St. Thomas Aquinas: Substantial Unity and Epistemology

Thomistic Conceptions of Man and Knowledge

10. The Thomistic Conception of Man as Substantial Unity

The Thomistic conception of man is central to the anthropology of St. Thomas, focusing specifically on the distinction between body and soul. Thomistic anthropology adopts the Aristotelian view, insisting that the substantial unity of man is defined by the soul being the form of the body. This conception, known as hylemorphism, required Thomas to defend the soul's capacity for self-subsistence and immortality.

From this conception of man as a unity of substance, the body is not a prison for the soul, but rather its natural destination.

11. What is Abstraction?

Regarding the ways humans access knowledge, the Thomistic position is very similar to the Aristotelian one. Knowledge necessarily begins in the senses, and there can be no direct knowledge of abstract truths.

The essences or definitions of things are obtained through a process of abstraction by the intellect. This process captures the essence of a substance so that it can be understood, regardless of its specific and unique aspects.

12. Difference Between Natural Law and Eternal Law

In ethics, Aquinas adopts a position incorporating elements from both Aristotle and Plato. The initial approach is Aristotelian: everything tends toward an end, and everything tends toward its well-being.

For St. Thomas, the good that brings happiness is a contemplative activity of the soul. Happiness is something that can only be achieved through the grace of God, leading to glory.

According to Thomas:

• The morally right action can only be that which coincides with what God commands. These precepts constitute the eternal law.
• The natural law is the realization of the eternal law within humans. This law directs us to do good and avoid evil.

13. What is Positive Law?

In politics, Aquinas states that society is natural to humans, and therefore so is the need for social organization and government. Thomism granted some autonomy to the political sphere.

The natural condition of a person justifies the need for social organization and its principles. When these principles are realized into specific rules, we engage in what is called positive law.