In Defense of Logic

I received some surprising feedback lately from a fellow Christian pushing back against my emphasis on logic. The charge was even made that I “idolized” logic. Surprising (and saddening) as this is, I suppose it is worthwhile to review the role of logic in our lives. Now, I would never want to put anything, even logic, before God, but the simple fact of the matter is that we really can’t know God without logic. Don’t believe me? Let’s dig into that today by looking at 3 questions: What is logic? Is it necessary? And how does it apply to our understanding of God?

  1. First, what is logic? Is it some mysterious type of thought used by Vulcans, Mentats, and computers that is antithetical to Christianity?  Hardly. Logic is to thought as grammar is to language; it is the structure of thought. Logic is simply the organization of our thoughts into coherent structures that can have discernible meaning.  Without any further clarification, the statement “I am 5 feet tall and 6 feet tall”, would be nonsense to you. You might ask if I meant that my height was between those 2 numbers, or if I was talking about at different times of my life, or you might ask what the punchline was. Why would you not just accept that I existed in the form of 2 different body heights at the same time? Because it’s not possible. And we have a law in logic that puts that common sense notion into words. The law of non-contradiction states (in Aristotle’s formulation), that “the same property cannot both belong and not belong to the same subject at the same time in the same respect.” To have a body height of 5′ and 6′ at the same time, measured the same way, would necessarily be a contradiction and would be physically impossible. Because we cannot conceive any way something physical could be 2 different lengths at the same time in the same way, contradictions like that are truly nonsense. Now, it’s not like Aristotle (or anyone else) invented the laws of logic, anymore than Newton or Einstein invented gravity; these laws simply describe relationships that already exist. Logic is not a human invention, just a human discovery.
  2. Is logic really necessary? As Peter Kreeft points out in the preface to his logic textbook, “We all have used logic already, unconsciously, many times every day.” [1] He goes on to say, “One of the best remedies for bad reading and writing is good logic.” [2] Another professor laments that “logic is the very backbone of a true education, and yet it is seldom taught as such in American schools.”[3] While philosophy professors may bemoan the lack of logic instruction outside of their classrooms, that alone doesn’t make it actually necessary. In fact, you can certainly think without knowing logic, but only in the same way you can speak and write without knowing grammar – in both cases, the results will not be as coherent. Of course, the basics of logic, like the rather obvious law of non-contradiction,  are what we tend to call “common sense”, so even without knowing logic, it’s hard to not use it, even if used poorly at times. In fact, one typically has to resort to logic in any attempt to argue against it.
  3. So how does logic fit in with knowing God?  Classical logic systematizes our thoughts into three acts of the mind: understanding, judgement, and reasoning.
    • Understanding (or simple apprehension) is where we define our terms, where we understand what it is we are thinking about.  When we say that “God is good,” what do we mean by the terms “God” and “good”?  Many an unnecessary argument rages on because two opponents use the same terms but mean different things.
    • Judgement is that act of the mind where we make truth claims that must be accepted or rejected.Once we have our terms defined, judgement is what we say about those terms, those objects of our thoughts. We think about God, and judge that He is good. Our judgements are statements that are either true or false. There is no middle state between true and false, existence and non-existence, or any other condition and its negation (this is called the law of the excluded middle). If there is a middle option, then we have not been sufficiently specific in our initial statement.
    • Reasoning is where we establish why our judgements are true. This is the justification, warrant, or basis, for our statements or beliefs. Why do we think God is good? Think of valid reasoning as the foundation stones that support the structure made from true judgement of clear terms. Without valid reasoning, you can be accidentally correct about something, but your belief is just a house of cards waiting to be knocked over. Too many people rightly believe various truths about God, but for reasons like how it makes them feel, or that their parents told them these things. If they never dig any deeper to the real foundational reasons, then they are easy prey for the first skeptic that comes along and knocks these false supports out from under them.

Logic clarifies what is believed, deduces the necessary consequences of the belief, and applies it to difficult situations. [4]Let’s look at a prime example: the Trinity. This is core Christian doctrine. Indeed, it’s been said, “In the confession of the Trinity throbs the heart of the Christian religion: every error results from, or upon deeper reflection may be traced to, a wrong view of this doctrine.” [5] So why do we believe that God is triune? Because the church fathers had to wrestle with the tension between the clear teaching in the Bible regarding three divine Persons, and the equally clear teaching that the Lord our God is one God. But they very laboriously worked through precisely defining terms, judging what were true statements about those terms, reasoning through the serious implications of what they knew to be true, and applying that logic to discover this truth about the nature of God that we call the Trinity. The Trinitarian formulation is the result of resolving a paradox through logical reasoning.

As Professor Kreeft points out, the simplest and most important reason for studying logic is that “logic helps us to find truth”. [6] Jesus tells us in John 14:6 that He is “the Way, the Truth, and the Life.” Any tool that draws us closer to truth can draw us closer to Him. And that’s worth defending.


[1] Peter Kreeft, Socratic Logic (South Bend: St. Augustine’s Press, 2010), p. 12.
[2] ibid. p140.
[3] D.Q. McInerny, Being Logical: A Guide to Good Thinking, (New York: Random House, 2005), p. ix.
[4] Kreeft, p. 4.
[5] Herman Bavink, The Doctrine of God, p.285, as quoted in Wayne Grudem, Systematic Theology (Grand Rapids: Zondervan, 2000), p. 247.
[6] Kreeft, p.7.

An Uncomfortable God

“Christ with Thorns”, by Carl Heinrich Bloch, 1865-1879.

I was listening to an old teaching series by R.C. Sproul on “The Psychology of Atheism“, where he mentioned briefly that the God of Christianity was not a “comfortable god”, and I thought that insight worth pointing out here. Skeptics may like to believe that the Christian’s God is simply make-believe like the gods of ancient Greece or Rome, or the animistic gods of primitive cultures, but there’s a problem. God isn’t like any of the gods of every other religion. Look at any of those “gods” and you find very flawed, finite, humanesque creatures – “supermen” and “superwomen”, perhaps, but still no better than the humans they ruled over. One glaring example is that they could be bribed, but not so with God. While we might very much want justice against those who have harmed us, we tend to like a god that we can convince to “let us slide” when we are the guilty party. But the Bible is clear that there is no partiality with God [Deut 10:17, Rom 2:11, Eph 6:9], as much as we might prefer it at times.  Indeed, God will hold us accountable for every word and thought [Matt 12:36-37, Rom 14:12], even if we go through all the motions of fulfilling our obligations to Him [1Sam 15:22]. That’s a sobering thought for anyone. There’s no faking it with God, for He sees through our masks to the real us, the part of us we dare not reveal to our closest friend. That perfect, penetrating vision of us is what made philosopher Jean-Paul Sartre shudder, but that makes for an uncomfortably odd creation of our imagination if that’s all God is. But it gets stranger. Christianity alone teaches this concept of grace, that it is “by grace you have been saved,” that it is not because of anything we could do that we might be able to brag about [Eph 2:8-9]. As if God seeing through our facades and judging the ulterior motives of even our “good deeds” with perfect justice wasn’t frightening enough, there is no possibility of bribery or earning favor with God: it’s all on His discretion. Salvation is His free gift. Why make up a deity that puts us in the awkward position of being helpless to save ourselves, puts our best efforts to “be good” to shame, and holds us to a standard we could never meet? What would we gain from inventing a god like that?

On the other hand, what if the very existence of a physical universe required a first cause that existed outside of space and time in order for the effect of the universe to occur? This is simply applying the law of causality – that every effect requires an antecedent cause beyond itself. But if time and space had a beginning and are an effect, then their cause must exist beyond those dimensions. And that cause must be eternally self-existent. So then this cause would be eternal and ontologically necessary. But in that case, if there is ever to be a change in conditions, that first cause can’t be simply a physical force like gravity (note that there wouldn’t have been anything for a force to act on prior to anything existing…); rather, it has to be an agent that can choose to act, to create a beginning.  What if the design of our universe required an intelligent agent of power, genius, and foresight to the Nth degree? Would it not be appropriate to call that agent omnipotent and omniscient? What if that agent that brings everything into existence therefore has the rightful claim of ownership of everything He made? Would we not say He was “sovereign”? But then, what if this Supreme Being wasn’t simply some powerful universal tyrant, but was loving, the very source of love, in fact [1Jn 4:8,10,19, Rom 5:8]? And what if, in creating creatures “in His own image” who chose to rebel against Him and make a mess out of things, He still loved us? Could He not reach out to us, and communicate to us, and work to redeem us from our brokenness, and reconcile us to Him [2Cor 5:19-21]? But if He were perfectly just, as well, the crimes of mankind must still be paid for, no matter how much He loved us. We can easily see that granting a serial killer a pardon would be a great offense to the families of his victims desiring justice. But under God’s perfect standard, we are all guilty [Rom 3:10,23, 6:23]. How would He demonstrate perfect love and perfect justice without compromising either? What if He, out of His unfathomable love, paid the penalty for our transgressions, and offered us the reward: new life for the death row inmate!? [Rom 5:6,8-10]

I know that’s a lot of “what ifs” there, and covers a whole lot of ground in one paragraph, but if those are actually the way things are, then Christianity has unparalleled explanatory power for what we find when we try to investigate where we came from, where we’re going, and everything in between. And when we do start doing the serious digging, we do find those to be the case. We see philosophically the need for an uncaused first cause and that it has to be independent of the time-space framework. And so far as cosmologists have been able to verify with scientific observation, space and time really do appear to have a definite beginning, confirming what we deduce through philosophy. The more we learn of the workings of our universe, the more mind-bogglingly complex designs we discover – ones that put anything humans have ever invented to shame. And we see this from the macroscopic systems of our universe to the microscopic systems of our cells and every level in between. We have an innate sense that things are broken in our world; it seems like we were meant for more, but things have been twisted and corrupted, and that things are not as they should be. We feel a tension between humanity’s call to greatness on the one hand, and our abysmal wretchedness and inability to fulfill that purpose on our own on the other hand.

The Christian God would not be a very comfortable, soothing figment of our imagination if that’s all He were. Not only does He tower over us, but He also stoops to pick us up, yet not of any merit of ours, but only out of His own love, and mercy, and grace. He destroys all our pretensions, turns our world upside-down, and actually changes us from the inside out. And that’s the uncomfortable truth that we could never invent.

The Unwanted Cure

“Family Doctor”, by Grant Wood, 1940.

What would you do if you found out you had cancer? You’d probably be in shock first, but as that initial shock wore off, what would be your plan? Would you aggressively fight for your life? Would you follow your doctor’s advice like you never have before? Would you sell all you had to finance treatment? Would you consider experimental medical procedures  if more typical medical solutions didn’t work? Or would you just carry on with life as it was before you got the diagnosis? Would pursuing the cure be too much work to bother with?

We all have a disease – a terminal disease called sin [Rom 6:23].  This disease has a cure, though. That cure is called the Gospel. Gospel literally means “good news”. If you had an advanced stage of cancer, and certain death was fast approaching, and someone told you that there was a treatment regimen that would cure you of the cancer, saying that was “good news” would be an understatement! But getting the benefits of that cure requires something so basic, you might not think about it: it requires admitting that you have cancer. You obviously wouldn’t need a cancer cure if you didn’t have cancer.

But the Gospel is a cure for a problem we don’t want to admit we have. Like an alcoholic or drug addict, admitting we have a problem is the first step. People can see God’s grace as offensive because they don’t think they need it. I’m afraid one reason people in our generation think they don’t need it is because all they’ve heard from Christians is “God loves you.” And while that’s true, they hear that over and over again and think, “Why wouldn’t He? I’m a pretty good person.” I’ve had several friends and family members now that have battled cancer, undergoing surgeries, chemo, radiation, or some combination. Some won that fight, others lost. But chemo and radiation and surgeries are only ever good news when you understand that your sickness is going to kill you. Almost every book in the New Testament warns us that if we choose to follow Christ, we will suffer trials, hardships, mockings, torture, imprisonment, and death. Is that being overly dramatic? Ask the Christians being beheaded in the Middle East, or the Christians imprisoned in North Korea and Iran. Read Foxe’s Book of Martyrs. Read Paul’s account of his own sufferings. Why go through that? All of those people understood what God saved them from, and just how good the Good News really was. As Peter said when Jesus asked if the 12 disciples would abandon Him like the fickle crowds had, “Lord, to whom would we go? You have the words of eternal life.” [Jn 6:68 NET]

So is there anything that confirms the diagnosis? The Law of God is the test that reveals the need for the cure of the gospel of grace. His Law reveals our inability to keep His perfect standard. It shows us that being “pretty good” doesn’t help. We can win the Nobel Peace Prize, and every humanitarian award there is, and still find ourselves failing to meet God’s perfect standard just like Hitler and all the worst examples of humanity. Talk about a blow to one’s pride! The best we could ever hope to do isn’t enough. That’s the bad news; that’s the cancer diagnosis. We’re going to die without intervention. But it gets worse. We’re going to die as rebels and traitors before a perfectly just God. And He wouldn’t be just if He didn’t punish lawbreakers.  What are we to do? What can we do? Nothing, really. You might wonder, “Are we just ‘dead men walking’ then? Pretty much. “That’s kind of depressing, isn’t it?” Yep….

Thankfully, that’s not the end of the story. Where we are powerless to stop this disease, God provides a cure, as only He can. And notice the design of His cure: both powerful to save, and available to save. God’s salvation is not limited only to the rich who can afford it, or the genius who can comprehend it, or those of some supposedly superior race who deserve it, or of a particular societal class entitled to it, or to those born into the right family to inherit it, or those who have lived long enough and worked hard enough to earn the cure, or to those who showed the most potential. Those are all ways us humans might try to determine who qualifies for something so precious, if we were in charge. Rather, God sent Jesus, his only Son, to live the perfect life we never could, to fulfill the Law in every detail, and to be the only sacrifice that could satisfy what justice demanded. God’s gracious gift of salvation is open to the Wall Street banker and the Main Street beggar, the quantum physicist and the ignorant child, people of all races, the upper crust and poorest of the poor and all the middle class in between, the zealot that has sought after God since he was in a crib and the militant atheist on his deathbed, the sons and daughters of privilege to the loneliest orphan, the child prodigy to the unknown pariah. Maybe you’ve heard Romans 3:23, that “all have sinned and fall short of the glory of God…”, and felt the condemnation there. That’s good, actually, but only as a start! The truth hurts, but nothing like the consequences of ignoring it. Now keep reading to the end of that sentence in verse 24: “… being justified as a gift by His grace through the redemption which is in Christ Jesus.” [Rom 3:23-24] We’ve all sinned, but see the unsurpassable love of God!  – that we may be justified before Him simply by trusting in the redeeming work of Jesus. Have you acknowledged the sickness of your sin? Have you laid aside your pride and trusted Jesus alone to cleanse you of the gangrene of your soul? Or will you choose to turn down the free cure?


For further reading, Alexander Maclaren does a beautiful job, far better than I ever could, of explaining the passage from Romans referenced above.
Alexander MacLaren, Expositions of Holy Scriptures: Romans & Corinthians, Romans3:19-26. http://www.ccel.org/ccel/maclaren/rom_cor.ii.vii.html

 

A Two-Pronged Attack

Infantry land on Utah Beach on the east side of Cotentin Peninsula, while Airborne parachuted in from the west. US Army Brochure.

73 years ago, on June 6, 1944, the largest amphibious assault in history hit the beaches of Normandy, France, to begin a slow marathon to Berlin, the seat of Nazi power. To facilitate gaining a foothold on the Nazi-controlled continent, the landings at 5 separate beaches along a 50-mile stretch of the Normandy coast were also coordinated with airborne infantry dropping behind enemy lines to clear the way inland for the (hopefully) successful beach landings. The foothold was costly and took time, but it eventually led to Allied victory over Hitler. But what I want to discus today is a different kind of attack: one on a grander scale even than D-Day; an attack with bigger objectives than the liberation of Europe from Nazi occupation; an attack formulated by a greater Supreme Commander than General Eisenhower.

What I’m writing of is God’s assault that He launches against the walled fortress of each human heart. You see, we are rebels every one, fit only for court-martial and subsequent execution by a perfectly just Ruler over all.  When the standard is perfection, there are no “little sins”, no peccadilloes, no “white lies”, no minor indiscretions. Not acing that test is the same as failing, and since none of us are perfect, we all fail. But God, in His sovereignty and amazing love and grace, doesn’t leverage His omnipotent power against us, obliterating us like so many flies in a nuclear blast.  Instead, His purpose was not to destroy us rebels, but to redeem us, to transform “children of wrath” [Eph 2:3] into “adopted children of God” [Eph 1:5].  How does He do that? There are many ways to analyze His strategy, but I see a two-pronged attack of reason and love at work.

We find justification for believing in God’s existence and in the truth of what the Bible records about Him through science and philosophy, or our observations of the world around us and our critical thinking. We can apply logic to the question of God’s existence in the form of arguments such as the Cosmological, Teleological, Axiological, and Ontological arguments, among others, and rationally deduce that God exists. With the Cosmological and Teleological arguments in particular, we can support those premises with our scientific observations of the universe around us. Indeed, the apostle Paul tells us that God’s eternal power and divine nature can be clearly seen from what is created, so that men are without excuse [Rom 1:20]. We can examine the historicity of the biblical manuscripts, their supreme coherence, both internally and with the external world,  and their explanatory power in comparison to other religions and ideologies, and see that Christianity provides the  most reasonable explanation of human history, of our paradoxical greatness and wretchedness, as Pascal would say.

Not everyone would surrender based on evidence and reasoning, though. Some might shy away from those avenues to God, thinking they were too complicated to bother with, or beyond their abilities. Some on the other end of the spectrum would dig in their  heels all the more in response to reasons contrary to their views. They would feel the directness of cold, hard logic, and batten the doors of their fortress all the more. Childishly, we can resent being told anything contrary to our desire for personal autonomy, even when it’s for our own good. But defenses strengthened against one attack may yield to another. And God has a flank attack:  He loves us. Not with some momentary warm fuzzy kind of so-called love that soon passes, but with a sacrificial love for those who hated Him. For, “while we were yet sinners, Christ died for us” [Rom 5:8, I Jn 4:10,19], “the just for the unjust” [1 Pet 3:18]. Because He created us in His image [Gen 1:27], we have intrinsic value, even if the rest of the world tells us we aren’t smart enough, attractive enough, cool enough, or any other comparison they can find to feel better at our expense.  And when people look at our past mistakes and ask, “Who could ever love someone like that?”, the answer is, God. He did, He does, and He will. Love is a powerful craving in all of us, and we seek it in all the worst places sometimes. And those pursuits don’t satisfy, so we keep running to the next big thing that we think will be the end of our search. All the while, our loving Creator awaits, extending an invitation to each of us, not desiring that any should perish {Ezek 33:11], but still obligated by His perfectly just nature to punish all who reject his loving offer of salvation [Rom 2:4-6].

Some yield to God’s logic and others to His love,  but they are just two sides of the same divine battle plan to redeem a chosen people. For me, 25 years ago, my sinfulness, God’s perfection, and my need to come to Him on His terms rather than mine were as obvious and rational to me as 2+2 equaling 4. There was simply no justifiable reason to reject God’s gift. And the deeper I have dug, and the more I have researched other worldviews and religions, the more I “know whom I have believed and I am convinced that He is able to guard what I have entrusted to Him until that day” [2 Tim 1:12]. Whatever way God uses to reach you, don’t reject His offer. It does require unconditional surrender on our part – something our prideful hearts bristle at – but like the Nazis in WWII, we’re actually on the wrong side, and the best thing we can do is surrender to our just, but loving, Lord.