Plato’s Theory of Forms: Soul, Knowledge, and the Good
Plato’s Theory of Forms: The Idea of the Good
The Idea of the Good is supreme: it holds all other ideas. It is their foundation, their truth, and their knowability. Thanks to the Good, ideas *are* ideas, and they can be known. The Good gives the ideas their truth, that is, their being and essence. The Idea of the Good guarantees that ideas *are* ideas; ideas participate in the Good, which is their model. The Idea of the Good is the ultimate purpose to which all ideas aspire.
The Idea of the Good provides intelligibility. If an idea gets its ‘ideaness’ from a higher Idea of the Good, then this provides the opportunity for it to be known. Knowing something is knowing its foundation. Knowledge of ideas is possible because our soul is prepared to represent the ideas intellectually, because it is also of a spiritual nature. Plato states that the Idea of the Good provides the power to know what is known. The soul can know because these ideas have a beginning; the Idea of the Good ensures their knowledge.
However, Plato himself was aware that knowledge of the Idea of the Good is problematic. Knowledge is subject to a cause, and the truth of science is knowledge of causes. Accordingly, knowledge has an object that is above science. This object is an idea, but this is still above the Idea of the Good in dignity and power. Thus, the Idea of the Good becomes somewhat mysterious. Plato, in his time, could only think doctrinally through symbols, like the sun in the Myth of the Cave.
The Soul and Ideas in Plato’s Philosophy
Plato asserts the existence of the soul and endows it with features beyond being the vital principle. He tells us the soul is immortal, transmigrates to other bodies, and is also the beginning of knowledge.
In the *Republic*, Plato presents the soul as having a tripartite nature, with one soul performing three different functions:
- Rational Soul: Deals with reason, feelings, and passions. It directs and controls human activity and dominates the ruling class.
- Irascible Soul: Responsible for noble feelings and is characteristic of warriors.
- Concupiscent Soul: Predominant in the artisan class, possessed by most of the population.
Finally, in the *Timaeus*, Plato describes individual souls. The rational part is located in the brain, the irascible part in the chest, and the concupiscent part in the abdomen.
The soul, with its rational part, can know ideas because it already possesses them at birth. The soul had an existence prior to its union with the body, where it encountered the ideas. When in contact with material reality, our soul remembers (anamnesis) these ideas. We know the ideas from experience, but because the ideas pre-exist in us, we remember them upon seeing material things. To know is to recall.
To educate the soul is to help it know the ideas, not by discovering what it does not know, but by remembering what it already knows through media and dialogue. It is a process of discovering relationships between ideas within us, starting from the simplest and reaching the most general of all: Beauty, Justice, and Good.
In the Myth of the Cave, Plato calls this process “accustoming the eyes to the light.” It is a gradual process, from darkness to light, in which the soul is initially perplexed and confused. But the soul can ascend from darkness to light because it is of the nature of light. Thus, Platonic ideas are clear, and material things are dark. Between them, there is an ontological abyss only surmountable through the education of the soul, a slow and painful process of ascension to the light.