Plato’s Philosophy: Ideas, Soul, and the Just State
Plato’s Core Philosophical Concepts
Disappointment with the political situation in Athens and the death of Socrates marked the beginning of Platonic philosophy. On one hand, contact with the Pythagoreans made Plato aware of the importance of mathematics and familiarized him with the doctrine of the immortality of the soul and reincarnation. On the other hand, his disillusionment with the dictatorship of the Thirty Tyrants, and later the Athenian democracy, led him to propose a model of society where justice prevails.
Plato blamed the Sophists for the decline of Athens: their relativism accepted no fixed rules and reduced morality to what was convenient at each moment. Following the steps of Socrates, Plato sought universal standards and immutable principles that could ensure coexistence. This led him to develop his Theory of Ideas.
The Theory of Forms (Ideas)
In this theory, Plato affirms the absolute and independent existence of certain immaterial entities, which are immutable and universal – the authentic reality. These Ideas (or Forms) constitute a perfect, eternal, and immutable world, which is hierarchical. At its apex is the Idea of the Good, which is the cause and end of all other Ideas. Hence, knowledge of the Good, achieved through reason, allows one to appreciate the order of things. The sensible world, the world we perceive with our senses, is shaped by a divine craftsman, the Demiurge, who attempts to imitate the world of Ideas. Although the material nature of the sensible world prevents perfection from being reached, the rationality found within the physical world is due to its imitation of the intelligible world of Ideas.
Knowledge: Opinion vs. Science
According to Plato, man is composed of body and soul. The soul, which is immortal, belongs to the world of Ideas, to which it returns when the body dies. While it resides in the world of Ideas, the soul knows everything that exists. However, upon incarnating in a body, it forgets what it knows. Nevertheless, contact with physical realities in the sensible world triggers a process of remembering – this is the doctrine of reminiscence (anamnesis). Learning, therefore, is recollection.
Plato distinguishes two main levels of cognition:
- Opinion (Doxa): Knowledge that is not strict, but rather a form of belief, more or less widespread, but lacking a solid foundation. It pertains to the sensible world.
- Science (Episteme): True knowledge, which pertains to the intelligible world of Ideas. There are two degrees within science:
- Mathematical knowledge: Uses sensible objects (like diagrams) as aids to reach conclusions but deals with abstract entities.
- Dialectic: The highest form of knowledge, achieved purely through reason, leading to the understanding of the Ideas themselves, culminating in the Idea of the Good.
The Dual Nature of Man: Body and Soul
The Theory of Ideas is also the basis of the Platonic conception of the human being. Man is a composite of body and soul. The soul, belonging to the world of Ideas, is considered more valuable than the body. The body is often described as a prison for the soul, and death is seen as a liberation, allowing the soul to return to the intelligible realm.
Plato describes the soul as having three parts:
- Appetitive part (epithymetikon): Related to basic desires and needs (food, drink, sex). Located in the abdomen.
- Spirited part (thymoeides): The source of noble passions like courage, anger, and ambition. Works with reason. Located in the chest.
- Rational part (logistikon): The highest part, responsible for intellectual life, reasoning, and the governance of our lives. Located in the head. This part is immortal.
Thus, the soul must use its rational part to control the spirited part (will) and the appetitive part. If not, man falls into recklessness or abandon.
Justice in Ethics and Politics
Through the rational soul, knowledge is acquired, and passions are controlled. Learning and achieving happiness are the ultimate goals for humans. For knowledge and happiness to be possible, human beings must achieve balance within their souls. This harmony is achieved when each part of the soul performs its proper function: reason rules, spirit enforces reason’s decisions, and appetite obeys.
The harmony between the parts of the soul, under the dominance of the rational soul, grants the individual justice (dikaiosyne), which is the supreme moral state or virtue. This idea of balance extends to the state (polis). Man can only attain true fulfillment and happiness within a just society. The ideal state must be structured to achieve justice.
The ideal state is one in which each citizen performs the function for which they are most capable. In the Platonic utopia, society is divided into three classes corresponding to the parts of the soul:
- Producers (Craftsmen, Farmers): Corresponding to the appetitive soul, their virtue is temperance.
- Auxiliaries (Warriors): Corresponding to the spirited soul, their virtue is courage.
- Guardians (Rulers/Philosopher-Kings): Corresponding to the rational soul, their virtue is wisdom.
Justice in the state prevails when each class performs its function appropriately and does not interfere with the others. It is the wise, the philosopher-kings, who possess knowledge of the Good, who must govern.