Plato’s Philosophy: Ideas, Soul, and the Pursuit of Truth
Plato’s Enduring Influence on Western Thought
After Socrates died, Plato’s influence grew. The situation reflects factors that led him to declare that only radical reform of political structures could avoid the collapse of the State. Unless government passes into the hands of philosophers, there is no end to the evils of the state and eventually of its citizens. Against the relativism and skepticism taught by the Sophists, Plato proclaims the existence of a sole and absolute truth. Education is the essential work through which people become leaders, are fair, and are directed by the state’s capacities. In Platonic thought, the moral and political spheres recover interest in topics beyond philosophy, from a completely new perspective: the sensible world is only known by means of another suprasensible world, the world of forms or ideas, which are models of physical objects. This second nature explains reality, absolute truth, and the universal.
Plato’s Life and the Academy
Plato (427-347 BC) was born in Athens. His initiation into philosophy, under the tutelage of Cratylus, taught him that all things are in steady flow. Plato traveled to southern Italy and Sicily, where he became familiar with the ideas of the mystic Orphic and Pythagorean philosophies. In Syracuse, he attempted, unsuccessfully, to influence the city’s government. Back in Athens, he founded the Academy, described as the first university. Its name comes from an ancient shrine dedicated to the mythological hero Academus. The Academy offered illustrious subjects as diverse as mathematics, astronomy, philosophy, and political theory. The organization of activities was based on the Pythagorean community model, but it had a fundamentally political purpose: to train new leaders. Plato made a second trip to Syracuse to influence the new ruler, Dionysius II, but he had no success. Returning to Athens, Plato held the directorship of the Academy and was called back to Syracuse while drafting his works. This third trip was a complete failure. Back in Athens, he dedicated himself to the writing of his last works. He died at the age of 80. The influence of Plato’s work is immense.
Plato is the first philosopher whose works are preserved in substantial numbers. Our knowledge of him is much deeper than that of his predecessors. He wrote for over 50 years, and his thoughts were constantly evolving. Thirty dialogues are presented in three blocks from three successive periods:
- First period or youth: research on moral definitions.
- Middle or maturity period: interest in metaphysical and epistemological problems.
- Last period or old age: self-criticism of his doctrines.
Plato’s Theory of Forms
The theory of ideas about reality and knowledge permeates all of Plato’s thought. It explains that things really are as they are and how we know them. We know each other through reason, not sense. According to this criterion, things are not neutral, and not all people truly know. There is a preexisting individual concept, a concept that exists by itself and forms part of the reality of concepts. Plato’s thought is dualistic, positing the existence of two worlds: the sensitive world of appearance, of material bodies under a continual process of change (the world of Heraclitus), and another eternal and immutable realm, the real world of intelligible ideas or pure, uncontaminated forms (the being of Parmenides), of which the sensitive world is an imperfect copy. This dual aspect of genuine Platonic thought concerns the participation of forms in things. Forms are expressed in or are present in diverse things. To understand the transcendental sense of ideas, we must see that they manifest in things as a clear pattern or copy. There is a concept of similarity. The ideal model is what sensitive things imperfectly imitate or reproduce. Ideas occupy a transcendental level in the world, while thoughts are the purpose or goal of material things. Thoughts are the causes of human actions and events in the natural world, including the animal and plant world and inanimate nature. The intelligible world culminates in the idea of the Good, the cause and end of the universe and the source of knowledge.
The Idea of the Good
The idea of the Good can be compared to the sun. The relationship between the sun and the visible world is analogous to that between the Good and the intelligible world. The idea of the Good is not an idea among others but is only knowledge because it is due to being. The idea of the Good, also called Beauty, illuminates both the sensible world and the world of ideas or essences and represents the final end, the reason for everything that exists. The idea of the Good allows us to understand why things are as they are, as they are always in the best way possible. Reality aspires to be like the idea of the Good. The idea of the Good is not to be associated with a creator of the universe, nor is it a god who begot the universe; rather, it gives meaning and ultimate purpose to the universe. True knowledge is the understanding of ideas; this world is not a sensitive problem that immediately arises, as we are aware as much as possible.
Reminiscence and Knowledge
The explanation is that knowledge is possessed but is unconscious; it refers to the existence of the soul in earlier life forms. When the soul incarnates, it forgets; the view of material objects awakens the record of forms. Knowledge is reminiscence. There are two types of knowledge and two types of objects of knowledge. Science or knowledge has as its object the world of intelligible ideas, while belief and opinion have as their subject the sensitive world of physical objects. The degree of truth known is proportional to the reality of what is known. The more perfect the idea or form, the more cognizant one is. Between being and non-being is human reality, which is not the same as ever because it is constantly changing. This is not the subject of true knowledge but of belief or opinion.
The Divided Line
The metaphor of the divided line allows you to view different levels of knowledge corresponding to varying degrees of being. The more real the object, the more exact the knowledge. The line is divided into two unequal segments: one representing true knowledge of the intelligible world, and the other representing views on the sensitive world. The intelligible world is divided into pure ideas and mathematical objects. The sensitive world is divided into material bodies and the image or shadow of material bodies. The relationship between originals and copies is the full relationship between the intelligible and sensible worlds. Things that are intelligible and eternal are the object of constant real knowledge, while sensitive, created, and mutable things are the object of belief. There are four degrees of knowledge, corresponding to different parts of the faculty of the soul. The lower levels are conjecture and belief. At the level of rational knowledge are discursive intelligence and pure science or dialectical knowledge. The latter type includes ideas and discusses the conceptual dialectic of philosophers trained in the supreme science. Discursive knowledge, or hypothesis-based mathematical discourse, draws conclusions from possible mathematical reasoning. There is no record of sensitive objects after nostalgic ideas have been previously seen. The assembler of pure nostalgia boosts the soul to meet the beautiful, just, and good, the relevant and original image to imitate. This is Platonic love: the longing of the soul for the eternal, ideal, and perfect; the true philosopher’s aspiration towards true and essential knowledge.
The Soul and its Immortality
The conception of the soul is connected to the divine origin theory of ideas. The soul reaches liberation when the body dies. Evidence of the soul’s immortality conveys the strong impression that it was a central tenet of Plato’s thought. In Platonic psychology, the psyche is divided into three functions: reason, desire, and the desires of the body. The recognition of intrapsychic conflicts partitions the soul, which struggles against forces operating within the individual. The soul is divided into three parts: the rational, according to knowledge; the irascible, according to will; and the concupiscible, which causes bodily desires. Paradoxically, these three parts of the soul are located in three places in the body: the rational, which is immortal, in the head; the irascible, in the thorax near the heart; and the concupiscible, in the belly, where the lowest desires reside. Plato poetically compares the soul to a chariot driven by a charioteer who governs two horses, one good and one untamed. Subordinate to ethical and political psychology, the rational soul governs and has dominion over the other two parts. The rational soul is considered divine and immortal. Anthropological dualism reappears, with the human being formed of two distinct components: reason, which is immortal and divine, and voluntary and physical appetites, related to the body. The joining of the body and soul is accidental and temporary.
The Allegory of the Cave
The myth of the cave compares human nature to the condition of prisoners in a cave. Deep in a cavern, prisoners are tied so that they can only see shadows on the wall in front of them. They mistake these shadows, and the echoes of voices, for reality. One prisoner escapes and begins the arduous climb outside. Dazzled by the external light, he can at first only see shadows or reflections in water, then things directly, and finally the sun itself. The changes often cause the visible world. The meaning of the myth is that the world previously associated with housing and the light of the prison fire is the power of the sun. If you compare the rise and contemplation of objects in the soul’s world to the intelligible world, you will not deviate from my conjecture. In the intelligible world, the idea of the Good is the ultimate reality; it is concluded to be the cause of all visible light, and in the intelligible world, it is the sovereign provider of truth and intelligence. The idea of the Good is compared to the sun: just as the sun causes vision, the Good causes understanding and intelligibility in the universe of ideas. The result is the Artificer, who constructs the chaotic material world using eternal matter as a model.