Laws of Logic

Note: Last Updated 7/29/2024.

Frank Turek:

     It sounded like he was saying that the laws of logic are just a human convention; that we human beings simply invent these laws in our minds but they don’t really exist outside of our minds. Several atheists have held this position, including Dr. Stein.

     When I asked Michael if that was his position, he said “yes.” So I then asked him, “Before there were any humans on the earth, was the statement, ‘There are no human beings on the earth,’ true?”

     Following a long pause, Michael gave a meandering response. After some prompting, he reluctantly admitted that the statement “likely” would be true (yet he continued to cling to the idea that the laws of logic were mere human conventions).

     Well, of course the statement would be true. And since there were no human minds to conceptualize it, the laws of logic can’t be a mere human convention. In addition, there are several other reasons to believe that the laws of logic are not human conventions—that they exist independently of human minds.

     First, human beings change, but logic doesn’t change. The laws of logic provide an unchanging independent measuring stick of truth across changing time, culture, and human belief. They are true everywhere, at every time, and for everyone. In fact, that’s why we call them laws—the laws of logic apply equally to all of us as do the laws of physics and math.

     Second, if we each had nothing more than our own private conceptions of the laws of logic, how could communication be possible? In order for Michael to understand me and for me to understand Michael, we each must be accessing something unchanging that transcends us yet is common to us. Those are the unchanging, immaterial laws of logic. Those laws provide the bridge between minds. They also provide a bridge to the outside world. Without that bridge, we’d be locked inside our own skulls unable to access or make sense of the external world. We use that bridge, but we didn’t invent it.

     Third, all debates presuppose that an objective truth exists outside the mind of each debater. Each debater is trying to show that his claims are closer to that objective truth than his opponent. Every truth claim—whether it’s “God exists” or “God doesn’t exist”—requires unchangeable laws of logic. If the laws of logic were changeable human conventions, then any thought anyone conceived would be “true,” even contradictory thoughts. So “God exists” and “God does not exist” would both be “true” at the same time and in the same sense. How absurd.

     Put another way, if the laws of logic were just inventions of the human mind, then every thought would have to be regarded as just an invention of the human mind. With no fixed laws by which we could reliably ground our thoughts, we couldn’t know anything confidently. That would include anything atheists or anyone else said.

     Finally, it’s self-defeating for Michael to assert that the laws of logic are a human convention. Notice that Michael thinks his claim is true regardless of how human minds conceptualize it. In other words, his very claim relies on the laws not being human conventions—it relies on them being fixed laws independent of human minds. In fact, all truth claims rely on that.

     Michael’s claim is self-defeating, which means for his claim to be true, it would have to be false.

(Frank Turek, Stealing from God: Why Atheists Need God to Make Their Case, [Colorado Springs: NavPress, 2015], pp. 32-33.)

Frank Turek:

     If the laws of logic are not mere conceptions of the human mind, then where do they come from? Most atheists avoid even asking that question. It’s like asking about the origin of the laws of nature. As Paul Davies found out (see chapter 1), asking such questions will get you plenty of support from atheist academics who will defend your right to shut up!

     They don’t want to talk about it because it’s an impossible question to answer from an atheistic perspective. That’s because the laws of logic are certainly not material. You’re not going to find the law of noncontradiction made of wood in your workshop somewhere. The laws of logic are immaterial realities that don’t change. All physical things change, but the laws of logic do not. They are fixed, immaterial, eternal laws that would not exist if the purely material world of atheism were correct. While atheists use them, they cannot explain them.

(Frank Turek, Stealing from God: Why Atheists Need God to Make Their Case, [Colorado Springs: NavPress, 2015], p. 35.)

Frank Turek:

     No. Any defense of reason by reason would be circular. Reason is a starting point. The question is, what grounds that starting point? Why do the laws of logic exist?

     I think Michael actually was on to something. He was correct to surmise that the laws of logic are grounded in a mind, but just not the temporal, changeable human mind he was advocating. Since the laws of logic are timeless, spaceless, immaterial, and unchangeable, they seem to be grounded in a timeless, spaceless, immaterial, and unchangeable Mind.

     Laws only come from lawgivers. That’s what all experience shows us. Why think the laws of nature and the laws of logic are exceptions? If we follow the evidence where it leads, it takes us right back to the same eternal Mind that created the universe.

     The same is true about the reliability of our minds and our ability to discover truth. If this universe is the result of a cosmic accident as atheists assert, then why isn’t everything chaotic? Why is reason so orderly? Why can we think, do science and mathematics, and arrive at true conclusions about the orderly external world?

     Men of genius who were not theists have pondered those questions. Einstein said, “The most incomprehensible thing about the universe is that it is comprehensible.” Physicist and mathematician Eugene Wigner wrote a famous article in 1960 called, “The Unreasonable Effectiveness of Mathematics in the Natural Sciences.” He was asking the question, “Why can the physical world be described so well mathematically?” He offered no firm answer. Einstein and Wigner were pondering those questions because they are foundational to math and science, which cannot be done without an orderly world and orderly minds.

     So why can we use our minds, logic, and mathematics to understand truths about the world? And what best explains the intersection between our minds and the orderly external reality?

     I think the best explanation begins with the philosophical theory called realism. Realism is the commonsense belief that there is a reality external to our minds that includes material and immaterial things. We can learn about that external, objective reality by starting with the self-evident laws of logic and then applying those laws to the data we get from our senses.

     How could mere molecules in motion explain our ability to do that? They can’t. So what is the ultimate explanation?

     If we are open-minded enough—meaning we haven’t ruled God out in advance by blindly putting our faith in the ideology of materialism—then we can see that our minds work because they are made in the image of the Great Mind. That is, our minds can apprehend truth and can reason about reality because they were built by the source of truth, reason, and reality. Our minds were designed by God to know God and His creation.

     …Let me also point out that this is not some kind of “God of the gaps” argument—since we can’t explain it by natural law, God must have done it. This is a positive case for God. In other words, it’s not just that atheism can’t explain the existence of the laws of logic and our ability to reason; it’s that those truths are positive evidence for a timeless, unchanging, intelligent Being that we call God.

(Frank Turek, Stealing from God: Why Atheists Need God to Make Their Case, [Colorado Springs: NavPress, 2015], pp. 35-37, 37.)

Jason Lyle:

     Rational reasoning involves using the laws of logic. Therefore, a rational worldview must be able to account for the existence of such laws. As an example, let’s just consider one of the laws of logic: the law of non-contradiction. This law states that any contradiction is false: you can’t have A and not-A at the same time and in the same relationship (where the letter A represents any claim). For example, the statement “My car is in the garage and it is not the case that my car is in the garage” is necessarily false by the law of non-contradiction. Any rational person would accept this law. But few people stop to ask, “Why is this law true? Why should there be a law of non-contradiction, or for that matter, any laws of reasoning?”

     The Christian can answer these questions. For the Christian there is an absolute standard for reasoning… 

(Jason Lyle, The Ultimate Proof of Creation, [Green Forest: Master Books, 2011], pp. 51-52.)

καὶ αὐτός ἐστιν πρὸ πάντων καὶ τὰ πάντα ἐν αὐτῷ συνέστηκεν ~ Soli Deo Gloria