Plato's Theory of Ideas

We explain what Plato's theory of Ideas is and what its formula consists of. Also, criticism according to different thinkers and more.

What is Plato's theory of Ideas?

The theory of Ideasalso called theory of forms, is a philosophical theory attributed to Plato (427-347 BC) that affirms that there are two types of realities:

• The sensible realitywhere sensitive entities are found, which are those that can be perceived with the senses, such as a tree, people and all inanimate objects.
• The intelligible realitywhere intelligible entities called “Ideas” live, which are those that cannot be perceived through the senses, but only through reason, such as piety or goodness.

Sensitive reality and intelligible reality are related as if one (the sensible one) were a copy of the other (the intelligible one). Plato called this way of relating imitation: sensitive entities imitate to the intelligible Ideas, which are the ideal and perfect models of all things. Another way in which they are linked is through the stake: sensitive things participate of the Ideas, as if they took a part of them and reproduced it.

Plato never presented this theory in a systematic and complete way, but he did introduce it in his dialogues to answer certain questions and thus explain other phenomena. This resource is characteristic of all of Plato's dialogues. The three dialogues that best respond to and explain the theory of Ideas are The Republic, Phaedo and Phaedruswhich are his mature works.

The theory of Ideas is considered the core that articulates all Platonic thought.. Likewise, most of the philosophers who followed Plato referred in one way or another to the theory of Ideas, to rely on it or harshly criticize it, as was the case of Aristotle.

See also: Plato

The initial version of the theory

The first version of this theory has its origins in Plato's early dialogues, as Laches, Euthyphro and Menon. There, it is proposed that the Ideas are the true response to each definition requested by the participants of the dialogue. Generally, these definitions are asked by Socrates when asking the question “What is X?” This allows Plato to develop his theories.

In the dialogues, Plato characterizes the Ideas as universal, since they are definitions shared by all individual cases, as opposed to sensible entities, which are the concrete cases, which Plato calls “the particulars.”

So, things designated by the same name and characterized by the same properties respond to a single Idea (eidos either idea, in Greek). For example: all pious acts respond to the Idea of ​​piety, while things are beautiful because they imitate the Idea of ​​beauty. This allows the universal to function as a paradigm from which a particular can be characterized.

Characteristics of Ideas according to Plato

In mature dialogues (such as Phaedo, The Republic and Phaedrus), Plato maintains that Ideas are a set of intelligible entities that are characterized by being:

• Unique. Ideas have their own characteristics, no two are alike. For example, beauty is not the same as any other Idea.
• Numerically one. Each Idea is one in itself. For example, the Idea of ​​good is only one, although many things are good.
• Eternal. Ideas have no beginning or end, unlike sensible things. For example, the Idea of ​​piety does not end when pious acts disappear.
• Self-identical. Ideas always remain the same as themselves. For example, the Idea of ​​courage does not change with each act of bravery, it is always the same.
• Pure Ideas are “cause” or “model” of particulars, which are sensitive and degraded copies. For example, the Idea of ​​justice is a model of all just acts.
• Uncomposed. Ideas are not composed of different elements. For example, the Idea of ​​kindness is not composed of every kind act.
• Homogeneous. Ideas are homogeneous for sensitive entities. For example, the Idea of ​​beauty present in all beautiful things is the same, even when the beautiful things are different from each other.
• Unaffected by the generation and corruption of sensible things. Ideas are in an autonomous sphere and separate from the sensible sphere, in which individuals are found.
• Entities in and of themselves. Ideas do not depend on other entities, they are autonomous. For example, the Idea of ​​what is just does not have just acts as its cause, it is independent of them.

See also: Epistemology

The Third Man Argument

The argument of the third man has been much discussed by all specialists in Plato's work. Even Plato's own disciples ended up questioning it, since it presented a series of problems that were difficult to resolve.

All the criticisms have focused on how, From the separation between sensitive entities and Ideas, which are linked by repetition and imitation, an infinite regression of Ideas emerges.. This means that, due to the way in which sensitive entities relate to Ideas, it can be thought that there is always an Idea behind each Idea, making it impossible to reach the original Idea.

Aristotle, for example, maintained that the Idea of ​​“man” applied to men as particular individuals sensitive to certain properties. If the Idea itself possessed these properties, explaining it would involve appealing to a new Idea. Consequently, the Idea of ​​“man,” as long as it was separated from what it referred to, was a “third man.”

The problem was not only in this second duplication, but also in the fact that from this third man predicated of the first two a fourth man could be predicated again, so an infinite regression was generated. So, By understanding that Ideas, as qualities of things, could exist on a separate plane, this resulted in an unnecessary and infinite repetition of entities.

Aristotle's criticism

Aristotle (384-322 BC), one of the most important philosophers not only of the Greek world but of all time, was a disciple of Plato. However, he criticized his teacher's work and took a position that for some is considered contrary to Platonic thought.

Aristotle shared the conception of the Idea or form as the cause of being and the knowledge of things, but he criticized the notion of “separation” as one of the problematic axes of Plato's work.

Aristotle's commentary can be summarized in four main points, which focus on the causal function that Ideas can exert on sensible things:

1. Criticism of duplication. Plato introduced Ideas as entities distinct from material things. This resulted in a duplication that, according to Aristotle, instead of simplifying reality, made it more complex.
2. Criticism of the arguments. Aristotle maintained that the arguments in favor of Ideas were fragile, they did not prove their existence, but only demonstrated the existence of Socratic universals, which were general definitions given in the field of grammar.
3. Criticism of insufficiency. For Aristotle, Ideas could not satisfactorily explain sensible reality.
4. The inconsistency in the modes of relationship. For Aristotle, none of the modes of relationship that Plato established between the sensible world and the intelligible world (that of Ideas), that is, participation or imitation, was sufficient or consistent to explain the link between one and the other.

References

• Guthrie, W. (1988). History of Greek Philosophy, vol. IV. Plato, the man and his dialogues: first period. Gredos.
• Guthrie, W. (1988). History of Greek Philosophy, vol. V. Plato, second period and the Academy. Gredos.
• Guthrie, W. (1953). The Greek philosophers. From Thales to Aristotle. FCE.
• Ross, W. D. (1993). Plato's Theory of Ideas. Chair.
• Cordero, N. (2008). The invention of philosophy. An introduction to ancient philosophy. Byblos Publishing House.
• Aristotle, & Yebra, VG (1970). Metaphysics. Gredos.