Plato’s Theory of Ideas: A Dualistic Perspective
Plato’s Theory of Ideas
The Theory of Ideas affirms the existence of certain intangible realities: conceptual, immutable, innate, and everlasting (eternal). These are absolute, transcendent, not accessible to the senses but to intelligence, separate and independent of the physical world of sensible things and human views. Ideas are also ideal paradigms or models that are the essences of things, and are imitated by them more or less imperfectly, the way a shadow copies or imitates the object that produces it.
Philosophical Context
The City of Athens had always been ruled by oligarchs. Since the sixth century BC, democracy was established, a political system in which citizens have a say (foreign women, slaves, children, etc., were not considered citizens). After a century, the plight of Athens, due to internal conflicts among the oligarchs and the democrats, weakened the polls and already declared war between Sparta and Athens, the Peloponnesian War, in which Athens was defeated. Sparta introduced a regime governing the polis of 30 oligarchs. This very short period is known as the rule of the Thirty Tyrants. Because of the great injustices and repression committed by the government against the Democrats, the leader of the Democratic side organized a revolt in which democracy was restored, and Socrates, considered the most righteous man in the world, was put to death. Plato was born in a time marked by political instability and military conflict. A member of a family with political possibilities, he wanted to dedicate his life to it and met his teacher Socrates, who introduced him to the world of philosophy. The great injustices perpetrated by the government of the Thirty Tyrants and the death of his teacher Socrates under the government of the Democrats made him realize that philosophers must govern since no government would be just if the rulers did not know what is fair and good. Hence, the doctrine of the philosopher-king was born.
Ontology: Sensible and Intelligible Worlds
The Theory of Ideas is based on the distinction between two basic levels or degrees of reality. This is what is called ontological dualism:
- a) First, the level of the truly real, also called the intelligible world or the world of Ideas. It is a world of abstract realities, eternal, perfect, immutable, immaterial, and accessible only to intelligence. Ideas are organized hierarchically, so that on top of them all is the Supreme Good Idea. The idea of property is metaphorically symbolized by the sun in the myth of the cave (Parmenides).
- b) Moreover, reality is the sensible or visible or physical world. It is the world of objects we perceive through our senses. It is a world of material things, which are born and die, apparently imperfect, and subject to change. For this reason, it has less reality than the ideas. Ideas are the essences of sensible things. The essence of a thing is what makes a thing what it is.
In short, Plato expresses the relationship between the sensible and intelligible world with the terms participation or imitation. Thus, sensible things copy or imitate Ideas, or sensible things participate in the Ideas. Ideas are therefore the cause of being and existence of sensible things; they are the perfect model that sensible things copy or imitate imperfectly. What things are sensitive to is actually due to the ideas involved, so we can say that a relation of ontological dependence of things on the Ideas exists; sensible things are ontologically dependent on Ideas that are their essence (noesis is the highest level of ontology).
Epistemology
Plato advocates the existence of two different levels or degrees of knowledge. This is what is called epistemology or epistemological dualism:
- a) Scientific knowledge or episteme: The aim of knowledge must be to offer a clear, objective, and true reality. The real is truly stable, immutable, and eternal, i.e., the world of ideas, which are the essence of things. To achieve real knowledge of what our soul must be directed to, the contemplation of the eternal Ideas, away from the deceptive ways of changing things and the sensible world. Achieving this kind of knowledge is the goal behind philosophy. Once reached, the philosopher knows the idea of something and also knows sensible things that copy the idea. In short, scientific knowledge or episteme represents the top level of knowledge and shows us the real truth, as it concerns what is truly real, i.e., of the Ideas. Unlike simple opinion, it is infallible, universally valid, objective, unchanging, and is based on intelligence, not the senses.
- b) The opinion or Doxa: It can only be a sensible opinion. The Sophists argue that any opinion is relative. The sensible world copies the intelligible world; we review a bit closer to the intelligible realities which constitute the model and the essence of the sensible. In short, the view represents a lower level of knowledge. It aims at the world of sensible things and changing materials, which are only single copies of Ideas. It is relative knowledge, seemingly superficial, unreliable, linked to the senses and sensible appearances. Moreover, just as its object is changing.
The Simile of the Line: Ontology and Epistemology
The core of Platonic philosophy is the distinction between two levels of reality (intelligible world and sensible world), which correspond to two different levels or degrees of knowledge (scientific knowledge and opinion).
In summary, using the simile of the line, Plato makes a clear relationship between ontology and epistemology. Through it, he seeks to communicate four important ideas:
- a) The existence of different degrees of reality, according to a scale from lowest to highest degree of reality: 4. images, 3. natural and artificial beings, 2. mathematical objects, 1. IDEAS.
- b) The existence of different degrees of knowledge, according to a scale from lowest to highest degree of clarity or truth: 4. imagination, 3. belief, 2. thinking, 1. intelligence (or knowledge).
- c) The existence of a correspondence between levels of reality and levels of knowledge, so that the more real an object is, the clearer and more true is the knowledge we can gain from it, and vice versa.
- d) In its gradual ascent towards the ideas, the soul must traverse all levels of being, rising from the images to the Ideas, via two intermediates (physical objects and mathematical objects).
Man: A Compound of Body and Soul
Plato has a dualistic conception of man: man is a composite of body and soul. This is anthropological dualism. However, the union of soul and body is seen as a punishment.
- a) The soul is considered immortal and immaterial; it is what constitutes ourself, our true self. Plato said that man is his soul. Plato sees the soul as the vital principle that gives life and movement to the body, but it is also the beginning of knowledge. The specific function of the human soul is knowledge, and its most characteristic feature is its rationality. The soul is a reality somewhere between the two worlds (sensible and intelligible) that belongs to the world of Ideas, in which it has pre-existed. Plato’s theory of the soul is full of Pythagorean influences: previous existence removed from the body, the doctrine of reincarnation, the need to purify the soul through knowledge and practice of virtue, the immortality and immateriality of the soul, and so on.
- b) The body is material and mortal. The body is the prison of the soul, a constant source of appetites and desires. The body leans to possession, ambition, and war. It drags the soul to the senses, where you will never find virtue or knowledge. The body is an obstacle to the knowledge of the truth that the soul must overcome if it wishes to move towards the intelligible, where it will find knowledge and virtue.