Platonic Idealism: Plato and His Influence

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  • 2:13 Allegory of the Cave
  • 4:51 Realm of Forms
  • 8:44 On the Soul
  • 10:21 On Politics
  • 11:35 Plato's Legacy
  • 13:35 Lesson Summary
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Lesson Transcript
Instructor: Max Pfingsten

Max has an MA in Classics, Religion, Philosophy, Behavioral Genetics, a Master of Education, and a BA in Classics, Religion, Philosophy, Evolutionary Psychology.

This lecture examines the philosophy and legacy of Plato. It covers the Allegory of the Cave, the Realm of Forms and Plato's views on politics and the soul. Finally, it shows Plato's enduring legacy in modern science.

Introduction to Plato and His Works

Max: Welcome to Afterlife Tonight. I'm your host, Max Pfingsten. Tonight, our guest is someone truly special: The father of Western philosophy, Socrates' student, Aristotle's teacher, give it up for Plato!

So, Plato, after the people of Athens killed off your master, you got really upset didn't you?

Plato: That's right Max.

Max: How did you deal with that?

Plato: Well, I started a school of philosophy in his honor.

Max: The Academy, wasn't it?

Plato: That's right. I also wrote a lot of books, mostly dialogues, all featuring Socrates. I thought it was important to keep his memory alive.

Max: So was that the point of all these dialogues, to preserve your master's memory for posterity?

Plato: Well, yes and no. Like the pre-Socratic philosophers before me, I was trying to discover the Universals, the Constants, the Laws of Nature. Unlike the pre-Socratics, I was also attempting to live up to Socrates' lofty standard for truth.

Max: We all know how picky Socrates could be about knowledge. I'm pretty sure the only thing Socrates knew was that he knew nothing.

Plato: Exactly right! He insisted that all true knowledge must be logically consistent.

Max: So all of these dialogues were your attempt to explain the world in a simple, logically consistent manner?

Plato: Quite right!

Max: Well, I must admit some of your ideas are profound, others seem rather silly. Yet the sheer volume and completeness of your work have made you the father of Western philosophy.

Plato: That's very kind of you to say.

Max: To cover all of your ideas would take months.

Plato: We've got nothing but time, Max.

Max: True, but our viewers don't. I'd like us to limit ourselves to exploring four of your most famous ideas:

  • The Allegory of the Cave
  • The Realm of Forms
  • The Nature of the Soul
  • and The Ideal State, which you called The Republic

Plato: Sounds good to me.

The Allegory of the Cave

Max: Let us start with what I believe to be your most profound idea: The Allegory of the Cave. Take it away, Plato!

Plato: Imagine a group of people who have lived their whole lives in a cave. From their childhood, they have been sitting, chained, unable to move even their heads, facing the rear wall of the cave. Behind them blazes a bright fire. Behind the fire and the prisoners runs a barricade. From behind that barricade their captors have been making shadow puppets on the wall of the cave.

As a result, the prisoners' knowledge would be limited to the shadow puppet show they had seen on the wall. They would believe these puppet shows to be reality.

Then, one day, a clever fellow escapes from the cave. And as he steps out into the sunlight, he realizes that everything he's ever known was but an illusion.

He tries to free the other captives. But they don't believe in the world he describes, since they don't know anything but shadow puppets. They actually get quite upset when he tells them that their entire world is not real. In the end, the enlightened hero is killed by the very people he's trying to save.

Max: That sounds a lot like Socrates. He tried to free people from their mistaken opinions and got killed for his trouble.

Plato: Indeed.

Max: So, Plato, what are we to make of this allegory, besides being an homage to the great Socrates?

Plato: Well, I wrote this metaphor with two points in mind. First, to help people imagine what it would be like to be deceived by their own senses. Second, to demonstrate Socrates' most important idea: the difference between opinion and knowledge.

You see, opinion is only true in certain circumstances, whereas knowledge is universally true. Opinion changes constantly, whereas knowledge is constant and always true.

Max: So the things the prisoners believe are opinions. They are only true in their shadowy prison, for they are based on their observation of an illusion. But the things the enlightened man knows are knowledge. They are universally true, for they are based on observations of the real world. Overall, our opinions constrain us while our perceptions deceive us. By trusting only in our senses and insisting that our opinions are true, we blind ourselves to true knowledge. Is that about right, Plato?

Plato: That is essentially the Allegory of the Cave.

The Realm of Forms

Max: So, Plato, what is this true knowledge, since you're so enlightened?

Plato: True knowledge is not something readily perceived by our senses. When we look at the world around us, we see inconsistencies and changes taking place constantly. Things are always moving and changing. Tides come and go, stars come out, only to flee again, rivers devour mountains, and even the hardest steel will collapse to rust. All living things age and die.

But knowledge does not change. Knowledge is always true. Thus, we cannot acquire true knowledge based on observations of the natural world. No, no. Instead, knowledge is accessible only through pure reason and thought.

Max: Hold on there, Plato. So you're saying that we can't find knowledge by observing the world around us?

Plato: Absolutely not. Knowledge does not change, the world does. Therefore, the world is no place to look for knowledge.

Max: So where should we look for knowledge?

Plato: The Realm of Forms

Max: And what's that?

Plato: So, here's the earth. What a sweet earth, you might say. Wrong! Just look at it, it's constantly falling apart and reassembling itself. Trees are growing, rivers are flowing, giraffes are dying.

Max: So what's the alternative?

Plato: In the Realm of Forms, nothing changes. Everything is always perfect, always as it should be. In the realm of forms, trees don't grow, rivers don't flow, and giraffes never die. Things just are. The earth, and everything in it, is just a shoddy copy of the realm of form. The tree, the river, the giraffe, they're just matter being shoved temporarily into an eternal form.

Max: Like Jell-O in a mold.

Plato: If you say so.

Max: Just trying to be helpful.

Plato: Please don't. As I was saying, everything in the world is a poor copy of an eternal form. There's the perfect form of tree, a perfect form of cat, a perfect form of human. All the varieties we see in trees, cats, and humans result from the imperfect mechanisms of nature trying ineffectively to copy these perfect forms.

Max: So let me see if I've got this straight. When, say, John the Craftsman builds a wheel, he imagines the perfect form of a circle, which he uses as a blueprint. He then tries to copy this form in the natural world.

However, John's skills and tools are imperfect. Try as he might, he can never create a perfect circle. Moreover, even the best craftsman is limited by what he has to work with, and the materials of the natural world are imperfect. Whatever John makes the wheel out of, it will never be perfectly round, even if it seems so to the naked eye. Moreover, it will eventually wear down and fall apart with time. The resulting wheel is, at best, a rough approximation of the eternal form of circle.

So the perfect circle does not exist in this world. The only time John really sees the perfect form of a circle is in his imagination.

Plato: Exactly!

Max: And there are forms for every object on earth: people, dogs, trees, and even circles.

Plato: But not just forms of objects, there are forms of ideals. There is a perfect form of justice, a perfect form of love, a perfect form of government. Yet these are just as unattainable in the material world as perfect circles or perfect humans. As poor copies of the perfect human form, it is not surprising that we imperfect humans struggle to achieve the perfect form of justice.

Plato on the Soul

Max: This all seems like quite a stretch to me. An eternal, unchanging world that we cannot perceive seems like a lot to ask a rational person to swallow.

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