The Noble Lie
Plato's Republic, Book 3

Table of Contents

Picture of <b>Brennan McDavid</b><br><small>Assistant Professor of Philosophy, Chapman University</small>
Brennan McDavid
Assistant Professor of Philosophy, Chapman University

Warm-Up: The Power of Modern Myths

How would you summarize the American Dream? Many believe that the American business and social landscape is one in which glamorous prosperity and upward social mobility are possible for anyone willing to put in the hard work. But is this really true? Investigating the question in earnest means running the risk of losing faith in the American Dream and, in turn, the high-productivity mindset that keeps America’s GDP high and churns the waters of innovation, industry disruption, and technological booms.

Political rulers often harness the power of myths like the American Dream for shaping the attitudes of subjects and constituents. Whether by prescribing to the notion of a “divine right of kings” or else to the idea that “every vote counts,” modern political myths have power insofar as they are believed, and so it is always in the interest of ruling entities to support belief in the myths that sustain the political status quo.

In today’s reading, we will examine the first explicit appeal to such myth-making in political philosophy. Plato’s Republic features a “Noble Lie” that is intended to control the beliefs of citizens in his ideal city.

Introduction

Plato (427 – 348 BC) was an Athenian philosopher who was greatly influenced by the life and death of Socrates. He founded a school called The Academy, from which modern academia derives its name. Plato’s philosophical works are not written in his own voice, but instead in the form of dialogues that often figure Socrates in conversation with one or more interlocutors. It is commonly quipped, following Alfred North Whitehead, that all of western philosophy is “a series of footnotes to Plato.”


The Republic is widely regarded as Plato’s greatest work. It features his ideal political theory, moral psychology, and the crowning achievement of his metaphysics: the Theory of the Forms. The topic of this reading is one of the many controversial elements of his political theory. For cities to flourish, he argues, citizens must believe in carefully crafted myths that will control their conceptions of who they are and how they should relate to one another. Plato calls such myths “Noble Lies,” a name that indicates the nature of the controversy: Plato is explicitly recommending the cultivation of false beliefs in citizens. The presentation of the Noble Lie that he has in mind for the ideal city of the Republic occurs at the end of Book 3. For those interested in reading Book 3 in its entirety, the translation used in this reading can be found here.

Key Concepts

Collective Myth – A story that is embraced by a community as part of their group identity and that they rely upon for decisions or motivation

Nature – The original and unchangeable condition that a person or entity possesses upon birth

Nurture – The education, training, and other environmental processes that influence the direction of development for a person or entity 

Political Propaganda – The dissemination, by a state or other political actor, of information with the intention of controlling the beliefs and influencing the actions of the recipients

Truth and Lies in the Platonic Society

The (in)famous “Noble Lie” is introduced by Socrates at the end of Book 3 of the Republic. Before reaching that point, though, Plato provides a more abstract introduction to the concept and utility of falsehood. In conversation with Adeimantus, Socrates characterizes lies as a potential “medicine,” suggestive of the idea that they can be good.

Book 3, 389b-c
We must surely prize truth most highly. For if we were right in what we were just saying and falsehood is useless to gods, but to men useful as a remedy or form of medicine, it is obvious that such a thing must be granted to physicians and laymen should have nothing to do with it.

Obviously, he replied.

The rulers then of the city may, if anybody, rightly lie to and about enemies or citizens for the benefit of the state; no others may have anything to do with it, but for a layman to lie to rulers we shall affirm to be as great a sin, even greater than it is for a patient not to tell physician or an athlete his trainer the truth about his bodily condition, or for a man to deceive the captain about the ship and the sailors as to the real condition of himself or a fellow-sailor, and how they fare.

Likening lies to medicine and the rulers of a given society to doctors, Socrates argues that lies can be useful and even curative if they are prescribed in the right dosage and with the right aims. If the ruler can benefit his society by doing so, he is justified in lying to enemies and even to the citizens themselves. But none of the citizens can ever be justified in lying to the ruler.

Video

Socrates’ City

When Plato talks about rulers potentially using lies for the benefit of society, he has a particular society in mind. It is one in which citizens are divided into three classes. The largest class by far is made up of “producers,” those who make and trade the material goods consumed by the city. The remaining citizens are collectively called “guardians,” but they are divided in two: the “rulers” who write legislation and generally manage the city, and “auxiliaries” who help the rulers by enforcing the law. Learn more about how Plato motivates the division into these three classes here:

The Propaganda Machine

Near the end of Book 3, Socrates completes his introduction of the three classes in the city by explaining that the rulers are a special subset of the city’s guardians. They are the citizens who demonstrate unwavering loyalty to its political constitution. When Glaucon agrees that this arrangement is ideal, Socrates moves to consider how the city will ensure that citizens stay within their respective classes.

Book 3, 414b-c

How then may we devise one of those useful falsehoods of which we lately spoke—just one royal lie which may deceive the rulers, if that be possible, and at any rate the rest of the city?

What sort of lie? he said.

What is called a “royal lie” here is often translated as “noble lie” or “noble falsehood.” Socrates’ proposal is that the citizens can be kept within their classes by controlling their beliefs with a lie.

Thought Experiment

What Sustains Collective Myths?

Socrates reveals that he hopes everyone living in the ideal city will believe in the lie, but that he is less confident of his and Glaucon’s ability to craft a falsehood that will deceive the rulers. The “rulers” and “the rest of the city” are differentiated, then, for their susceptibility to belief manipulation. The rulers are more resistant to falsehood. But Socrates aims for total influence, if he can have it, and in this sense we can understand the “noble lie” as a collective myth that everyone in the society of the ideal city will believe in.

Reflect on the driving myths of your own social environments. Do those myths depend on the faith of every member of the group? Or can they be sustained by only a segment of the group’s population? If one segment’s confidence matters more, why is that the case?

The Earth Mother Myth

Glaucon asks “what sort of lie” Socrates wants them to craft.  Socrates’ answer is surprising: Instead of specifying the “sort” of lie by referencing a genre of stories or a set of themes, he articulates the very myth that he thinks is sufficient for securing compliance among the citizens.

Book 3, 414c–e

What sort of lie? he said.

Nothing new, I replied; only an old Phoenician tale of what has often occurred before now in other places, as the poets say, and have made the world believe, though not in our time, and I do not know whether such an event could ever happen again, or could now even be made probable, if it did.

How your words seem to hesitate on your lips!

When you hear it, you will not wonder at my hesitation, I replied.

Speak, he said, and don’t be afraid.

Well then, I will speak, although I really know not how to look you in the face, or in what words to utter the audacious fiction, which I propose to communicate gradually, first to the rulers, then to the soldiers, and lastly to the people. They are to be told that their youth was a dream, and the education and training which they received from us, an appearance only; in reality during all that time they were being formed and fed in the womb of the earth, where they themselves and their weapons and tools were manufactured; when they were completed, the earth, their mother, sent them up; and so, their country being their mother and also their nurse, they are bound to advise for her good, and to defend her against attacks, and her citizens they are to regard as children of the earth and their own brothers.

You had good reason, he said, to be ashamed of the lie which you were going to tell.

Socrates draws on ancient myths of autochthony—literally, “born of the earth”—which depict the earth as a literal mother who gives birth to human beings in particular places, giving those native populations a familial bond to their land. Most importantly, by representing whole populations as being “earth-born” in this way, autochthony myths facilitate belief in a natural brotherhood between individuals.

Objection

Lies Have No Place in the Ideal City

Plato voices objections to the idea of a “noble lie” when he has Glaucon assert that Socrates has “good reason to be ashamed” for proposing this political tool. But does Glaucon object to the use of falsehood itself or else to the particular content of the autochthony myth? Why are lies objectionable? Is it because they are untrue or because we wish for different content in our falsehoods?

Much of the criticism of Socrates’ recommendation has focused on the purported “nobility” of the lie. Even if we may find some justification in persuading someone of a falsehood, can we rightly say the lie is noble? Further, there is special tension in feeding a lie to the rulers of Plato’s ideal city. They are not ordinary legislators, but philosophers (literally “lovers of wisdom”). Convincing them of a lie is in contradiction to who they are. 

Even if there is an end that justifies lying as a means, it is difficult to see noble lies as anything other than political propaganda, which can certainly be put to nefarious purposes. Adolf Hitler wrote in Mein Kampf that people are more likely to trust in a “Big Lie” than a small one because it is difficult to conceive of the audacity required for telling the big one. How should we assess Socrates’ strategy for achieving social compliance then?

The Myth of Metals

Socrates concedes to Glaucon that there is shame in his proposal, but then reveals that his Noble Lie is only half-told so far.

 Book 3, 415a – d

True, I replied, but there is more coming; I have only told you half. Citizens, we shall say to them in our tale, you are brothers, yet God has framed you differently. Some of you have the power of command, and in the composition of these he has mingled gold, wherefore also they have the greatest honour; others he has made of silver, to be auxiliaries; others again who are to be husbandmen and craftsmen he has composed of brass and iron; and the species will generally be preserved in the children. But as all are of the same original stock, a golden parent will sometimes have a silver son, or a silver parent a golden son. And God proclaims as a first principle to the rulers, and above all else, that there is nothing which they should so anxiously guard, or of which they are to be such good guardians, as of the purity of the race. They should observe what elements mingle in their offspring; for if the son of a golden or silver parent has an admixture of brass and iron, then nature orders a transposition of ranks, and the eye of the ruler must not be pitiful towards the child because he has to descend in the scale and become a husbandman or craftsman, just as there may be sons of craftsmen who having an admixture of gold or silver in them are raised to honour, and become guardians or auxiliaries. For an oracle says that when a man of brass or iron guards the State, it will be destroyed. Such is the tale; is there any possibility of making our citizens believe in it?

Not in the present generation, he replied; there is no way of accomplishing this; but their sons may be made to believe in the tale, and their sons’ sons, and posterity after them. 

I see the difficulty, I replied; yet the fostering of such a belief will make them care more for the city and for one another. Enough, however, of the fiction, which may now fly abroad upon the wings of rumour, while we arm our earth-born heroes, and lead them forth under the command of their rulers.

This dimension of the Noble Lie is called the “Myth of Metals” because it identifies general types of people with precious (gold and silver) and industrial (iron and bronze) metals. The proposal of the myth is that each individual person belongs to one of the four general types because of their essence. These essences determine what role is proper for each individual in the city: the golden types are rulers; the silver types are auxiliaries who enforce law as written by the rulers; the iron and bronze types are farmers and craftsmen.

Connection

The Nature vs. Nurture Debate

One function of the Noble Lie is to convince the citizens of the ideal city that their position in the hierarchy of society is natural. Earth, as their mother, fitted them with the skills and tools of their occupation. And, likewise, god distinguished each class (the craftsmen and farmers, the soldiers, and the rulers) by putting different metals in their souls. By identifying earth and god as explanatory in these ways, the myth conveys the idea that facts about each person’s nature are responsible for their life station. 

The alternative belief that the citizens might hold would be that nurture is the cause of differences between individuals. That is, they might believe that the rulers have power because they were chosen by human beings to receive a special education and the auxiliaries are strong and courageous because they were selected by human beings into military training. If the citizens of the ideal city believe that nurture explains these differences, then they might be inclined to think that the social hierarchy can be revised and that they could occupy a different position in society. The Noble Lie enshrines nature as the author of the social arrangement and encourages compliance with the status quo. 

The larger argument of the Republic places a great deal of emphasis on education and getting all the details of upbringing right, so we cannot conclude that Plato believed that nature is a more significant cause of human outcomes than nurture. What is the state of this debate today? Do nature and nurture figure in modern collective myths?

Summary

The content of Plato’s Noble Lie concerns both the nature and the nurture of citizens in his ideal city. It tells a story of brotherhood among all the citizens, bonding them together in familial love so that they will be motivated to care for and be cooperative with one another. And it also tells a story of personal responsibility in playing the role that one is cut out for in order to contribute maximally to the good of the whole. In Plato’s vision, these collective myths motivate individuals to harmonize with one another and, in turn, to achieve the greatest harmony possible inside themselves too.

Connection

Who Will Guard the Guardians?

Juvenal, the Roman poet of the 1st and 2nd centuries AD, crystalized a timeless question of political theory when he asked “Who will guard the guardians?”

The question can be discerned in Plato’s proposal that even the rulers should be deceived by the Noble Lie. As a political tool, it is useful even when deployed on the rulers and perhaps even most useful when deployed as such. On this interpretation of Plato’s motivation, the Noble Lie is not a tool that the rulers wield for controlling the other citizens, but it is a check on the ambitions of the rulers themselves. 

The remaining puzzle is to reconcile this picture of the rulers deluded by the same collective myths as the other citizens with the claim we visited at the beginning of this discussion: if the rulers alone are capable of administering lies like a medicine, then who in the city remains to administer the lies to the rulers? What does Plato propose as a mechanism for ensuring that the right beliefs are circulating within the ideal city?

Want to Learn More?

For a fuller account of why Socrates wants the rulers and everyone else in the ideal city to do the particular jobs that they are assigned, you can read the whole of Plato’s Republic.  In particular, there is a more detailed description of the roles of nature and nurture in the development of rulers in Book 6 and Book 7. There we learn that the rulers possess an inborn love of learning and must undergo a rigorous education to acquire the knowledge requisite for ruling well, which is revealed to be philosophical knowledge. The purpose of the Noble Lie is to convince those rulers to stick with their education and their work of ruling. The Stanford Encyclopedia of Philosophy also offers helpful articles for learning more about Plato’s Myths and about Ethics and Politics in the Republic.

Acknowledgements

Citations of Plato’s text in this work are adapted from the Republic of Cleveland State University’s Michael Schwartz Library Pressbooks Collection. This work is in the public domain. All images were created using Midjourney.

Citation

McDavid, Brennan. 2025. “The Noble Lie: Plato’s Republic, Book 3.”  The Philosophy Teaching Library. Edited by Robert Weston Siscoe, <https://philolibrary.crc.nd.edu/article/the-noble-lie/>.

Key Concept

Monarchy – A monarchy is a state where political deliberation is performed by one person (generally a king or queen).

Key Concept

Phalaris (c. 570-549 BCE) was, by most accounts, the very opposite of Cyrus, and he was used as an example of tyrannical cruelty in antiquity. He was tyrant of Acragas (now Agrigento) in Sicily. Diodorus Siculus records an infamous account of Phalaris’s torturing his enemies in a bronze bull placed over a roaring fire.

Key Concept

Cyrus the Great (d. 530 BCE) was the first emperor of the Persian Empire and a commonly used exemplar of the “enlightened monarch” in antiquity. He was renowned for his tolerance and care for his subjects. Xenophon, a student of Socrates, wrote a partly fictionalized biography of Cyrus called The Education of Cyrus (Cyropaedia). Peter Drucker, an influential 20th-century management theorist, called the Cyropaedia the best book on leadership.

Key Concept

Republic (res publica) – Cicero’s short definition of res publica is res populi (the ‘people’s thing’). Later in the Republic, Cicero famously defines a republic (1.39) as an assemblage of people associated with each other by consensus on justice (ius) and mutual benefit (utilitas).

Key Concept

Scipio Aemilianus Africanus was a hero among many Romans, but his reputation today is far less straightforward. Scipio Aemilianus led a Roman military campaign resulting in the utter destruction of the city of Carthage in 146 BCE. The Carthaginians were a prosperous Phoenician people in North Africa and rivals to Roman power. It has been argued that this act of ‘national extermination’ meets the modern definition of genocide. How should this knowledge impact how we view Scipio’s political philosophy expressed here?

Key Concept

This famous phrase, known by the abbreviation SPQR (senatus populusque Romanus), served as something like the official title of the Roman state (compare ‘USA’, ‘USSR’, ‘UK’), and encapsulated the ideal of a res publica (common property in public hands shared between the people and a council of elders).

Key Concept

Contemplation: The activity of human beings’ rationality. Contemplation is more than just thinking; it’s thinking excellently about ultimate truths. Contemplation is the ultimate activity associated with human flourishing.

Key Concept

Eudaimonia: Often translated as ‘happiness’ (in this text) or ‘flourishing’, eudaimonia is the activity of living the best possible life for a human being. Eudaimonia is more than just feeling happy or contented – it’s the idea that there is a best way to live for human beings.

Key Concept

Virtue: Virtues are cultivated tendencies to perform our function excellently, which allow us to reliably do the right thing, to the right extent, for the right reasons, given the demands of a specific circumstance. There are three components of virtues: virtues involve (a) skillful activity – they’re excellences after all!, (b) proper motivation, and (c) appropriate judgment – they often lead to judgments about what is the right thing to do, which requires careful attention to the circumstances.

Key Concept

Pleasure: The enjoyable feeling that accompanies some activities. Some philosophers (but not Aristotle!) think that pleasure is the only thing that is good in itself

Key Concept

Endoxic Method: An argumentative structure that begins by laying out the endoxa, or the beliefs of the many or the wise, then raises apparent problems for those views and develops a resolution to those problems.

Key Concept

The Problem of Induction: A problem for reasoning about the future based on past experiences. How can we be justified in believing that patterns of events in the past will continue into the future?

Key Concept

A Priori: Hume is using the term ‘a priori’ to denote the kind of reasoning that allows one to gain knowledge as relations of ideas—in other words, reasoning from one necessary, definitional truth to another.

Key Concept

Justification: the concept of justifying one’s thinking, or one’s beliefs, is important in epistemology. Roughly, one’s thinking or belief is justified when there is good reason for it, or when it is well supported or well evidenced. All of these are ways of referring to some connection between what we think or believe and what is, or to some way of at least making ourselves think that we are closer to the truth.

Key Concept

Inference: The psychological process of moving from one thought to another, such as moving from the thought “it’s raining, and I don’t want to get wet” to “I should get my umbrella”, or from “I am tired, and it’s getting late” to “I should get some sleep”. Nowadays, philosophers tend to use the term ‘inference’ to mean the same as ‘reasoning’, and tend instead to use the term ‘association’ to refer to movements between thoughts that are not based on any logic or evidence.

Key Concept

Matters of Fact: Knowledge that is gained by experience, such as by observing or experimenting with objects in the world. For example, knowing whether all swans in the world are white requires somebody to examine the many swans in the world and make sure they do not happen to discover a black one (and in fact, there are black swans!).

Key Concept

Relations of Ideas: Knowledge that is gained just by sufficiently clear thinking, without having to observe or experiment with objects in the world. For example, knowing that a triangle has three sides is something you can know just because of what it means to be a triangle, hence without having to carefully examine triangular objects that you find throughout the world.

Key Concept

Reasoning: Developing arguments to try and support the truth of one’s beliefs.

Key Concept

Causation: A relation between events, where one event (cause) is responsible for another (effect). Eating too much chocolate can cause the effect of having an upset stomach, and not getting enough sleep can cause someone to be grumpy.

Key Concept

Epistemological Theories: Theories about the nature and possibility of knowledge – whether, when, how, and to what extent we can know about reality, such as the physical world, or our own consciousness. For example, one epistemological theory says that we can gain understanding of our own consciousness by studying the brain, whereas other theories say that we can only gain knowledge of consciousness by reflecting on our own inner experiences. 

Key Concept

Aristotle means “happy” in the sense of a person who has developed a complete character, lived a full life, and become a true example of human goodness.

Key Concept

Happy Person – Someone who has developed her entire self well and lived a complete and flourishing life. She is a real and positive example of how we should live.

Key Concept

This is where Aristotle defines virtuous friends. These are friends who you actually answer the phone for. These are the friends who you ask for advice on work, love, and life. They are the friends that celebrate you for being you, but they also tell you when you’re messing things up. Not only do they love you, but you love them and try to be the same kind of friend to them too.

Key Concept

This is where Aristotle defines pleasurable friends. These are your TikTok, Snap Chat, or Instagram friends, the ones you post to social media when you’re having a good time.

Key Concept

This is Aristotle’s explicit definition of useful friends. These are your LinkedIn friends, those who you like networking with at events or enjoy working with on projects.

Key Concept

Virtuous Friendship – A friendship where people set as their goal for their friendship becoming good people together and living happy lives just because they value the good of their friends as persons. These are also known as “perfect” or “true” friendships. They are usually between people who are equally good. And they might be limited to people of equal social status, wealth, and power. Aristotle doesn’t think that any happy person will lack virtuous friends. But he thinks it’s likely that we’ll only have a few of this sort.

Key Concept

Pleasurable Friendship – A friendship where people set as their goal for their friendship some pleasant goal, such as friendship between people who go out on the town together. These friendships are plentiful and easy to form and dissolve.

Key Concept

Useful Friendship – A friendship where two people set as their goal for their friendship some useful or utilitarian purpose, such as friendship between work colleagues. These friendships are plentiful and easy to form and dissolve.

Key Concept

Aristotle uses “friend” broadly for any relationship between people who like each other, wish good things for each other, and get something out of spending time together.

Key Concept

Friendship – A relationship between two people who like each other, generally wish each other well, and have a goal for their interactions.

Key Concept

Happiness – The final end and highest good of human life. The perfect good that objectively fulfills human nature and subjectively satisfies desire. 

Key Concept

Happiness Criteria – The conditions that the true object of happiness must satisfy. They are: finality, intrinsic value, purity, internality, authenticity, stability, self-sufficiency, completeness.

Key Concept

Object of Happiness – The thing in which happiness essentially consists, the attainment of which will make us truly happy.

Key Concept

Highest Good – The greatest good for a human being.

Key Concept

Final End – The ultimate goal of human life. All of our other goals are chosen for the sake of this final end.

Key Concept

Constituent Principles – Parts of a material object that cause the object to be the sort of thing that it is, but that cannot be removed from that object (in the way that some properties can be gained or lost). For Aquinas, this would include things such as form (the structure of a material object) and matter (that which is structured). For example, Dylan’s form is his soul, and his matter is his body. His soul and body are distinct, but Dylan could not exist if he were not composed of both.

Key Concept

Accident/accidental property – A property that something can possess or not possess while still remaining the thing that it is. For example, Dylan could grow taller, or he could stop being musical, without becoming a different person. By contrast, rationality is an essential property of Dylan, since being rational is part of the “what it is to be” of a human being.

Key Concept

Subject/Suppositum – Something or someone that can bear properties but is not itself a property that something else can bear. Dylan can have properties, like being short or being musical, but no one can have Dylan as a property.

Key Concept

Property – A feature that an object has. For example, a ball could be orange, which means that the ball has the property of orangeness. In many cases a property can be gained or lost. The ball could be painted green, in which case it would gain the property of greenness and lose the property of orangeness.

Key Concept

Actuality – The being, or act of being, of a thing. For example, hot water is actually hot (the water is hot), even though it is potentially cold. Likewise, a boy is actually a human being (he is a human being), even though he is also potentially a full-grown man (and he will still be an actual human being when he becomes a full-grown man).

Key Concept

Potentiality – Ways a given thing can become different from the way it is now. For example, cold water is potentially hot, since it can be heated up, and an acorn is potentially an Oak tree since it can grow to full size under the right conditions.

Key Concept

Essence – The “what it is to be” of a thing. For example, the essence of a human being is to be a rational animal, and the essence of a cheetah is to be the fastest land animal.

Key Concept

Principle of Specialization – The idea that work is more efficient and more effective if each worker specializes in exactly one task.

Key Concept

Extrinsic Value – Value a thing has that is dependent on something else. Extrinsically valuable things are worth pursuing because they get you something else that is valuable. Money, for instance, is only useful because it can be exchanged for other things.

Key Concept

Intrinsic Value – Value a thing has independently or inherently. Intrinsically valuable things are worth pursuing for their own sake.

Key Concept

Adeimantus and Glaucon were Plato’s older brothers (along with an older sister, Potone). They were both honored for military valor at a battle with Megara. We know little about their lives otherwise. Potone had a son, Speusippus, who inherited leadership of the Academy upon Plato’s death.

Key Concept

Thrasymachus was a real person, who lived about 459-400 BCE moved to Athens from Chalcedon to become a sophist (a professional teacher and public speaker). Only a few fragments of his work survives

Key Concept

Prudence – Prudence is virtue wherein a person is able to choose, in any given situation, the course of action that will lead to greater happiness. For example, a prudential person knows when it is appropriate to continue a difficult conversation and when it is best to wait for a more appropriate time.

Key Concept

Pleasure – Epicurus would have us think about pleasure as coming in two forms: moving and static. Moving pleasures are the type that we experience in the process of satisfying a desire (this coffee tastes amazing!). Static pleasure is the feeling of being satisfied — no longer experiencing need or want (I am feeling so peaceful sitting in the park). Epicurus thinks these static pleasures are the best sort.

Key Concept

Epicurus believed that reality  is composed of matter. This sets him apart from other philosophers of the time who, often influenced by Plato, believed that reality is composed of both the material and immaterial (like the soul, or the Platonic forms).

Key Concept

Happiness – Epicurus uses the Greek word “eudaimonia,” which is typically translated into English as “happiness.” Whereas today happiness is most often used to describe a momentary feeling (this new notebook makes me happy!) Epicurus means something more like a consistent state of well-being and contentment.

Key Concept

Unconditioned: an ultimate explanation of reality. For example, if I explain why it is raining today by appealing to some atmospheric conditions, I can always ask for the cause of those conditions, and so on. Only a cause that is not caused by anything else (something unconditioned) would give us an ultimate explanation.

Key Concept

Transcendental Idealism: Kant’s mature philosophical position. It holds that appearances are not things in themselves, but representations of our mind. It is opposed to transcendental realism, which identifies appearances with things in themselves.

Key Concept

Appearances (vs. things in themselves): things as they are experienced by us (also known as phenomena). They should be distinguished from things as they are independently of our experience (things in themselves or noumena).

Key Concept

Metaphysics: the study of what there is. Traditionally, metaphysics is divided into general metaphysics and special metaphysics. The former investigates the general features of reality and asks questions such as ‘What is possible?’. The latter studies particular kinds of being and asks questions such as ‘Does God exist?’ or ‘Is the soul immortal?’.

Key Concept

Reason: the faculty that knows a priori. Kant uses this term in a general sense (the knowing faculty as such) and in a specific sense (the faculty that demands ultimate explanations).

Key Concept

A priori: term denoting propositions that can be known independently from experience. For example, propositions such as ‘All bachelors are unmarried’ or ‘The whole is greater than its parts’ can be known without recourse to any experience.

Key Concept

Make sure not to think that ‘unjustified’ means ‘false.’ Even if they are true, the point is just that this would not be something that had been shown.

Key Concept

‘Absolute’ might be a confusing word, here. Socrates means that the geometers are not reasoning about their drawing of the square, for example, but of the square itself. They do not conclude that, for the square they drew, the area is equal to the square of a side – they conclude that this is true for squares as an intelligible object, or, as Plato would say, the Form of the square.

Key Concept

By ‘science’, Plato means to be talking about all rational disciplines, including mathematics.

Key Concept

The form of the beautiful has to be perfectly beautiful because all instances of beautiful things are explained by it, so it has to be responsible for the highest possible degrees of beauty possessed by anything. Moreover, it has no trace of ugliness in it.

Key Concept

The form of the beautiful has to be immaterial because all the many beautiful things do not share any material – that is, they are all made of different stuff.

Key Concept

Form (εἶδος / ἰδέα) – Intelligible, immaterial, perfect entities that explain the unity among the many things which share the feature named by the entity (e.g., Beauty, Squareness, Oddness). For example, think of a square. There might be many different squares, but they all share features like having four sides of equal length. So, the Form of Squareness would include all of those features that make something a square.

Key Concept

Guardian – This is the name Plato gives to the ruling class in his ideal city. Think of them as philosopher kings – they have complete control over the organization of the state. The Republic is partially about why Plato thinks they would be needed for an ideal system of government and what they would need to learn to do the job well.

Key Concept

Plato has previously argued that we are made up of different parts. The first part is the appetitive which is responsible for our desires for food, sex, and other bodily needs. Then there is the spirited part, which longs for fame and honor. Finally, he identifies the rational part, which discerns what is good and bad for us through reason. The parts can all come into conflict with one another, and managing their relations is what Plato thinks justice is all about.

Key Concept

Soul (ψῡχή) – What Greeks meant by this word is controversial. For now, think of it as the thing that makes you different from a rock or other objects, the thinking and experiencing part of you as well as the part of you that acts and makes decision. You might use the word ‘mind’ or ‘self’ to talk about this.

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Virtue – Virtues are the character traits that make a person good. For example, most people consider courage and generosity to be virtues. English-speakers usually reserve the word ‘virtue’ for human beings, but in ancient Greek the word can be more comfortably applied to other beings as well.

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Was it his burly physique, his wide breadth of wisdom, or his remarkable forehead which earned him this nickname?

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Aporia – A Greek term for “being at a loss” or “clueless.” Socrates often questions people until they have no idea how to define something that they thought they understood.

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You might be confused by the word ‘attention’ below. In Greek the word is therapeia, from which we get the English word ‘therapy.’ It primarily means the same as ‘service’ as in ‘to serve,’ but shades into ‘worship,’ ‘take care of,’ and ‘attend to.’

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Meletus – A poet and citizen of Athens and one of Socrates’ accusers. Amongst other things, Meletus accused Socrates of impiety and corrupting the youth.

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Divine Voluntarism – The idea that God is free to determine even the most basic truths. If divine voluntarism is true, then God could have made it so that 2+2=5 or so that cruelty and blasphemy are holy and good.

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Euthyphro Dilemma – The question, “Is a thing holy because the gods love it, or do the gods love it because it is holy?” The general idea of a forced choice (or “dilemma”) about the true order of explanation occurs often in philosophy and gets referred to by this term.

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Essence – What a thing fundamentally is. A square might be red or blue without changing the fact that it’s a square, but a square must have four sides, so having four sides is part of a square’s essence.

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Definition – The perfect description of a thing. A definition should pick out all and only examples of a thing. For example, ‘bachelor’ might be defined as ‘unmarried man,’ because all unmarried men are bachelors, and only unmarried men are bachelors.

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In Disney’s retelling of the Hunchback of Notre Dame, the clergyman Claude Frollo orders the death of many Roma on religious grounds. It is clear, however, that he is really motivated by spite and his unrequited lust for the Romani woman Esmerelda.

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Spanish conquistadors were shocked by the scope of ritual human sacrifice among the Aztecs, as hundreds or even thousands of people were sacrificed each year. The Aztecs thought that the sacrifices could repay the sacrifices the gods had made in creating the sun and earth.

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Zeus – The god of sky and thunder in ancient Greek mythology, Zeus was depicted as chief among the gods and called the father of the gods and men.

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Forms – The perfect, divine, and intelligible entities that exist independently of the physical world. They are comprehensible only through reason, not through our senses, and their existence explains the properties of objects in the physical world.

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Recollection – The soul existed prior to birth; during this time it learned everything, and hence all learning is only recalling what we already know.

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Immortality of the Soul – Unlike the body, the soul is not subject to physical death, because it is immortal and indestructible.

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Philosophy – The practice of preparing the soul for death by training it to think and exist independently of the body

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Death – Plato understands this as the soul’s separation from the body

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Human Identity Across Time – Locke’s notion that any human stays the same across time if, and only if, it maintains the same (distinctively human) organizing structure of parts.

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Substance Identity Across Time – Something is the same substance across a segment of time if, and only if, it continuously exists across the relevant segment of time without gaining or losing any of its parts.

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Immaterial Soul – A personal thinking substance without any physical constitution.

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Personal Identity Across Time – Whatever makes someone the numerically same person (i.e., that very person) at different times; according to Locke, it is a relation of first-person consciousness via memory.

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Person – Locke’s forensic definition of person (pertaining to courts of law regarding the justice of praise, blame, reward, or punishment): a thinking, intelligent being, that has reason and reflection, and can consider itself as itself, the same thinking thing in different times and places.

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The Prophet Muhammad is a central figure in Islam.  He is viewed as the last of a long line of prophets, which includes Moses and Jesus. He is responsible for writing the Quran, which was dedicated to him by the angel Gabriel.  His life and sayings are recounted in the Hadith; he is viewed as an exemplary role model of Islamic life and faith.

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Exhortation — The method of understanding and interpreting Truth available to the common people. The majority of people take scripture literally and understand truth and right action based upon this understanding. They are persuaded by the vivid imagery of the Quran and the rhetorical exhortations of religious leaders. Averroes takes this to be lowest form of understanding

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Dogmatic Discourse — The method of understanding displayed by those who, through natural ability and habit, are able to have a deeper understanding of the Quran, and of the truths it illuminates. These people know that not all of the scriptures are to be taken literally, and that greater underlying Truths are revealed by interpreting some elements allegorically. Still, they err on the side of dogmatism and literal interpretation whenever uncertainty arises. Averroes associates this way of thinking with Muslim theologians and views this to be the middle level of understanding.     

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Philosophical Inference – The type of understanding associated with philosophical demonstration or argument. This is the highest level of understanding, accomplished by a select few, who have a natural capacity for philosophy and proper philosophical training. 

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Law — The Quran (the central religious text of Islam) and, to a lesser extent, the Hadith (reports of what the prophet Muhammad said and did). Averroes is concerned with explaining how philosophy relates to what Muslims take to be the unerring Truth regarding God and the nature of existence, as they are expressed in Scripture.

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Occasionalism — a theory claiming that God is the only true cause of changes in the world. For example, when you high-five me, you’re not really the cause of the stinging sensation I experience. God is the cause. Your high five is just the occasion on which God causes it.     

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Interactionism — a theory claiming that things in the world can truly cause changes in each other. For example, when you high-five me, you truly cause me to experience a stinging sensation in my hand.

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Substance Dualism — a theory claiming that the mind (or soul) and body are two distinct and very different things.

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Body — what it sounds like! The body is the physical part or aspect of a thing and has characteristics like shape, size, etc.

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Soul — that part or aspect of a thing involving mental aspects of their existence, e.g., thoughts, feelings, decisions, etc. The “soul”, in this sense, is more or less just the mind.

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Causal Interaction — When one thing acts (i.e., itself does something) and in so acting makes another thing change. For example, when you high-five me, you cause me to experience a stinging sensation in my hand.

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God as God – The phrase “God as God” is basically a synonym for “God the subject.” In other words, it refers to God precisely in God’s status as an incomprehensible divine Other.

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Incarnation – The Christian doctrine of the incarnation is the notion that the word of God became fully human in the person of Jesus of Nazareth. It is closely associated with the doctrine of the trinity, which asserts that God the Father, God the Son (Jesus as the word made flesh), and God the Holy Spirit are one God.

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Religious Fanaticism – In Feuerbach’s use of the term, a religious fanatic is someone who is unwaveringly faithful to God as an utterly mysterious superhuman being. They subordinate other things—especially the love of other humans—to submission before this divine other.

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God the Subject – When Feuerbach refers to God as a subject, he is referring to the commonplace religious belief that God is a being who has various attributes, like a loving nature.

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Faith Separates Man From God – Faith separates God from man in this sense: it treats God as a mysterious other, a being radically distinct from us.

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 Faith – Belief in and fidelity to a transcendent divine subject like God.

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Orthodoxy – Orthodoxy refers to “right belief,” and it is concern with identifying heresies and ensuring that people believe and practice correctly.

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Indirect Form of Self-Knowledge – Feuerbach’s view is that religious belief is a naive way of relating to our human nature and its perfections. It is naive or childlike because it treats these as external realities that belong to God. He believes a mature and contemplative person realizes these don’t belong to God, but rather to our species, abstractly conceived.

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Above the Individual Man – The human perfections are “above the individual” insofar as no particular individual ever perfectly realizes them. They are abstractions.

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Divine Trinity – Feuerbach is having fun here. He is using the theological phrasing of the Trinity to talk about human perfections. In calling reason, love, and freedom of the will “divine,” he means they are absolutely good; they are activities whose goodness is intrinsic to their practice or exercise. This isn’t a novel philosophical view. For example, Immanuel Kant argued that autonomy or a good will is the only thing which is unconditionally good.

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Perfections – The end to which a faculty or power is ordered. For example, omniscience would be the perfection of the intellect. Traditionally, God is said to possess all perfections.

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Love – When Feuerbach writes about love, he is referring to unconditional concern for others and the desire for fellowship with them. He is here asserting that love, understood in this sense, is the perfect activity of the affective faculty. In other words, our feelings and passions are fully actualized and engaged in an intrinsically valuable activity when we genuinely love others.

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Infinite – The infinite is whatever can be understood as unbounded or unlimited. Human nature in the abstract is unbounded and unlimited. It is only bounded or limited in its concrete form as it is realized by particular material individuals.

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Higher Consciousness – The sort of consciousness that mature human beings possess, but which other animals do not. It is “higher” than animal consciousness because it involves thinking abstractly about the form or essence of things.

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Science – Feuerbach uses the term science in its classical sense, meaning systematically organized knowledge. Any body of knowledge founded on an understanding of first principles and the essences of things is a science in this sense.

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Popular Sovereignty – The view that a government’s authority to rule comes from the people, making a ruler subject to the will of their citizens.

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The Divine Right of Kings – The theory that kings are chosen by God and thus that political revolt is a rebellion against the will of God.

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Synthesis – The prefix ‘syn-’ means “together,” so a synthesis “brings together” or combines elements of both a thesis and its antithesis.

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Antithesis– An antithesis is the contradiction of a thesis. For example, internationalism could be understood as the antithesis of nationalism.

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Thesis – In Hegelian terms, a thesis can be understood as a position or theory. Examples include any of the “-isms” that we discuss in science, history, and philosophy, such as Darwinism, capitalism, nationalism, etc.

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Progressor’s Temptation – a unique temptation for those making progress in which pride impedes their further progress and leads to backsliding.

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Progressors – those who are not yet expert Stoic practitioners, but who are also aware of the fact that they must change their lives in that direction. They are working on making progress.

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Intellectualism – the philosophical view that our motivations and emotions are all judgments. The reason why you do something, your motivation, is because you believe it’s the right thing to do. The reason why you feel good or bad about something, an emotion, is because you believe that something good or bad happened to you.

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Duties – acts of service, obedience, and respect that we owe to each other. The duties we owe to each other depend on what kind of relationship we have.

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Askeses – exercises of Stoic thought and practice that make the lessons and habits of Stoic philosophy second-nature for Stoic practitioners.

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Externals – things that are not under our control but that are all-too-easily confused with things that should be important to us, like wealth, status, and pleasure. Too many people believe externals like these are necessary for the good life, and the Stoic path is to focus not on these things but rather what is up to us. 

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The Fundamental Division – the division between things that are under our direct control and those that are not. The important lesson is to care only about the things we can control.

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The Greatest Happiness Principle – A principle which says that actions are right insofar as they promote happiness and wrong insofar as they promote unhappiness

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Higher and Lower Pleasures – Types of pleasures that differ in terms of their quality. Things like food and drugs create lower pleasures. Things like intellectual pursuits and doing the right thing create higher forms of pleasure.

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The Doctrine of Swine – An objection that utilitarianism entails that if people would be happy rolling in mud, that’s what would be morally best for them to do, so we should reject the theory.

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Utilitarianism – A normative theory of which actions are right or wrong. Utilitarianism says the right action is that which maximises utility.

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Jeremy Bentham – Considered by some as the father of utilitarianism, Bentham was a moral philosopher and one of John Stuart Mill’s teachers

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Epicurus – an ancient Greek philosopher and one of the first to advocate that the ultimate good is experiencing pleasure and avoiding pain.

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Utility – The thing that is ultimately valuable in itself. For Mill, this is happiness, which he then understands as pleasure and the absence of pain.

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Contract Theory – a modern political theory identifying consent as the sole justification for government. Contract theory is associated with Thomas Hobbes (1588-1679), John Locke (1632-1704), Jean Jacques Rousseau (1712-1778), and more recently, John Rawls (1921-2002)

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Prejudice – a foundational, strongly held, unreasoned (but not necessarily irrational) moral opinion or belief. We might believe, for example, that parents have special obligations towards their own children.

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A Priori – a philosophical term of art meaning (in Latin) “prior to experience,” which refers to knowledge that is innate or arrived at purely through reasoning, like the truths of mathematics.

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Rights – moral claims invoking immunity from (or entitlement to) some specific treatment (or good) from others. Commonly recognized rights include the right to free speech or the right to healthcare. 

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Reform – a change in the social order that originates from the existing character of society. An example would be market-based healthcare reform in a capitalist society.

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Conservatism – a modern political ideology that aims to preserve and promote the existing (or traditional)  institutions of society. These institutions typically include the rule of law, property, the family, and religion. 

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Contingent Being – A being that can fail to exist. Its existence is not guaranteed. This being might come to exist or it might not.

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Necessary Being – A being that can’t fail to exist. Its non-existence is impossible. This also means that such a being has always existed.

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Want to read more about why the infinite regress option doesn’t work in the Second Way? Check out Sean Floyd’s entry in the Internet Encyclopedia of Philosophy.

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Efficient Cause – An efficient cause is something that directly makes another thing exist or move. An example of this is when I kick a ball down a hill. I am the efficient cause of the ball rolling down the hill because I make it move down the hill.

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Infinite Regress: Begin with some fact. We begin to explain that fact by appealing to another fact, where these facts are related by either causality or dependence. To create the regress, you keep appealing to more and more facts about causality and dependence without end.

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Actuality – An ability or action something is currently exercising. Imagine that I am sitting comfortably at my desk, and then I stand up to take a break from reading. In this case, I am now actually standing. 

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Potentiality – What something has the capacity to do, but isn’t currently doing. Imagine I am sitting comfortably at my desk. Even though I’m not currently standing, I have the capacity to be standing. So, even while I’m not standing, I have the potential to stand. 

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Theists and Non-Theists – A theist is someone who believes that God exists, while a non-theist does not. Non-theists include atheists, who believe that God does not exist, and agnostics, who are uncertain about whether God exists.

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Glaucon – one of Plato’s brothers and one of Socrates’ main interlocutors in the Republic dialogue. In that dialogue, he challenges Socrates to provide a compelling justification for why one should be a just person beyond merely following conventions or avoiding punishment. This sets up Socrates’ defense of justice as intrinsically worthwhile. Throughout the Republic, Glaucon prods Socrates to fully explain his theories of the ideal society, philosopher-kings, and the Form of the Good.

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Aristotle – a Greek philosopher (384-322 BC) who studied under Plato and went on to be one of the most influential philosophers to ever live. Simply called “The Philosopher” by Thomas Aquinas and others in the medieval period, Aristotle’s views would eventually be synthesized with Christian theology, laying the intellectual foundation for later scholarly developments in Western Europe.

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Understanding – Socrates describes education as turning one’s “understanding” in the right direction. The word “understanding” here translates the ancient Greek term “to phronēsai,” which means “understanding,” “being conscious,” or “having insight.” People who are wicked focus their “understanding” on how best to accomplish their selfish and narrow desires. Those who are wise, in contrast, have learned to focus their “understanding” on what is truly good and beneficial.

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The Form of the Good – Socrates characterizes the ultimate goal of education as coming to know “the Form of the Good.” The Form of the Good is his technical term for the meaning of goodness: what it is to be good. Socrates is clear that this “knowledge of the Good” is not simply theoretical knowledge, but also knowledge in the sense of “knowing how”: knowing how to achieve what’s good, to do what’s good, to accomplish what’s good. Mere “book knowledge” or simply being smart is not enough.

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The Intelligible – Socrates uses “the intelligible” to name the aspects of the world that we can only grasp through thinking or insight. With my eyes I can see the tree outside my window, but what it means to be a tree is something I can only comprehend in thought. Likewise, I can see the people around me, but human nature, human dignity, and what it means to be human is something I can only grasp conceptually. “The intelligible” is the world insofar as it “makes sense” and can be comprehended.

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The Visible – By “the visible,” Socrates means those aspects of the world we can perceive with our five senses and our imagination—those aspects of the world we can see, hear, taste, smell, touch, and imagine. For example, with my eyes I can see the sky, trees, people around me, and so on as visible things. “The visible” is the world insofar as it can be perceived and imagined. 

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Education – Socrates says that the allegorical story he tells represents the effect of education on human nature. “Education” here is a translation of the ancient Greek word “paideia,” which means “education” in the widest sense of the term. “Paideia” doesn’t mean “education” in the sense of going to school or getting good grades. Instead, it refers to the process of becoming a wise, intelligent, good, and well-rounded human being.

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Allegory – An allegory is a symbolic narrative where characters, events, and/or settings represent abstract ideas or convey deeper meanings beyond the literal story. Socrates tells such a symbolic narrative in the passages below. The characters, events, and setting of his narrative symbolize the effect of what he calls “education.” 

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Self-knowledge – Knowledge of the contents of one’s own mind, such as one’s own beliefs and desires. Self-knowledge can be gained through introspection, that is, by reflecting on what one thinks and experiences. Some philosophers believe that self-knowledge has special properties that our knowledge of the external world lacks, such as being clearer, more reliable, or more valuable.

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Dualism – The view that the mind is entirely distinct from the body. This view is usually contrasted with different kinds of monism, which hold that the mind is ultimately just a part of the body (materialism) or that the body is ultimately just a part of the mind (idealism). Dualists hold that the mind and the body are fundamentally different aspects of reality, and both categories are needed to properly describe the universe, especially the human person. 

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The Self – What the ‘I’ in ‘I am, I exist’ refers to; the part of you that really makes you you. Many philosophers have provided rich accounts of what the self ultimately is, including the soul, the mind, one special feature of the mind (such as consciousness), a mixture of all these elements, or perhaps a mere illusion.  

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The ‘Cogito’ – Descartes’ famous claim ‘I think, therefore I am’ is often referred to as the cogito. The name comes from the Latin rendering of this phrase, which is ‘cogito, ergo sum.’ Descartes held that one can always believe this proposition with certainty. We cannot doubt our own existence, so the cogito survives his exercise of intense doubt. The cogito appears several times in Descartes’ writings, and he often phrased it slightly differently each time. It appears in the Second Meditation as ‘I am, I exist.’

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Certainty – When one believes something with certainty, one is maximally confident that it is true. A certainty is something that is beyond dispute or immune to doubt. Although this captures the basic idea, like many epistemological notions, clarifying precisely what the notion of certainty amounts to is an ongoing area of philosophical research. 

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Vice – A bad habit that we learn over time through instruction or instinct and that we develop through repetition. What makes the habit bad is that, once we have that habit, our tendency is to do the incorrect thing in certain types of situations. We may choose to do something entirely uncalled for in that situation, or we may act at the wrong time, in the wrong way, to the wrong degree, or with the wrong attitudes, or for the wrong reasons.

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Relative Mean – The “Goldilocks amount” of some type of action or emotion. When you act in this way, according to Aristotle, you act exactly as is required under the current circumstances. This means that you do what is called for by the situation at hand, rather than doing something too extreme or not doing something extreme enough. You do something in the moderate amount (the mean amount) relative to the specific situation you are in when you need to act.

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Excellence/Virtue – A good habit that we learn over time through instruction and repetition. What makes the habit good is that, once we have that habit, we have a strong tendency to do the right thing at the right time, in the right way, to the right degree, with the right attitudes, whenever we are confronted with a situation that we know calls us to exercise that habit.

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Doxastic Voluntarism – the view that we have at least some control over what we believe.

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Evidence – information that increases the probability that a claim is true.

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Sufficient – enough of something for a particular purpose. Whether something is sufficient is context-dependent.

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Solon – In the Histories of Herodotus, Solon visits Croesus, the king of Lydia. Even though Croesus shows Solon all of his wealth, Solon refuses to call him the happiest man who ever lived because he does not know how Croesus will die

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Priam – According to Greek mythology, Priam was the final king of Troy during the Trojan War. Despite his wealth and political power, he was killed by Achilles’ son Neopotolemus during the Sack of Troy

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Virtue – The consistent and reliable tendency to perform one’s function excellently. When a person has a certain virtue, like courage, they have spent time developing the habit, in this case reacting to danger well, using their human abilities. The virtues then make it possible for us to live a life of flourishing

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Sardanapalus – An Assyrian king described by the historian Diodorus as living a life of extreme decadence. Sardanapalus indulged himself with food, alcohol, and many concubines, even going so far to say that physical gratification is the purpose of life. Chrysippus said that, on his tomb is inscribed the following: “Though knowing full well that thou art but mortal, indulge thy desire, find joy in thy feasts. Dead, thou shalt have no delight […] I have only what I have eaten, what wantonness I have committed, what joys I received through passion; but my many rich possessions are now utterly dissolved.”

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Function – the characteristic activity of a given thing which makes it what it is. The function of a knife is cutting, while the function of a heart is to pump blood

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Eudaimonia – Frequently translated as ‘happiness’, eudaimonia means the attainment of active human flourishing, and is the end Aristotle identifies as humanity’s highest final good

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Final Good – A good that we pursue for its own sake. Common examples of final goods include happiness, knowledge, and friendship

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Instrumental Good – A good that we pursue for the sake of some other good. A common example is money, as money allows us to purchase other kinds of goods

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Anytus – an Athenian politician, war general, and  one of the primary accusers behind Socrates’ prosecution. Anytus feared that Socrates would undermine the young Athenian democracy he had helped create and defend

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Oracle of Delphi – the high priestess at the temple at Delphi, the oracle was one of the most sought after seers of the ancient world and was thought to relay messages from the god Apollo

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Chaerephon – an ancient Greek from the city Sphettus, Chaerephon is remembered as a loyal friend of Socrates, also making an appearance in two other Platonic dialogues, the Charmides and the Gorgias

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Meletus – A poet and citizen of Athens and one of Socrates’ accusers. Amongst other things, Meletus accused Socrates of corrupting the youth

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Apollo – the ancient sacred site Delphi was dedicated to the god Apollo, an ancient Greek god and the god that Socrates refers to throughout the Apology

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Virtue – a character trait, acquired through habitual practice, that enables one to act well. The virtues can also be thought of as excellences of human character, as they make it possible for us to live a life of flourishing. Examples of the virtues include courage, prudence, and justice

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The Evil Demon Argument – Argues that we cannot hold any of our beliefs with certainty because we could be radically deceived by an evil demon. A classic argument given by Descartes for doubting the reliability of almost all of our beliefs

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Philosophical Skepticism – The position that we do not know many things that we ordinarily take ourselves to know

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A Posteriori Knowledge – Knowledge that can only be acquired through having particular, concrete experiences. Such knowledge can be gained simply through our everyday experiences, or through more complex means like controlled scientific experiments

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A Priori Knowledge – Knowledge that can be gained without having any particular concrete experiences. Such knowledge is typically gained by rational insight or intuition

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Cartesian Method of DoubtA process employed by René Descartes of rejecting all beliefs that he had at least some reason to doubt in order to see if he had any beliefs that he could know with certainty

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Revelation – Theological truths that have been made known by means of some religious text, testimony, authority, or experience, or the act or process in which such truths are made known.

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Rationalism – The view that the only reliable means of coming to know truths about God is reason. As a result, what we might otherwise believe by means of faith ought to be disregarded or even rejected in favor of what we must believe by means of reason.

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Fideism – The view that the only reliable means of coming to know truths about God is faith. As a result, what we might otherwise believe by means of reason ought to be disregarded or even rejected in favor of what we must believe by means of faith.

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Faith – The act of accepting a proposition as true for which there is less than demonstrable evidence, which rises above mere opinion but falls short of logical or scientific demonstration. Faith can also refer to a particular religious tradition or the body of beliefs that are central to that religious tradition.

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Virtue – a character trait, acquired through habitual practice, that enables one to act well. The virtues can also be thought of as excellences of human character, as they make it possible for us to live a life of flourishing. Examples of the virtues include courage, prudence, and justice

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Socratic Ignorance – an awareness of one’s own ignorance, and the reason that Socrates was deemed wise by the Oracle of Delphi. A person who lacks Socratic Ignorance may believe they know many things they actually don’t, leading them to overestimate how well they understand the world

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Apologya formal defense of justification of an action or belief. A Christian apologist, for example, is someone who defends their faith and seeks to justify it through an appeal to reason.

Historical Connection

Solon’s Warning

In the Histories of Herodotus, Solon visits Croesus, the king of Lydia. Even though Croesus shows Solon all of his wealth, Solon refuses to call him the happiest man who ever lived because he does not know how Croesus will die

Historical Connection

Priam

According to Greek mythology, Priam was the final king of Troy during the Trojan War. Despite his wealth and political power, he was killed by Achilles’ son Neopotolemus during the Sack of Troy