St. Thomas Aquinas
Historians have often pointed out that European intellectual culture has two origin stories: one sees Christianity as the guiding principle of Western philosophy, and finds its roots in Jerusalem; another sees the pagan Greek philosophers as its founders, and thus roots itself in Athens. Athens and Jerusalem suggest very different outlooks on life and the universe, and make very different assumptions about what intellectual inquiry ought to look like.
Every once in a while, a figure comes along who attempts to bring Athens and Jerusalem together: someone who believes Greek philosophy and Christian faith are not only compatible, but part of a single overarching truth. One of the most influential was St. Thomas Aquinas.
Thomas Aquinas was born to a noble family sometime around 1225 AD. At age 13, he decided to join the Dominican monks and lead a life of sober, celibate prayer and scholarship. His parents were not pleased. They sent his brothers to kidnap him from the monastery and drag him back to their castle, where he was locked away in a tower. Thomas’s imprisonment did nothing to dissuade him from joining the Dominicans – even when his family hired a famous prostitute to seduce him into breaking his holy vows. The scheme failed, and ultimately his parents gave up. Thomas was allowed to leave the castle and join the monks as he wished.
Around this time, European scholars were just getting their hands on the first Latin translations of Aristotle. The great philosopher’s works had been lost for centuries during the European Dark Ages, but Muslim scholars had preserved them, both in the original Greek and in Arabic translation. They had fueled some of the most important debates in Islamic philosophy, and volumes of commentary had been written in Arabic. Thomas’s teachers were some of the first Europeans to get their hands on these works, and most of them rejected Aristotle due to his perceived incompatibility with Christian doctrine. They much preferred Plato, whose distrust of the material world seemed more congruent with a Christian conception of the spiritual.
Thomas was not convinced. He believed Aristotle was a more rational thinker than Plato, and that rationality was a powerful tool in the effort to understand God’s will. He wrote dozens of books arguing for Aristotle over Plato and trying to harmonize the Aristotelian logic with Christianity. It sparked a revolution in Christian thinking, and Thomas become one of the most celebrated Christian philosophers in history.
III. Aquinas’ Ideas
Reason, Revelation, and the Prime Mover
Today, lots of people think there’s a tension between reason and faith. If you accept something “on faith,” then no rational argument will sway you from it. We’re sometimes told that faith is the domain of religion, and that reason is out of place in the search for a relationship with God. Indeed, the tension is so deep-seated in some that they imagine it’s an eternal struggle, reaching all the way back to the origin of religion.
Aquinas would have laughed at that. For him, reason and faith were not only compatible, but mutually constructive. They answered different kinds of questions, and only by addressing both kinds of questions could we understand our place in the universe. Reason is the domain of physical reality or “nature.” You have a question about how things work? You want to know what’s out there in the universe? Use reason! Faith is no help if you want to understand the material world. And you have to understand the material world if you want to be a good Christian! After all, if your goal in life is to understand your Creator, what better place to start than with a thorough scientific understanding of Creation?
There are limits, however, to the powers of reason. Some of Thomas Aquinas’s most influential works were his arguments about where those limits might lie. One example is his argument about the Prime Mover or first cause. Reason tells us that each thing has a cause. Everything that exists is due to something that happened in the past. But those events themselves had causes, which had their own causes, and so on. Where does it end? Does the causal chain go on forever? Aquinas argued that reason could tell us there was some original uncaused cause, a Prime Mover who could somehow straddle the boundary between material reality and whatever lies beyond. We could know that there was something beyond. But we couldn’t know anything about its characteristics. Is it anything like the Christian notion of God? We simply have no way to know.
Reason can get us right up to the boundary of the material world – and no further. There is no way to get from the Prime Mover to the Christian God by reason alone. At this point, Thomas argued, we must turn to revelation, to the moments when God has revealed the spiritual world to human minds. Crucially, that spiritual world was not part of the material world – god is not a Being in the same sense that you and I are beings. Rather, God is that which transcends the boundary between material and immaterial, and whose nature can only be understood through a combination of reason and revelation.
IV. The Unknowability of God
Christians often describe the attributes of God. They’ll say He is loving, He is merciful, He is all powerful, He is indeed a He. Thomas thought this was a mistake. All we can truly know about God is that something exists at the boundaries of physical space and time, and that this something is only dimly visible to the intellect. He said that “God” was the most natural name for such a transcendent reality. But the characteristics of God are fundamentally unknowable. We can’t even say that God exists, since existence is a quality of material objects and God is beyond the material. So God does not exist, at least not in the same way that you and I and popsicles exist. But neither does God not exist, at least not in the same way that unicorns and dragons don’t.
So if you can’t say anything about God, not even that God exists, what’s the point of Christianity? Why worship a being/non-being who simultaneously exists and doesn’t exist? Thomas didn’t just throw up his hands and walk away from the concept of God altogether. Instead, he argued that we should describe God analogically, always recognizing that our descriptions are vague pointers rather than absolute truths. We might say that God exists, for example, with the clear caveat that we don’t mean he exists in the way that material objects exist. We might say that God is loving, but always bear in mind that divine love is something radically different from the love we know as human animals.
In short, God is beyond reason, and if he is beyond reason then he must be beyond language. And if God is beyond language, then statements about God can never be literally true – they can only be true in a metaphorical or analogic sense. Christianity, then, is an effort to know the unknowable by describing the indescribable. As long as we remember these limitations, reason and revelation can support each other like the twin arches of a Gothic church.
For creation is not a change, but that dependence of the created existence on the principle from which it is instituted, and thus is of the genus of relation… Creation is thus said to be a kind of change, according to the way of understanding, insofar as our intellect accepts one and the same thing as not existing before and afterwards existing.
This is an example of the “analogical” language which Aquinas thought must be used in discussing God. We can say God created the world, but it’s a mistake to think that divine creation is literally similar to physical creation. When we say God created the world, we are describing a relationship only vaguely similar to the one we mean in saying that a carpenter created a chair. The carpenter works in physical space and time. At one time, there was only a pile of wood; at a later time, there was a chair. God works beyond space and time. Creation, therefore, is not an event that takes place at a particular time or in a particular location; it’s a relationship of logical or metaphysical dependency. To say we are created by God is to say we are dependent on God as an underlying principle, or that we are at all times being created by God (though this way of phrasing it is equally wrong because it still suggests that God works within time). The language of “creation” is understandable to the human mind, but not very accurate if taken literally.
VI. In Pop Culture
Beyond the Physical Plane
Lots of sci-fi worlds play with the boundary between physical reality and what lies beyond. In some cases, the boundary is a psychological one. In 2001: A Space Odyssey, for example, humans transcend to higher and higher levels of understanding but remain firmly within the physical world. In some cases, though, the transcendence comes closer to the sort of dichotomy Aquinas believed in. You find this as one of the victory conditions Civilization IV: Final Frontier, where your space empire can build Astral Gates and pass through them to another plane of existence. Aquinas would have objected, of course, to the idea that mere technology could bridge the gap between physical and spiritual.