Last year, the Academy addressed the philosophy of St. Thomas Aquinas on the 750th anniversary of his death.

This is not an esoteric subject. Aquinas taught that all rational persons are capable of discerning right from wrong and good from evil by the exercise of free will and human reason, and they do not need the government to aid them in this endeavor.

This is generally known as Natural Law. My presentation was on the concept of natural rights, a derivation of Natural Law.

The Vatican, which is a fraction of the size of Central Park in New York City, has a fine guest house on the grounds, called The Domus, which was my home for four days. It was also the permanent residence of Pope Francis.

My 24 colleagues and I were dining in the small Domus dining room on our first day there, when the Pope came in and sat two tables away from us. It was surreal.

Here is the backstory.

How do we know what we know?

Aquinas set about to answer that intriguing question. How do we know that we exist, that 2 plus 2 equals 4, that the sun rises in the east and sets in the west, that the shortest distance between two points is a straight line? These are truisms; thus, they cannot change and all rational people can discern them. They are true intrinsically, whether we believe they are or not. 

Aquinas taught that all rational adults can discover the truth by the exercise of free will. That exercise requires rational thinking. At the time he taught this, it was radical, as other scholars taught that forces outside of us drew us to discover truths.

Let's say you like chocolate ice cream. Aquinas taught that you can rationally choose chocolate whenever you have an ice cream choice to make. Others taught that you really didn't choose chocolate; it chose you — meaning that you can't control your tastebuds.