone bad might rule instead. Socrates guesses that in a city of truly good men, people would do their very best to avoid ruling. They wouldn't try to rule, as so many people do now.
Socrates says that he wants to go back and examine Thrasymachus's claim that the unjust man is stronger than the just one. He asks Glaucon what he thinks, and Glaucon says he believes that the life of the just man ought to be the stronger one. Socrates then suggests they try and convince Thrasymachus—not by having everyone deliver and compare long speeches, but by means of a dialogue.
Socrates turns to Thrasymachus and asks him what kind of moral differentiation is possible if Thrasymachus believes that justice is weak and injustice is strong.
Thrasymachus replies that he wouldn't use the language of "virtue" and "vice" but instead would call justice "very high-minded innocence" and injustice "good counsel" (348c-d). But he does imply that injustice would belong in the category of virtue.
This last implication bothers Socrates quite a bit (we don't blame him). He begins to ask Thrasymachus about the behavior of a hypothetical "just man." Would this man ever try to get the better of another person? (Answer: no.)
Socrates asks if this just man would think he deserved to at least get the better of an unjust man. Would that to be just or not?
Thrasymachus answers that the just man would think that is just, but wouldn't ever be able to get what he deserves (because he'd too high-and-mighty, given that he's a just man). Thrasymachus and Socrates both agree that the unjust man thinks he deserves to get the better of everyone.
Socrates sums up the position as it stands: just people get the better of only unlike people (the unjust), whereas unjust people get the better of people both like and unlike (both just and unjust).
Socrates asks about someone who is musical versus someone unmusical and someone knowledgeable about medicine versus not knowledgeable about medicine. Thrasymachus says that someone musical or knowledgeable about music is prudent, while someone unmusical or not knowledgeable about medicine is thoughtless.
Socrates asks whether a musical man thinks he deserves to do better than another musical man or a man who isn't musical, and Thrasymachus says that a musical man will want to do better than an unmusical man, and says the same of a medical man.
Socrates makes the questions more general and asks whether someone who is both good and wise will want to get the better of other good and wise men, or just worse ones. Thrasymachus says only worse ones, while the ignorant and bad man will think he should get the better of both wise and ignorant men.
However, Socrates points out that according to this model, the just man, who gets the better only of that which is dissimilar to himself (and not of that which is similar to himself), is therefore like the good and virtuous man, not the ignorant man Thrasymachus was trying to compare him to.
Socrates notices that poor Thrasymachus is totally blushing.
Socrates continues on, anyway, and asks whether injustice is still mighty, even if it isn't good and just.
Thrasymachus says he remembers that part, but he's still not convinced by Socrates's conclusions. He says that Socrates won't even let him speak, since he'll just accuse Thrasymachus of making a scene. So Thrasymachus says he'll let Socrates just keep on questioning him—but he's just going to nod yes without really listening. Okey dokey, says Socrates.
Socrates wants to make sure they are very thorough about this whole justice thing, so he asks whether Thrasymachus thinks a city that tries to enslave other cities is just or unjust. Thrasymachus says it's definitely unjust and that, for this reason, it will be very strong.
Socrates is delighted that Thrasymachus is answering his questions so well, and Thrasymachus quips that he's just doing it to be nice to Socrates.
Socrates, grateful, goes on to ask whether any community that as a whole acts unjustly could survive if its various members acted unjustly to one another. Thrasymachus says probably not, and he and Socrates agree that the reason for this is that injustice causes factions and arguments that prevent unity.
Socrates suggests that this could be true even within a single person. If injustice is a part of this person, it will make him divided against his own self—which would prevent him from being very powerful, right?
Plus, Socrates adds, the gods like people who are sure of themselves and able to make good choices. So if the unjust man isn't able to be sure of himself, being all divided and such, the gods won't like him. Again: doesn't make him sound too powerful, does it?
Socrates sums up where they stand by saying that clearly the just man is much better able to accomplish things. What remains to be seen, he says, is whether justice allows someone to live better.
Socrates wants to understand this concept of "better" and asks Thrasymachus whether what something does is determined by 1) what it's capable of doing or 2) what it does best. (So, you can only hear with your ears and see with your eyes, but take, say, a pruning-knife: although you can do things other than prune with it, we still think of it as a pruning knife because it prunes best.)
Socrates and Thrasymachus agree that things that do a certain thing best also have their own virtue (so seeing might be the virtue of eyes, and hearing might be the virtue of ears). Without its virtue, an object wouldn't do its job well.
So now Socrates wants to talk about souls and what they do best: managing, organizing, living, that kind of thing. Socrates and Thrasymachus also agree that the soul will not do any of these things well if it lacks virtue, and this virtue is—you guessed it—justice.
Virtue leads to being both blessed and happy, and so, ta-da, injustice can never be more profitable than justice.
Socrates thanks Thrasymachus for pointing out this topic of conversation. He compares himself to a glutton at a banquet who grabs whatever he sees and just can't stop once he's hooked. Philosophy: once you pop, you just can't stop.