Plato’s Philosophy of the Soul and Knowledge
The Soul
Plato’s Dual Interpretation of the Soul
Plato primarily interprets the soul in two ways: as the enabler of vital activities in beings, and, specifically in humans, as a divine and immortal principle enabling knowledge and the good life. Through science, we achieve this good life and perform good deeds. The soul, in its highest form, connects us to the divine and grants us an immortal destiny.
The Term “Similarly”
In most instances, “similarly” adds no semantic value and is equivalent to “in the same way.” This is likely the case in Book VI, 507b of The Republic. Alternatively, though perhaps forced, it could refer to an analogy of proportionality, which requires four terms. For example, in Book VI, the intelligible world is to the sensible world as knowledge is to opinion. Another analogy could be: Ideas are to the intelligible world as sensible things are to the sensible world. Similar analogies appear in Plato’s allegory of the line, illustrating different degrees of being and knowing.
Science (Episteme)
Perfect Knowledge Based on the World of Ideas
Plato distinguishes two primary forms of knowledge: episteme (science) and doxa (opinion). Science is further divided into strict science (nous, dialectic, or philosophy) and discursive thought. Plato’s concept of science differs from the modern one. For Plato, science was the strict, universal, and necessary knowledge of the absolute and eternal, identified with the Ideas, achieved through reason. Modern mathematics aligns closely with this view. However, many fields considered scientific today, like sociology, psychology, and economics, would be mere opinion for Plato, based on speculation or empirical generalizations. Theoretical physics, being mathematical and rational, falls somewhere between opinion and science.
The Cognoscible
The cognoscible is that which can be known. Ideas are cognoscible because they reflect the truth emanating from the Idea of the Good.
The Allegory of the Cave and the Dialectic
Things Above
In the allegory of the cave, “things above” refer to the world outside the cave. Plato’s symbolic language points to the Ideas as the meaning of this expression.
Dialectic
Dialectic, or strict science/philosophy/nous, is the purely rational knowledge of the essential relations between Ideas, particularly the Idea of the Good. It is Plato’s method for accessing the World of Ideas. Dialectic, as a rational approach, is synonymous with philosophy and science.
Characteristics of Dialectic
- A cognitive activity exercising reason.
- Aimed at understanding the intelligible world and the relationships between Ideas.
- Ultimately seeks knowledge of the Idea of the Good as the foundation of reality.
- Defined as an “ascent to being.”
- Strictly rational, not based on perception.
- Yields strict, universal, and necessary knowledge.
- Rejects unchallenged premises, seeking the ultimate meaning and deeper reason.
The Forms (Ideas)
“Itself”
Expressions like “Beauty itself,” “Justice itself,” or “Truth itself” indicate that Plato refers not to specific instances of beauty, justice, or truth, but to the Ideas themselves. In Platonic philosophy, Ideas are the essences of things, separate from them and residing in the World of Ideas.
Episteme
True Knowledge
Episteme, meaning “to know” or “knowledge,” is often translated as “science.” Greek philosophers used it to denote true knowledge, contrasted with apparent knowledge or reasonable belief. For Plato, episteme is the true knowledge of the immutable reality of Ideas, opposed to doxa (opinion), which is knowledge of the sensible world. Aristotle, however, viewed episteme as knowledge gained through demonstration.