[MUSIC] In book five of the Republic, Socrates shocks Glaucon by announcing that the rulers of the properly governed city must be philosophers. He explains by defining who he has in mind as a philosopher. In doing so, he introduces what is come to be known as Plato's Theory of Forms. And he gives a further explanation of the difference between knowledge and belief. Now, the distinctive feature of the philosopher, he explains, is the belief that there exists such things as what he calls the beautiful self, or the just itself, or the good itself. Socrates refers to these things as forms. We can think of these forms as answers to the sort of question that we routinely see Socrates investigating in Plato's dialogues. What is piety? What is virtue? What is courage? What is justice? In each case, he is looking for some one thing that is first of all the same in all cases of piety or virtue or courage or justice. And second, what makes things pious or virtuous or courageous or just. This one thing will be what he calls The Just itself or The Pious itself and so on. When Socrates asks, what is justice or what is piety, or in other dialogues, what is courage or what is temperance? His interlocutors are usually able to come up with lots of examples of justice, or piety, or courage or temperance. For example, Euthyphro proposes that prosecuting injustice is pious. Polynicus proposes that returning what you've borrowed at the appointed time is just. And Laches, in another dialogue proposes that standing your ground in battle is courageous. These are examples of what Socrates calls The Many pious things, or The Many just things, or The Many courageous things. They are many in the sense that there are lots of instances of them. There are many different times where a soldier stands his ground under enemy fire. Many different cases of returning what you've borrowed. And many different cases where a wrongdoer is brought to trial. There are also many in a different sense. They are just one of the many kinds of things that are courageous. Or one of the many kinds of things that are pious, or just. Standing your ground under fire may be courageous, but so is infiltrating behind enemy lines. Prosecuting injustice may be pious, but so is honoring your parents. When Socrates asks what is piety or what is courage or what is justice and so on. In general, we can what is X. He's looking for someone thing that is the same in all cases of X. So citing one of the Many Xs won't satisfy this demand. The Many Xs also suffer from a further deficiency that Socrates emphasizes here at the end of book five of The Republic. The many just things for instance are no more just than the opposite. The many pious things are no more pious than impious. The many courageous things are no more courageous than the opposite. Consider the case of prosecuting the wrongdoer. This is sometimes pious, perhaps even most of the time it's pious, but not when the wrongdoer is your father. So prosecuting the wrongdoer, considered in and of itself, is no more pious than impious. Similarly, for returning what you've borrowed, it is sometimes the right thing to do, probably most of the time, but not always. If you've borrowed weapons from a lender who has become insane and homicidal, it is wrong to hand them back, even if you've promised to do so. That's the example from Republic One. So returning what you've borrowing isn't in and of itself just. And similarly, if we are looking for something that in and of itself makes an act courageous, standing your ground under fire won't do. Since if a tactical retreat is called for, standing your ground isn't courageous, but stupid. So that's why, as Socrates says, the many Xs always fail when proposed as an answer to the question, what is X? Now, you might take as the moral from this failure, which we see repeated over and over again in Plato's dialogues. You might take the moral as that there is no such thing that satisfies Socrates' demands. Something that is the same in all cases of x, that makes all cases of x cases of x. You might conclude that there is no such thing as what justice is, in and of itself. There are simply lots of different just things. That there is no such thing as what piety is, in and of itself, just a lot of different pious things, and so on. But this is to give up on the project of philosophical inquiry as far as Socrates is concerned. It is as wrong headed as a slave in the Meno throwing up his hands about the length of the side of the eight foot square, after he's exhausted all of the possible answers in his repertoire. It's not two, or three, or four. Recall that the correct answer to the question in that case does not involve giving a number, but pointing to the line. And remember keeping an open mind about what would count as an answer to a question and where it is to be found. Is one of the morals to draw from the demonstration of recollection and the Meno. Socrates thinks that those who passionately believe in the possibility of knowledge, of finding an explanation that will tie down our various true beliefs about X, will persistent in trying to find the answer to the what is X question. But we'll conclude that it is not to be found in a sensible world, in the world of our everyday experience, the world of the many Xs, the world with which we are familiar and have a vocabulary to describe. Rather what justice is, what piety is and so forth, are accessible only to the intellect. These forms are the objects of recollection. The items that our souls have encountered in a previous disembodied form, according to the theory of recollection as it set forth in the Meno and the Phaedo. According to the theory of recollection, the philosopher's practice is to try to regain contact with these forms using the intellect, or power of reasoning, rather than the senses. By contrast, those who believe only in what we can see or hear or touch or taste, these are the ones he calls the lovers of sights and sounds. Believe there are only the many beautiful things, but nothing that is what beauty is in and of itself. That there are only the many just things but nothing that is what justice is in and of itself, and so on. That's all there is to beauty, justice, goodness, and the like. This attitude is one that Socrates, borrowing an image from Heroclytes, likens to the delusion of dreamers who don't realize that they aren't awake. He asked Glaucon, what about someone who believes in beautiful things but does not believe in the beautiful itself? Do you think he is living in a dream, or is he awake? Just consider, isn't it dreaming to think, whether asleep or awake, that a likeness is not a likeness, but rather the thing itself that it is like? Glaucon agrees. Someone who does that is dreaming. So here's the moral of the story. Those who have not grasped what justice is, in and of itself, will never have any knowledge about justice. Whatever true beliefs they may have about justice are not tied down by any understanding of what makes things just. And so their beliefs will be unstable, liable to wander away when they encounter even the flimsiest challenge. And their superficial understanding of justice is likely to lead them to the wrong answer or give no guidance at all in many cases. If all you have is belief about justice, not knowledge, you could get things right, or you could just as easily get them wrong. That's what Socrates means when he says that belief, which is all the sight and sound lovers have, is directed at what is and is not. While only knowledge is reliably directed at what is.