Epistemology is the study of knowledge, of how we know things. It deals with the nature of knowledge, what knowledge is. And it deals with the extent of knowledge, how much can we know, or do we know.
How We Know
The science before science is philosophy.
Science emerged from empiricism, and is closely related to positivism. Today the philosophy of science sits in judgment of what science is or should be, for instance, that it should be grounded in empirical evidence and use the scientific method to test hypotheses that can be proven false.
Scientism is the fallacy that measures all knowledge by its consistency with science. It is self-annihilating. The view that only scientific claims are meaningful is not itself based on science. It excludes metaphysics, religion, and ethics, leaving it very narrow for a proposition that claims universal application.
Advocates for scientism argue that the boundaries of science should be expanded into these fields. Their argument is, if we expand the boundaries of science so that it includes everything, then everything will be scientific. The problem becomes visible by applying specifics: “If we call rat poison a health food, we will be able to safely consume it.”
Aristotle’s Prime Mover
Aristotle’s prime mover sits at the top of an efficient causal hierarchy governing all motion and change in the universe. Aristotle’s first mover is a simple, unchanging form that still causally affects other beings: in Aristotle’s case the heavenly spheres would move themselves in imitation of the divine perfection, resulting in the motions of terrestrial beings. Aristotle’s god is still considered ontologically finite by theistic standards and remains only a cosmic mover rather than a creator ex nihilo. The Platonic notion of a supreme perfection at a remove from all things and Aristotle’s causally efficacious, disembodied mind would combine to suggest a powerful model for Western theologians seeking language to describe God’s nature.
When St. Thomas considers the question, Whether God is altogether simple, he quotes St. Augustine, “God is truly and absolutely simple.” St. Thomas then goes on to affirm that, “The absolute simplicity of God can be shown in many ways.” This is the teaching of the Catholic Church § 202.
We firmly believe and confess without reservation that there is only one true God, eternal infinite (immensus) and unchangeable, incomprehensible, almighty and ineffable, the Father and the Son and the Holy Spirit; three persons indeed, but one essence, substance or nature entirely simple.
“God created man in his own image, in the image of God he created him; male and female he created them” Gen 1:27. St. Augustine, at the beginning of his Confessions, declares, “You have formed us for yourself, and our hearts are restless till they find rest in you.”
We’ve known many Catholics who, in the greatest adversity, are serene. St. John of the Cross, locked in a dark, cold, desolate cell, six feet by ten feet, beaten three times a week, experienced Rabbi Yeshua’s joy as fire and light, comes first to mind. St. John of the Cross said there are caverns ordered to God within us, into which nothing else will fit.
It has been so for a very long time. Recall Elijah’s Contest of Sacrifices, when Elijah stood alone against 450 prophets of the false god Baal. When Baal didn’t answer their cries to send one lightning strike to set fire to their bull they cried aloud and raved and hopped around and cut themselves and bled. This false craving is not a harmless process, it wounds us. But Elijah was serene. To show God’s power, he soaked his bull in water three times, and then said once, “Answer me, O Lord, answer me, that this people may know that thou, O Lord, art God, and that thou hast turned their hearts back” 1 Kings 18:37. Then God‘s fire fell on Elijah’s bull and consumed it, and the wood, and the stones, and the dust, and the water in the trench. Only the true God can answer with fire!
St. Thomas Aquinas
“We walk by faith, not by sight” 2 Cor 5:7. “Faith is the assurance of things hoped for, the conviction of things not seen” Heb 11:1. St. Thomas‘ remarkable clarity of ordered thought grounds his case firmly in the Sacred Tradition of Apostolic Teaching as taught by the Church Fathers, exposes it to the opposing arguments offered in his time, and overcomes them.
Some scholastic philosophers today say St. Thomas’ arguments are not valid. However, that does not mean we have to judge equally between them. St. Thomas is a Doctor of the Church. During more than 700 years his arguments have been studied in Catholic seminaries and universities by scholars familiar with both the pagan Aristotle and the Catholic St. Thomas, who have accepted his five arguments as valid. When we find a philosopher opposed to these arguments who has comparable stature, who thinks and writes with comparable clarity and order, and who is likely to be read 700 years from now, perhaps the case will be more balanced. For now, St. Thomas makes the more important case.
These five arguments support the existence of the one God of Israel § 199-231. As we’d expect from St. Thomas, they work as well for the Catholic faith since we understand that § 253 “The Trinity is One. We do not confess three Gods, but one God in three persons, the consubstantial Trinity.”
1. Unmoved Mover
In the world some things are in motion. Aristotle’s discussion of astronomy observed that planetary motion, which causes seasons to change, requires an unmoved mover. St. Thomas uses the same idea, everything that moves has to be moved by something else, but at the start of the chain of movers must be an unmoved mover, God.
Nothing can be the cause of itself; to do so it would have to be prior to itself, which is impossible. Also, it is not possible with causes to go on to infinity, because the first cause always causes the intermediate causes. And, to take away the cause is to take away the effect. If there is no cause, there can be no effect. The first cause is always God. (St. Thomas calls it “efficient cause,” but that distinction is not much used among philosophers today.)
Third, contingency. We find in nature things that are possible to be, and possible not to be. St. Thomas says that if everything can not-be, at one time there must have been nothing in existence, because that which does not exist begins to exist only through something already existing.
Among persons there are some more and some less good. But more and less can only exist in reference to an absolute standard, in this case an absolute standard of goodness. Since men mix good and evil impulses, there must exist an absolutely moral being, and this can only be non-human and not in the world.
St. Thomas suggests that inanimate objects, such as planets, could not have entered their orbits on their own, because they lack the intelligence to do so. But they are perfectly aligned. Since men cannot move planets, their orbits must have been designed by a being with the intelligence and power to do so.
St. Thomas’ Summa attempts to explain the origin, operation, and purpose of the entire universe and the role that everything in the universe plays in the attainment of that purpose. Physicists search constantly for a “unified field theory” or, if they venture outside the realm of fields, a “grand unified theory.”
The Summa offers a very disciplined method of organization. For each question St. Thomas considers, he begins by breaking down the question into several articles. He begins each article with several objections that have been made to it by eminent scholars and states them fairly, often more clearly than the eminent scholars themselves. Then he refutes their objections. Then he states his own view. Then he replies to each of the objections.
Here is an example, the very first question St. Thomas considers, “The nature and extent of sacred doctrine.” To see the Summa’s scope and extent, notice that it comes in five parts. Three of the parts are numbered, but the second part is divided into two parts, and he adds a supplement to the third part.
The First Part, on the one God, The Blessed Trinity, Creation, The Angels (Spirit), The Six Days (matter), and Man (Spirit and Matter) addresses 119 questions in this very comprehensive manner. The First Part of the Second Part, on Man’s Last End, Human Acts, Passions, Habits, Vice and Sin, Law, and Grace, covers 114 more questions. The Second Part of the Second Part, on Faith, Hope, Charity, Prudence, Justice, Fortitude, Temperance, and Acts Which Pertain specially to Certain Men, answers 189 more questions. The Third Part, on The Incarnation, The Life of Christ, the Sacraments in General, Baptism, Confirmation, the Holy Eucharist, and Penance, answers 90 more questions. The Supplement to the Third Part, on the remainder of Penance, Extreme Unction (Anointing of the Sick), Holy Orders, Matrimony, and the Resurrection, an additional 99 questions. Two Appendices together answer 3 final questions. 614 questions in all.
About St. Thomas
St. Thomas was born Tommaso d’Aquino. “Aquinas” is from the county of Aquino in the Kingdom of Sicily, an area where his family held land until 1137.
Since there have been so many “St. Thomases” during the Church’s 2,000 years, we call the most prominent one St. Thomas Aquinas. It means, “St. Thomas from the county of Aquino.” It is not his last name.