Platonic Ethics and Classical and Christian Theism, Part 3


In my first  two posts, I reviewed Plato’s requirements for a truly objective morality and then showed how Judeo-Christian theology meets his four requirements, providing a solid foundation for objective morals. With an objective foundation for morality in place, the big question becomes, “Why should I care?” Just because objective morals exist doesn’t necessarily mean I sufficiently want to obey them. This is the issue of moral motivation, and, unsurprisingly, Plato addresses this topic as well. In this post, I’ll take a look at the three levels of moral motivation that Plato describes in the Republic.

I’ve actually been working backwards in these posts. In the Republic, the question of moral motivation is the subject of Book II and the starting point for the investigation as to what justice (the Good) really is. After Socrates defeats Thrasymachus’s philosophically unsophisticated challenge that justice is merely “the advantage of the stronger” in Book I, Glaucon doesn’t let Socrates off the hook that easily, immediately challenging him to show why one should want to be just. While Plato asserts that justice is good in and of itself and good for the one who practices it, Glaucon responds:

Well, that’s not the opinion of the many…rather it seems to belong to the form of drudgery, which should be practiced for the sake of wages and the reputation that comes from opinion; but all by itself it should be fled from as something hard.[1]

Glaucon persuasively recites some popular arguments against acting justly, saying that it is best merely to appear just (so you can enjoy the benefits of a good reputation) rather than to actually practice justice—if you can get away with it. Given this popular opinion, why should one want to be good? Plato has three reasons, corresponding to three levels of moral motivation.

  1. It Is Good to Love the Good because It Is Good

As discussed before, in the Euthyphro the pious was loved by the gods because it was (obviously) pious.[2] It had an innate loveliness that impelled the gods to love it. Likewise, the Good is loved by the gods because they directly experience its goodness and cannot help but to love it. Plato describes this concept the most thoroughly in his Symposium where people are drawn to the Beautiful through a form of eros, erotic love. John Rist brings the point home well:

The Socratic person, as we have seen, is a philo-sopher, a lover of wisdom, an erotikos, as has been emphasized in the Symposium…. His knowledge of the Form is inseparable from his love of it; he is as committed emotionally as he is intellectually to the world of Forms and the Good; his mind is not that of a Cartesian calculator, but of a Socratic lover.[3]

The first and highest form of moral motivation is love of the Good. Those who experience the form of the Good directly—the gods for Plato—are captivated by it and happily arrange their actions according to it because of their love for it. If men could see the Good directly, they would always want to do good. Unfortunately, they do not. What then are we mortals to do? What should compel us to do good even if we do not have this love for the Good? We should do good because it is good for us.

  1. It Is Good to Do the Good because It Is Good for You

In the middle of Book II, after repeating the common man’s argument that it is best to act unjustly as long as people believe you to be just, Glaucon sets up the main challenge for Socrates that drives the rest of the book:

So, don’t only show us by the argument that justice is stronger than injustice, but show what each in itself does to the man who has it—whether it is noticed by gods and human beings or not—that makes the one good and the other bad.[4]

In effect, Glaucon wants to know what makes practicing justice good for the soul and practicing injustice harmful to one’s soul—this is the main question of the Republic. Through his investigation of the best and worst types of cities, Socrates is really discovering the best and worst types of man.

The very worst city corresponds to the most miserable man—the tyrant. This person, even if he enjoys wealth and good reputation (wrongly), is the most miserable because the turmoil in his soul will not allow him to enjoy the good things that are available to him. He is more a beast than a man. He cannot enjoy the best pleasures of this life because those enjoyments are experienced through our rationality and the tyrant has debased himself in this area. Because of the defilement of his soul, at best he can enjoy animal goods; but, because of his injustice, even those things cannot satisfy him.

On the other hand, the very best city, ruled by the philosopher-king, corresponds to the very best type of person: he who lives justly, who does the Good and can truly enjoy it. Because he is trained in philosophy, his rational abilities are honed and he can truly enjoy the best—the most human, or, better, the most divine—pleasures. Even if this person does not have material possessions, and if his fellow citizens do not understand him and hence mistreat him, his intellectual pursuit of and love for the Good make him the happiest man of all.

John Stuart Mill captures the difference between these two types of people in his famous quote:

It is better to be a human being dissatisfied than a pig satisfied; better to be Socrates dissatisfied than a fool satisfied. And if the fool, or the pig, are of a different opinion, it is because they only know their own side of the question.

The pursuit of, and adherence to, the Good leads to the very best life, whether or not that life is accompanied by material possessions and the acclaim of men. For Plato, Socrates was the prime example of this. The pursuit of injustice leads to the worst possible life for a person. Even if it is accompanied by riches and fame, the debasement of the soul that it causes leads the unjust man to a truly miserable life, whether or not he realizes it.

So, for the rational person there are two good reasons to be moral: love of the Good is good in and of itself, and the Good is also good for you. In his Finite and Infinite Goods, Robert Adams similarly argues that what is best for us is what is good in and of itself. But what motivates the person who is acting irrationally?

  1. It Is Good to Do Good because the Just Will Be Rewarded and the Unjust Punished

In the early dialogues, Socrates teaches, and Plato appears to hold, that people will never knowingly do the worse when they know the better. In his middle and later dialogues, Plato appears to move away from this position and deal with the problem of akrasia, where people know the good to do but choose the worse. How are people motivated when they know the Good is good, and is good for them, but they still choose to do the worse? For these people—who are more like unreasoning animals than men—rewards and punishments must be offered to motivate them.

In Book II Glaucon challenges Socrates to show that acting justly was beneficial even if it was accompanied by poverty and scorn, and Socrates argues his case with this restriction in place. In Book X, Socrates asks Glaucon to let him correct this injustice and show that the just man will receive good for acting justly: “Thus, it must be assumed in the case of the just man that, if he falls into poverty, or diseases, or any other of the things that seem bad, for him it will end in some good, either in life or even in death.”[5] In this life, Plato believed that the just will typically receive rewards for the good that they do and that the unjust will typically receive punishment for their injustice; however, if it does not happen in this life, Plato had a story for what would happen to the just and unjust after this life.

Book X ends with the myth of Er, a valiant warrior who died in battle but came back to life after twelve days and shared what he saw in the “other world.” There, the just and unjust went through a period of 1,000 years of either rewards or punishment for their deeds. The just “told of the inconceivable beauty of the experiences and sights” in heaven, while the unjust “lamenting and crying, [recounted] how much and what sort of things they had suffered and seen in the journey under the earth.” While the common unjust suffered for 1,000 years, men who were tyrants, after suffering for that same duration, were bound and thrown into Tartarus, never to emerge. This is Plato’s message for those who would practice injustice, and the message “could save us, if we are persuaded by it, and shall make a good crossing of the river of Lethe and not defile our soul.”[6] If nothing else will motivate one to be just, they must be coerced with either the hope of reward or the fear of punishment.


So for Plato there are three levels of moral motivation. The first and purest is to be good because of a passionate love for the Good itself; this is the best, and only truly moral, type of motivation. For those who are too short-sighted to make the philosophical investment to know the Good directly, the second is to be good because doing justice is good for you—more importantly, it is good for your soul. This motivation leans more towards the self-interested side, but at least it remains a form of internal motivation. Finally, for those who will not strive to do even what is good for them, the third form is either to bribe with promises of rewards for acting justly or threaten with punishment for the unjust. This form is not strictly moral motivation, but, given the problem of akrasia, it is necessary to get some to act rightly in a world that is moral to its core.

In my next post, I’ll take a look at how Plato’s moral motivation compares with Judeo-Christian theism’s and briefly contrast these views with moral motivation typically found in certain naturalistic ethical systems.


[1] Plato, The Republic, Book II, 358a.

[2] Plato, Euthyphro, 10a, d.

[3] John Rist, Plato’s Moral Realism, p. 150.

[4] Plato, The Republic, 367e.

[5] Plato, The Republic, 613a.

[6] Plato, The Republic, 621c.

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