Philosophical Foundations of Human Nature: Plato to Stoicism

Platonic Dualism and the Nature of Humanity

Platonic philosophy is the philosophical starting point of the dualistic vision that pervaded for centuries the intellectual worldview and common beliefs about human nature. Plato's objective was to reach an objective and universal definition of human nature, moving from the *nomos* (convention) to the *physis* (nature). His theory was born to defend this view, also held by Socrates, against the Sophists. The Sophists defended the subjective character of human nature, arguing that there is nothing absolutely stable or real. This relativistic approach was the logical conclusion of the remarks of Herodotus about the different ways to overcome life's challenges. Plato wanted to escape ethical and physical skepticism and offer stability to the world of *nomos*. For this, it was necessary to ensure human nature was eternal and unchanging in the realm of *physis*.

The Allegory of the Cave and Knowledge

Plato presents the Allegory of the Cave to describe the situation of the human being with regard to knowledge. The initial state and the prisoners symbolize human beings and their flawed understanding of reality, believing that what they capture by the senses (those images) is true. But these are merely shadows of the true reality, which is located outside the cave. The true reality would represent the World of Ideas, and the released prisoner symbolizes the philosopher.

Aristotle: Naturalism, the Soul, and Sociability

Aristotle began the understanding of human beings from their physical studies. Aristotelian theory stems from a naturalistic perspective, rejecting Plato's dualism, for soul and body are not separate entities but **indissoluble** elements in both humans and other living things. The soul is the *form* of the body, and in its primary sense, the soul is *life*.

Furthermore, Aristotle distinguishes types of soul according to the different types of life. These include:

• The **Nutritive/Vegetative Soul** (related to basic life functions like growth and reproduction).
• The **Sensitive Soul** (related to sensation, movement, and feeling).
• The **Rational Soul** (unique to humans, enabling thought and contemplation).

Unlike Plato, who believed human nature is realized and reaches its fullness in the eternal and incorruptible life of the World of Ideas, Aristotle held that the zenith of fully human life is found in the contemplative knowledge of reality here on Earth. He also recognized **sociability** as another key element in the human constitution.

Hellenistic Philosophy: Ethics and Happiness

Epicureanism: Happiness Through Pleasure

In Epicureanism, the human being must seek their happiness and fulfillment in *pleasure*. Pleasure is basically defined as the absence of pain (*aponia* and *ataraxia*).

Stoicism: Living in Accordance with Nature

Stoicism defines the human being based on the concept of **Nature** (or *logos*).