Why Teach the Five Ways?

I teach apologetics, and I recently wrapped up teaching a unit to my students on the five proofs for the existence of God. In apologetics, the first thing everyone tends to think of is arguments for the existence of God. But in a day and age suspicious toward metaphysics and recourse to a seemingly infinite number of more compelling arguments for the existence of God, why did I insist my students learn these classical proofs? Afterall, students are not likely to come upon anyone who denies the existence of God because of their views on motion or change (Aquinas’ 1st and 2nd Ways), and the odds of someone challenging the existence of God due to the nature of possible beings or the perfection of being is probably close to zero (Aquinas’ 3rd Way and 4th Ways). If I were to guess, the most likely line of argumentation might be on the idea of governance (Aquinas’ 5th way). Even so, it will probably take the shape of something akin to Intelligent Design and not the proof from governance specifically. However, I would like to challenge that assumption. The Five Ways are not mere relics of the past, useful in an age where metaphysics ruled until physics could take its place. There is still a vital need for the classical proofs, and in this short column, I would like to provide our readers with three reasons for this. 

Let’s Slow Down

A common objection to teaching the five ways is that there are simply more compelling arguments. We live with a profound depth of knowledge about the natural world that the older generations could scarcely imagine. Arguments from intelligent design or the fine-tuning argument would seem to offer a more compelling answer to the questions our secular culture asks today. After all, the sheer amount of information contained in DNA or the necessity of the gravitational constant for the flourishing of life speak more directly to the kinds of things our science-driven culture values. We can take a real photo of a black hole 55 million light-years away, and physicists can now split atoms, the most fundamental building blocks of our universe. In fact, it is this increase in scientific knowledge that is used to reject God’s existence in the first place. Would not our time be better served making appeals through these amazing natural phenomena that cry out for an explanation beyond themselves?  

Yet it is here I would encourage any intrepid apologist to slow down and ask why such appeals are compelling in the first place. What is it about the being of such phenomena that demands a Creator to fully explain them? Further, what must be true about the nature of this Creator, given what we are appealing to? These questions demand an answer, and their answers serve as a foundation from which all other arguments are built. Most of the time, these answers go unspoken and serve as presuppositions that are not worth the time explaining or defending. I disagree with that approach.

Much like the conservation of energy, metaphysics cannot be created or destroyed by an increase in scientific knowledge. Share on X

The answers to these questions lie at the heart of these classical proofs for the existence of God. Such questions are metaphysical questions that, though ignored by many today, have not disappeared. Much like the conservation of energy, metaphysics cannot be created or destroyed by an increase in scientific knowledge. In any argument for the existence of God, appeals to natural phenomena use evidence that is not self-explanatory. If one wants to get the skeptic to appreciate the full weight of Intelligent Design arguments, one must eventually come to understand that the law of causality demands that change and efficient causes cannot go back to infinity. So, if the skeptic wants to posit an infinite series of universes that create one another, he needs to know that this is an objection that Aquinas answered almost a 800 years ago: “But if in efficient causes it is possible to go on to infinity, there will be no first efficient cause, neither will there be an ultimate effect, nor any intermediate efficient causes; all of which is plainly false” (ST 1.2.3). Reason, not simply faith, demands that when we observe causation, any causation, in the universe, we are compelled to posit the existence of a being who is un-caused, yet is the source of all cause. Or, we can ask our skeptic if anything we observe in this universe must exist. If not, then reason demands that there must be some being whose existence is not only possible but necessary, existing of itself and depending on nothing else for its existence. Without this necessary being, not even our apologist would have sufficient metaphysical grounds to explain all that we observe in this wondrous universe of ours.

Without a necessary being, not even our apologist would have sufficient metaphysical grounds to explain all that we observe in this wondrous universe of ours. Share on X

If we allow ourselves to slow down and force both ourselves and our students to wrestle with the nature of being as such, they all will be leaps and bounds further along than even the most ardent critic of our holy faith.   

All Are Without Excuse

Yet, how can these five proofs be useful to a Christian in an apologetic setting? After all, none of them prove in and of themselves that the Christian God exists. This is a fair point. It is true that the Five Ways are not sufficient, but that does not mean they are useless. One thing I tried to demonstrate to my students is that these arguments, because they can be understood through reason, and because they all start with observations in nature, leave all men without excuse before God. 

That might sound like a bold claim, but I am following the logic of Paul in Romans 1:19-20. God’s eternal power and divine nature have been clearly perceived in the things that have been made. In other words, the nature of God, which is proved in the Five Ways, is part of what is clearly perceived in the created universe. Because every human being has a rational soul, they can observe the universe and come to the rationally necessary conclusion of an un-moved Mover, an un-caused Cause, a necessary Being, a perfect source of all Being, and the source of all ends. Put simply, God’s existence is plain to all because God has shown it to them. The Five Ways spell out what the unbeliever should know and recognize about the existence of God simply by being human.

Without First Principles, What’s the Point?

Lastly, I want to make a practical appeal. We must ask ourselves what the point of all this arguing is if we are not solid on first principles. Why teach our students or our church members so many arguments for the existence of God if their understanding of the nature of reality remains rudimentary at best or fundamentally wrong at worst? Being is as objective as truth; in fact, truth depends on being(see the 4th Way). When we are defending the existence of God, we are defending not just that he exists, but the nature of his existence, and by proxy, the nature of all that exists. For too long, we have let the metaphysics of being take a back seat in our apologetics. We are simply trying to out-argue our opponents without addressing the reality underneath all of our evidence. We teach our students tactics as weapons, instead of appealing to the nature of reality itself. This is a short-term strategy.

Being is as objective as truth; in fact, truth depends on being. Share on X

If we want our students and our churches to be able to defend the faith once for all delivered to the saints, they must understand the world in which that faith is lived out and the One from whom all other beings receive their being. They must know and defend the first principles of reality, which are nowhere more concisely articulated than in the Five Ways of St. Thomas Aquinas.

photo credit: public domain