St. Thomas Aquinas is a central figure in medieval philosophy and theology, whose work continues to influence philosophical thought even today. Aquinas’ philosophy is rooted in the belief that truth is found in God. For Aquinas truth exists as an equation of thought and thing, and it is a comparison between the intellect and reality. This is a cornerstone of his philosophy, which is often referred to as ‘correspondence theory of truth.’ Where the appetite tends toward the Good (Example: hunger–>food–>fulfillment), the intellect tends toward the True.
Like St. Augustine, Aquinas believed that truth is universal and unchanging, as the nature of God is universal and unchanging. He argued that truth is objective and independent of human understanding or perception. This is a stark contrast to the subjective view of truth, which suggests that truth can vary from person to person.
In his ‘Summa Theologica,’ Aquinas further elaborates on his philosophy of truth. He states that truth resides in the intellect’s conformity with reality. In other words, when our understanding aligns with the actual state of affairs, we are in possession of Truth.
Aquinas also distinguished between ‘ontological truth’ and ‘logical truth.’ Ontological truth, according to Aquinas, is the truth of things in themselves. It’s the correspondence of a thing to the idea of it in the mind of God. In other words, a thing is true insofar as it exists and fulfills the purpose for which it was created by God. To give you an example, example, a tree is ontologically true when it grows, produces leaves, and fulfills its purpose in the ecosystem.
Logical truth, according to Aquinas, is the truth of propositions or statements. It is the correspondence of the mind’s understanding to the way things actually are. For example, the statement “the sky is blue” is logically true if the sky is indeed blue. So things can be True (or, as I say, a thing is A TRUTH), and claims can be True. But the logical truth is depending on the ontological truth. That is, our statements or propositions about the world can only be true if they accurately reflect the ontological truth of the things they describe. Example: “I am a man” is true. It coincides with the reality of my physical existence. “I am a man, that can also menstruate” is necessarily false. The logical claim does not coincide with the ontological claim.
Moreover, Aquinas held that God is the ultimate source of all truth. He argued that all truths are dependent on the first truth, or “first principal” which is God. This is because God’s essence is his existence, and he is the necessary being upon which all other beings depend. God is not a supreme being. He is being, itself. And the being of all other things rely on his being.
Aquinas’ philosophy on truth is deeply intertwined with his theology. He believed that through reason and faith, humans can come to know the truth. While reason can help us understand the natural world, faith is necessary to understand the divine truths that are beyond our intellectual grasp.
In conclusion, Thomas Aquinas’ philosophy on truth is rich and complex and deeply rooted in his belief in God as the ultimate source of truth. His thought continues to be influential in philosophical and theological discussions, offering a timeless perspective on the nature of truth.