Saint Thomas Aquinas (1225-1274) was a theologian, philosopher and doctor of the Church, whose work remains a fundamental pillar in Catholic teaching. Known for his ability to integrate Aristotelian philosophy with Christian doctrine, Thomas Aquinas left a legacy that continues to influence the Church, philosophy and contemporary ethics. His best-known work, Summa Theologica, is a monumental work that covers the understanding of faith, morality, human nature and the relationship with God. In it, the theologian sets forth an orderly system of principles that underpin Christian doctrine, using human reason to clarify the mysteries of faith.
The compatibility between faith and reason
One of the most outstanding teachings of Saint Thomas is his firm conviction that faith and reason are not opposed, but rather two complementary paths to the truth. For Thomas, both come from God, so they cannot be in conflict. Human reason, in seeking the truth, can come to understand certain aspects of the existence of God, while faith illuminates that which cannot be reached by reason alone. Thus, the Thomistic philosopher promoted a synthesis between Christian teachings and the philosophical knowledge of the time, based on reason to explain and understand divine revelation.
The five ways to demonstrate the existence of God
In his work Summa Theologica, Thomas Aquinas presents five arguments, known as the “Five Ways”, to demonstrate the existence of God. These proofs are based on the observation of the natural world and logic. The five ways are:
- The way of motion: Thomas argues that everything that moves must be moved by something, and this motion must begin in a first mover not moved by anything else. This first mover is God.
- The way of efficient cause: Everything in the universe has a cause, and there cannot be an infinite chain of causes. There must be a first cause, not caused by anything, which is God.
- The way of contingency: If everything in the universe is contingent, that is, it depends on something else to exist, there must be something necessary that does not depend on anything else to exist, and this necessary being is God.
- The way of degrees of perfection: Thomas argues that if there are degrees of perfection in creatures, there must be a supreme being who is the maximum of all perfection, and that being is God.
- The way of design: The order and purpose observed in the universe point to an intelligent being who designed it, and that being is God.
The Ethics of Natural Law
Another key aspect of St. Thomas’s thought is his teaching on morality, which is centered on natural law. According to him, fundamental moral principles are accessible to human reason, independently of divine revelation. Natural law is a reflection of God’s eternal law, and can be discovered by observing human nature and the fundamental principles of reason. This means that all human beings, regardless of their faith, have a moral conscience that allows them to distinguish right from wrong. Thomas Aquinas considers that living according to natural law is living according to God’s will and achieving true happiness.
Some of his most notable quotes
The profound thought of St. Thomas is also reflected in his quotes, which continue to be quoted and studied today. Some of the most notable include:
- “Love leads to happiness. Only those who have it are promised eternal bliss. And without it, everything else is insufficient.” This quote highlights the importance of love in Christian life, as the path to true happiness.
- “Faith concerns things that are not seen, and hope concerns things that are not within reach.” This reflection underlines the essential role of faith and hope in the life of a Christian, virtues that allow us to look beyond what is visible and tangible.
- “The scholar is the one who leads others to what he has understood: the truth.” Saint Thomas deeply valued study and the transmission of knowledge, considering that true knowledge must be shared with others for their good.
Saint Thomas Aquinas, with his philosophical and theological thought, contributed to forging a deep understanding of the Christian faith that continues to guide believers. His teachings on the relationship between faith and reason, his ethics based on natural law, and his demonstrations of the existence of God continue to be fundamental to Catholic theology and philosophy. His work and words continue to be a source of inspiration for all those who seek a greater understanding of truth, morality, and the relationship with God.
