The One: The central concept of Neoplatonism

The One (ἡ ἁν or τὸ ἕν, spelled as hen or to hen in Greek) is the central concept in Neoplatonism, developed primarily by Plotinus in his seminal work, The Enneads. It conceptually represents the ultimate source and principle of all existence, transcending all categories of being, thought, and description. As an ineffable and absolute unity, the One is beyond duality and distinction, existing as the foundational reality from which all things emanate.

The One, interpreted by DALL•E.

Plotinus and the philosophy of The One

In Plotinus’s metaphysics, the One occupies the highest position in the hierarchy of reality. It is described as the source of all being, yet it is itself beyond being (“beyond essence”, or epekeina tēs ousias), emphasizing its ineffable and transcendent nature. Unlike other entities, the One is not composed of parts or properties; it is pure simplicity and unity.

Emanation and the structure of reality

Plotinus introduces the concept of emanation to explain the relationship between the One and the multiplicity of the cosmos. Instead of creating the world in a deliberate act, the One overflows, producing successive levels of reality:

1. Nous (divine intellect): The first emanation, representing the realm of pure thought and the archetypal Forms. It is the closest reflection of the One, containing the principles of order and intelligibility.
2. Psyche (World Soul): The second emanation, bridging the intelligible and the material realms. It governs the cosmos and enables individual souls to connect with higher realities.
3. Material World: The lowest level of reality, characterized by imperfection and multiplicity. It reflects the diminishing influence of the One as it becomes increasingly distant from the source.

The ineffable nature of The One

Plotinus repeatedly emphasizes that the One is beyond comprehension and description. Human language and concepts, bound by duality and limitation, cannot fully capture its essence. This apophatic approach — describing the One by what it is not — highlights its transcendence:

• The One is not a being, as it transcends being itself.
• The One has no attributes or qualities.
• The One is not subject to time, space, or change.

Unity and simplicity

The unity of the One is absolute and indivisible. Unlike other entities, which are composed of parts or defined by relationships, the One is pure unity. This simplicity makes it the source of all diversity and complexity, as it underlies and precedes all differentiation.

Mystical ascent and the return to The One

A key aspect of Plotinus’s philosophy is the soul’s journey back to the One, which represents the ultimate goal of human existence and the culmination of spiritual striving. This mystical ascent is a transformative process that unfolds through three primary stages:

1. Contemplation: The soul turns inward to recognize its divine origin and its connection to the higher realms of reality. This inward focus enables the individual to access the realm of Nous, where pure thought and the archetypal Forms reside.
2. Purification: To ascend toward the One, the soul must detach from the distractions and desires of the material world. This involves not only ethical refinement — living a virtuous life — but also cultivating intellectual and spiritual discipline. Purification aligns the soul with the order and harmony emanating from the higher realms.
3. Union with the One: At the pinnacle of the ascent, the soul transcends all distinctions and multiplicities, entering a state of ecstatic unity with the One. This union is beyond intellectual comprehension and sensory perception, representing a profound experience of simplicity, unity, and transcendence. Plotinus describes this moment as the soul’s true homecoming, an experience of complete fulfillment and the realization of its ultimate purpose.

Influence on later thought

The concept of the One has profoundly influenced philosophical, religious, and mystical traditions, shaping diverse perspectives on the nature of ultimate reality and its relation to the human soul.

Early Christian theology

Early Christian theologians, such as Augustine, integrated Neoplatonic ideas into their understanding of God. Drawing upon the One, they emphasized divine simplicity — the idea that God is not composed of parts — and transcendence, affirming that God exists beyond human comprehension. Augustine, in particular, adapted the Neoplatonic framework to articulate the Christian doctrine of creation, viewing God as the source from which all being emanates, though modified to fit the idea of creation ex nihilo (out of nothing).

Islamic philosophy

Neoplatonic thought, including the concept of the One, was transmitted to Islamic philosophers through translations of Plotinus and his followers. Thinkers like Al-Farabi, Avicenna, and Suhrawardi integrated these ideas into Islamic theology, emphasizing the unity (tawhid) and transcendence of Allah. Avicenna, for example, built upon the Neoplatonic hierarchy of being to explain the relationship between God (The Necessary Being) and creation, describing an emanative process that aligns closely with Plotinian metaphysics while remaining faithful to Islamic monotheism.

Medieval and Renaissance mysticism

The mystical aspects of the One inspired both medieval Christian mystics and Renaissance philosophers. Meister Eckhart, for instance, explored the soul’s union with God, drawing parallels with the Neoplatonic ascent to the One. His writings emphasize the ineffability of divine union and the ultimate dissolution of individuality in the presence of the divine. During the Renaissance, Marsilio Ficino revived Neoplatonism as a framework for understanding the cosmos and the human soul’s spiritual journey. Ficino’s work linked classical philosophy with Christian theology, emphasizing the unity and harmony of all existence as reflections of the One.

Through these traditions, the One has served as a foundational concept for exploring the relationship between the finite and the infinite, the material and the spiritual, and the individual and the universal. Its enduring legacy continues to inspire philosophical, theological, and mystical explorations of existence and transcendence.

Conclusion

The One is a cornerstone of Western metaphysical thought, symbolizing the ultimate unity and transcendence underlying all existence. In Neoplatonism, it serves as the foundation from which all being emanates, embodying the principle of absolute simplicity and self-sufficiency. Its influence extends beyond philosophy into major religious traditions, such as Christianity, Islam, and Scholasticism. In Christian theology, the One inspired the doctrine of divine simplicity and influenced thinkers like Augustine, who adapted its framework to describe God’s ineffable nature and role as the creator. In Islamic philosophy, figures like Avicenna integrated the concept into discussions of divine unity (tawhid) and cosmology, linking Neoplatonic emanation to monotheistic principles. Scholasticism further engaged with the One through its metaphysical investigations into the nature of existence and causality, particularly in the works of Aquinas.

Th legacy of the One lies in its profound intellectual impact as a unifying principle in metaphysics, providing a systematic framework for understanding the source and hierarchy of existence and shaping major traditions in philosophy and theology.

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