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A Haunting Proof

An Introduction to Aquinas' Fifth Way

There is something haunting about the question of meaning and purpose and significance. Is our world genuinely meaningful, we ask ourselves, or does it just look that way? Others will say, no actually the world does not look meaningful, not when you look at it closely. Instead, they might say, it is just very useful for humans to think the world is meaningful.We seem to have a hard time not asking the meaning question. It haunts us. Share on X The first group is asking about objective meaning in our world: does this world have purpose and significance detached from individuals’ experience. The second group denies objective purpose and significance but admits that humans have a subjective and existential need for the appearance of meaning. Yet what is interesting is that either way we seem to have a hard time not asking the meaning question. It haunts us. For some, it haunts us like a mystery that needs solving. For others, the haunting is more like an unwelcomed specter that disregards our disbelief and shows up anyway.

What if our haunting itself had purpose? What if our persistent need for meaning, and the way we notice purposefulness all around us, is itself a clue that points us somewhere important?

A Universe of Purpose

There is old insight that can help us. St. Thomas Aquinas gave five ways to argue for God’s existence, and the last one opens a pathway. Thomas points out something so common that it is easy to overlook. Purposefulness saturates our world. It is part of the beauty that compels us. The bee collects pollen for the hive and in the process pollenates flowers that could not survive without it. The hive numbers in the thousands, and yet they coordinate with a kind of dance to produce abundant honey. The elegance that compels us also allures us to describe the whole thing using purpose words. The bees seem to work in order that flowers might thrive and multiply and each individual bee seems to work in order that the hive might fill its role in the system. No one thinks the bee wakes up with a conscious purpose to do this. The purpose originates not in the intention of the bee but in the whole system and how the dance proceeds.

Yet it is not just the bees. The beehive is a small note in a great symphony. The cosmos seems to sing with purpose. The DNA in our cells and the black holes in our galaxies both, very differently, fulfill purposes that together make the universe beautifully coherent. It is not mere mechanism. It lacks the monotony of a machine. There is a spontaneity without chaos and an order without inevitability. The world looks like it is on purpose.

At least Thomas thought so. He used an image of an arrow shot from a bow. Imagine you see an arrow mid-flight in slow motion. You watch it move steadily forward in a precise direction: the fletching at the back stabilizing the shaft and the pointed head cutting through the air. You know that arrow has a purpose, and it comes into view when you see the arrow hit the target, just off the bullseye. It was close but you know it missed. But when you say the arrow missed, you don’t really mean that the arrow intended anything at all. No, instinctively, you know that whatever aim the arrow had originated elsewhere. The aim originated in the archer, but it was expressed in the arrow. Thomas points out that the arrow has a purpose without having the ability to do anything on purpose itself. That can happen because behind the flying arrow is the archer: someone who has intention.

Who is the Archer?

Thomas argues that if the world looks intentional, then you have to ask: what originates that purposefulness? The vast majority of the universe is unintelligent and therefore, like the arrow, unable to intend its own end. Where then is the archer? Humans are capable of intention, but not at the level that can explain the cosmos. That moves Thomas to posit a being that is intelligent and yet also capable of intending the coherence of the universe. He calls that being God.

The purposefulness we see is a clue to the God we cannot see. Put differently, there is a significance to the purposefulness we observe, and that significance is God.

The purposefulness we see is a clue to the God we cannot see. Share on X
But wait a minute, someone will say: why do we need God to explain purposefulness? Bees and flowers evolved together and mutually incentivize symbiotic adaptations. That is called natural selection, not God. It may appear to us that it is purposeful, but it might be better to call it functional. Bees and flowers, along with planets and galaxies and viruses and weather patterns, function the way they do because of natural conditions and a lot of time to work it out.

Thomas knows a lot about natural causes. In fact, he sees natural causality as a fundamental part of purposefulness. But he will refuse to concede that natural causes and God are in competition. Go back to the arrow in flight. Imagine someone argued that the real cause of the arrow was not an archer but rather the potential energy stored in a bent bow which was then transferred into the arrow as kinetic energy, resulting in the arrow’s motion. That is a puzzling argument because the affirmation of one does not require the denial of the other. Thomas does not deny natural causality. But causation is not the same as purpose. He sees a pervasive intent throughout the natural world and underneath natural causation, and then asks, what is the significance of that pervasive purpose?

This explains a difference between Thomas and what is sometimes called Intelligent Design. Intelligent Design is a school of thought that, like Thomas, looks at this world and concludes it was designed by an intelligence. It argues that some phenomena in the world could not develop as we observe them according to naturalistic mechanism. Regardless of its merits, Thomas is doing something different. Thomas is not interested in anomalies that natural causality cannot explain. He sees natural causality itself as purposeful, and therefore his argument rests on a vision of the whole system, rather than trying to explain an anomaly inside it.

Purpose: Reality or Invention?

But others will have another objection. Some will say that the purposefulness we perceive tells us less about the nature of the universe and more about human psychology. The human is a purpose-loving species, and our brains find it, or project it, wherever we can. Perhaps this helped us design tools which gave us an evolutionary advantage. The only purpose is the one locked in the human brain.

Yet again Thomas is not phased. The human brain and its development is only another natural cause in the larger cosmic system. Perhaps the human brain is wired to find purpose all around us. Perhaps that gave us an evolutionary advantage. But why does this discount the significance of the purposefulness we perceive? Our five senses give us reliable information about our environment. Why can’t our ability to perceive purposefulness give us genuine insight about how things really are?

Of course, it is possible to deny any significance to the purposefulness we perceive. We can believe that the coherence of the universe is interesting, but not meaningful. We can commit ourselves to the notion that the only meaning that exists is the meaning we create individually or as a society. That is the position of a great many people today. Yet is that any more rational than Thomas’ approach? Thomas’ view allows us to observe the world with rigor, as it is, taking full account of natural causality. His view also allows us to follow the trajectory of those observations toward an explanation that makes great sense of the data. Yes, Thomas’ view requires faith – it does not prove its conclusion in the same way that, for instance, a mathematical proof does. Yet denying significance in the universe is also an act of faith. In fact, it may take more faith to be surrounded with elegant and beautiful purposefulness, and to have a mind designed to see it, and yet still deny it.

Meaning still haunts us, even when we try to suppress it. Meaning still haunts us, even when we try to suppress it. Share on X

Beyond the Fifth Way

Thomas’ Fifth Way takes us a good distance, and yet it does not solve the mystery. It helps us take the purposefulness of our world very seriously, and gives us very good reason to see that it is all significant. God designs the purpose we perceive, and God designs our ability to perceive it. Yet if we leave it there the mystery still haunts us. Who is this God? If the purposefulness we see is a clue to the God we cannot, then that still leaves us yearning to see further toward that God, or else fearing what we may find.

Thomas’ Fifth Way leaves us haunted by that question. But the God in whom Thomas believed would not keep us there. “And the Word became flesh and dwelt among us, and we have seen his glory…” (John 1:14). We are haunted by meaning – is there a significance to the purpose we perceive? Our reason can make us see the answer is, plausibly, yes. Good as that is, it leaves us yearning, seeking, fearing.

The God who haunts us with the question of meaning, answers his own question in the unveiling of his Son. Share on X

Perhaps there is a purpose here also. The God who haunts us with the question of meaning, answers his own question in the unveiling of his Son. In Christ we find the one who animates this world with significance. He is no specter and (it turns out) he never haunted us. Rather, he is risen and he has been seeking us all along. In him we find the one through whom and for whom all things were made, and in whom all things hold together, and through whose blood all may be reconciled (Col. 1:15-20).


Image Credit: Andrea Belvedere | Flickr

James Salladin

James Salladin has served as rector of Emmanuel Anglican Church since the fall of 2016. Originally from California, he worked at St. John’s Vancouver Anglican Church and St James Muswell Hill in London. Jim completed his PhD through the University of St. Andrews with the focus of his research on grace and divine participation in Jonathan Edwards’s thought. He and his wife Amber have two sons, Caleb and Peter.

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