Final answer:
A. Faith and reason
Thomas Aquinas harmonized the forces of faith and reason, demonstrating their complementarity in the understanding of Christian beliefs and the moral philosophy that underpins his ethical naturalism.
Step-by-step explanation:
Thomas Aquinas brought into harmony the two forces-in-conflict of faith and reason. In his work, Aquinas aimed to demonstrate that faith and philosophical reasoning are not mutually exclusive but can complement each other.
This reconciliation relies on the understanding that reason can be used to interpret and defend the key beliefs of the Christian tradition, while faith encompasses the spiritual truths that are beyond the full grasp of human reason. Hence, the correct answer to the question is A. Faith and reason.
Aquinas's view, influenced by Aristotelian philosophy but adapted to Christian theology, proposed that natural laws, a concept borrowed from Aristotle, were given order by divine providence. He suggested that natural law theory and divine law can guide human behavior and ethics, as well as lead to the well-being of individuals and society.
While bridging the gap between faith and reason, Aquinas also addressed the issues surrounding the nature of evil and the debate between supernaturalism and naturalism, contextualizing it within his moral philosophy.