What Was Thomas Aquinas Epistemology?


Martha Robinson

Thomas Aquinas was a prominent philosopher and theologian of the medieval period whose works have had a profound impact on Western thought. His epistemology, or theory of knowledge, is a central aspect of his philosophical system. In this article, we’ll explore what Thomas Aquinas’ epistemology was and how it influenced his understanding of the world.


Thomas Aquinas was born in Italy in 1225 and lived until 1274. He entered the Dominican order at an early age and went on to become a prolific writer and scholar. His most famous work is the Summa Theologica, a comprehensive guide to Catholic theology that covers topics ranging from God’s existence to ethics.

What is Epistemology?

Epistemology is the branch of philosophy that deals with the nature of knowledge and belief. It asks questions like: What can we know?

How do we know it? What counts as evidence for our beliefs?

Aquinas’ Epistemology

Aquinas believed that there were two primary sources of knowledge: reason and revelation. Reason, according to Aquinas, is our natural ability to understand things through observation, intuition, and deduction. Revelation, on the other hand, comes from God through divine revelation such as scripture or religious experience.

Aquinas argued that reason alone cannot provide us with certain knowledge about God or other spiritual matters. Instead, we need revelation to supplement our natural abilities. However, he also believed that reason could help us understand and interpret revelation more accurately.

The Role of Sense Perception

Aquinas also recognized the important role that sense perception plays in our acquisition of knowledge. He believed that we learn about the world around us through our senses but that these senses are fallible and subject to error.

For example, he argued that we might see a stick appear bent when it is partially submerged in water, but we can use reason to correct this perception and understand that the stick is actually straight.

The Limits of Reason

Despite his emphasis on reason, Aquinas recognized that there are limits to what we can know through our natural abilities. He believed that human reason is finite and that we cannot fully understand things like God’s nature or the mysteries of the universe.

Instead, he argued that we must rely on faith to fill in the gaps in our knowledge. Faith, for Aquinas, is a form of knowledge that comes from God and allows us to understand things beyond our natural ability.


In conclusion, Thomas Aquinas’ epistemology was a complex and nuanced theory of knowledge that relied on both reason and revelation. He recognized the important role that sense perception plays in our acquisition of knowledge but also acknowledged the limits of human reason.

His understanding of epistemology has had a lasting impact on Western philosophy and continues to be studied by scholars today.