Final answer:
Aquinas believed that the intuition to do good and avoid evil comes from the faculty of reason. This inborn guidance, combined with rationality, helps individuals understand and practice moral principles. Virtue is actualized through practice, aligning with a potential that exists prior to action.
Step-by-step explanation:
To Thomas Aquinas, we get the intuition to do good and avoid evil from the faculty of reason. Aquinas, following Aristotle, believed that humans are rational animals and that our rational capacity is what makes us distinct. Reason allows us to deliberate and make judgments about right and wrong, operating through a moral faculty that interacts with culture and is shaped by our evolutionary history as social mammals.
This moral faculty is akin to the concept of a synderesis, an innate habit of the practical intellect that enables individuals to understand basic moral principles and inclinations. While Aquinas doesn’t explicitly call it a faculty, this concept closely resembles what we might think of as a moral faculty today. According to Aquinas, this inborn guide combines with our rational nature to assess actions, shape our desires towards the good, and refine our understanding of virtue through our actions and experiences.
Much like the development of the senses, which we possess before we use them, Aquinas believed that we begin with the potential for virtue and then actualize it through practice. This aligns with his view that to become just, temperate, or brave, one must engage in acts that are just, temperate, or brave, respectively. The exercise of reason, informed by innate moral intuitions, thus plays a central role in our deliberate choices to do good and avoid evil.