First Cause: Metaphysical and Philosophical Definition

The term First Cause designates the ultimate cause upon which every chain of causes and effects depends. In metaphysics, it is the first principle of being, order, and intelligibility. The notion of the First Cause does not necessarily refer to the first cause in time, but rather to that without which no causality would be possible.

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Reflection on the First Cause arises from the observation of the world. Things appear to be linked to one another through relations of causality: certain events produce other events, certain beings depend upon other beings, and certain realities explain others. The metaphysical question is therefore whether this series of causes can be self-sufficient or whether it requires an ultimate foundation.

Aristotle was the first to formulate this question systematically. In his search for principles, he shows that every explanation presupposes a starting point. He argues that if one removes the cause, one also removes the effect, and above all that one cannot proceed indefinitely through causes without making explanation itself impossible. In the Metaphysics, he writes: “If there is no first term, there is no cause at all” (Metaphysics, II, 2, 994a1–2). The First Cause thus appears as a requirement of intelligibility itself.

For Aristotle, this First Cause is the Unmoved Mover. Everything that is moved is moved by something else; yet an infinite regress of movers would never explain the actual motion of the world. One must therefore admit a principle that moves without itself being moved: pure actuality and the ultimate source of all motion.

Classical metaphysics takes up and deepens this analysis. The First Cause is not merely the first term in a series; it is that upon which the very existence of secondary causes depends at every moment. It grounds their causal power and enables them to act according to their nature.

St. Thomas Aquinas carefully distinguishes the First Cause from secondary causes. Secondary causes are the natural, physical, or created causes that produce effects within the world. They are real and effective. Yet they act only by virtue of a being and a power that they have received. The First Cause therefore does not eliminate secondary causes; it makes them possible.

This distinction avoids two opposite errors. On the one hand, deism tends to conceive God as an initial cause that has abandoned the world to itself. On the other hand, occasionalism denies the genuine causality of creatures. Classical doctrine affirms instead that God acts through secondary causes without abolishing them.

Nor should the First Cause be understood as a mere initial event located at the beginning of time. Even if the universe had always existed, the question of the First Cause would remain. It concerns the ontological dependence of beings and not merely their chronological origin.

The notion of the First Cause is closely related to that of contingency. Contingent beings do not contain within themselves the reason for their existence. They point beyond themselves to a cause that possesses being in a non-received and non-derived manner. The First Cause thus appears as the Necessary Being upon which every contingent being depends.

This perspective leads to the identification of the First Cause with God. Yet God is not merely the first cause in the sense of a beginning; He is the permanent cause of the existence of all things. According to St. Thomas, creating and conserving in being belong to the same divine act. Creatures therefore depend continually upon the First Cause in order to exist.

The doctrine of the First Cause also illuminates the relationship between creation and participation. Created beings exist because they participate in the being communicated to them. Their very power to act likewise participates in the primary causality. Every created causality thus appears as a limited participation in the causality of the Principle.

From a symbolic perspective, the First Cause remains invisible in its effects while manifesting itself indirectly through them. Beings reveal not only their own nature but also testify to the source from which they proceed. The cosmos thus becomes intelligible as an order of signs referring to its causal principle.

Jean Borella emphasizes that metaphysical knowledge consists precisely in ascending from what is manifested to its principle. Causality is not merely an explanatory mechanism; it is also a path of knowledge leading from visible effects to the invisible cause that grounds them.

Modern thought has often reduced causality to a relation between observable phenomena. Metaphysics reminds us, however, that the ultimate question is not merely, “How do things act?” but also, “Why are there causes rather than nothing at all?” The notion of the First Cause addresses this fundamental question.

The First Cause thus appears as the ultimate foundation of all intelligibility. It makes it possible to understand why the world exists, why it is ordered, and why secondary causes possess genuine efficacy. It is the principle to which every search for causes ultimately leads and one of the central concepts of metaphysics.

See also: Cause, Creation, Contingency, Being, Necessity, Participation, Principle, Theophany.

First Cause

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Further Reading

See also:

Cause

Contingency

Creation

Finality