Plato’s Philosophy: Life, Theory of Ideas, and Dialogues

Posted on Feb 25, 2025 in Philosophy and ethics

Plato’s Life and Philosophical Project

If Plato’s family belonged to the Athenian aristocracy, they claimed descent from the gods. By doing this, the aristocrats sought to ensure the superiority and the natural character of their excellence (virtue). In his life, Plato met Socrates, to whom he remained devoted until Socrates’ death. Plato’s most formative years were spent in Athens during a turbulent political period. The government, under the oligarchic rule of the Thirty Tyrants (among whom were relatives of Plato), instilled in him a deep distrust of politics. Although initially inclined towards a political career, the reign of terror and the condemnation of Socrates led to disillusionment. Plato considered politicians corrupt, and his philosophical project aimed to create a state where the death of Socrates would be impossible.

Plato’s Theory of Ideas

Plato sought to provide definitions, but argued that one cannot define something that is continuously changing. He proposed that definitions apply to another type of being: Ideas. He added that sensible things are separate from the Ideas, and all things partake in the virtues of the Ideas, sharing the same name as those Ideas.

Early Dialogues

In his early dialogues, Plato seeks the definition of virtue. While some might say there are as many definitions as there are men in the world, Plato argues that there must be something common to all acts of courage that defines value. This common element is called an Idea. In this context, Ideas have an ethical intention, and one must know what each virtue is.

Dialogues of Maturity

Here, we find assertions such as: if something is beautiful, it is not beautiful in itself for any other reason, but is beautiful because it partakes of beauty. All things are beautiful because they partake of beauty. Plato provides different sections:

  1. The Ideas are the essence by which a thing is what it is.
  2. The Ideas exist outside of particular things. They are entities that have an independent real existence, not merely concepts or mental representations.
  3. The doubling of the world: the visible world of things and the intelligible world of Ideas (Myth of the Cave).
  4. Each Idea is unique, eternal, and immutable. There is only one eternal beauty, always the same. Ideas are not only corporations but intelligible realities made by intelligence.
  5. The relationship between Ideas and things: a thing has participation in an Idea. The Ideas are the cause of things, and reality is simply a reflection or imitation of Ideas.
  6. Plato introduces two intermediary worlds: mathematics and the soul.

The Ideas are the subject of concept or thought; they are designated by the word, the object of definition, and therefore of science. Something is beautiful can be defined as such and conceived as beautiful. The theory has a political intention, stating that rulers need to be philosophers, and a scientific intention, stating that science can only be about Ideas.

Critical Dialogues

Here, Plato reviews the theory of Ideas, asking questions such as:

What kinds of Ideas are there?

The theory implies that there must be an Idea for each common name, but in his first dialogues, Plato refers only to a few types of Ideas and now seeks to provide Ideas for even ridiculous things.

What is the relationship between Ideas and things?

There is no resemblance between Idea and thing, which suggests other Ideas beyond the initial Idea, which would be like the first Idea and things, and infinitely so (the Third Man argument). Plato argues that the Ideas have to continue to exist because otherwise there would be no direct object of thought.

Is there some relationship between Ideas?

Plato attempts to establish a hierarchy between the Ideas, but the supreme Idea has not always been the same. He tries to establish a certain combination between Ideas without losing their identity. The Ideas of motion and rest are not related, but they are related to the supreme Idea of Being.

What relationship between Ideas and numbers?

The question arises whether Plato assigned numbers to the Ideas or if the numbers were a compromise between the Ideas and things.