Studying Logic

How do you go about studying the topic of logic? Let’s plunge into the Deeper Waters and find out.

I’ve been discussing lately with some fellow Christians the study of logic. We’ve often discussed the main ways that people study logic, such as reading the books on logic and listening to great teachers on logic. This is essential to the study and you should do this, but at the same time, I want to point out some fun ways you can put into practice what you are studying.

One place to go to is advertising. Someone is selling you a product. Why should you buy it? What claims do they make? Do they really convince you that this is a worthwhile exchange for your money, or do they do something else, say have a bikini wearing model advertise a burger for you? (And let’s face it, we all know that model never ever eats anything like that.)

Sometimes, businesses are less forward than that and try to sneak in an attitude. When we lived in Tennessee, a local bank would have commercials with a touching country setting emphasizing the goodness of home. Nothing was said about the bank itself, but the feeling you got thinking about the homey atmosphere was meant to carry over to the bank. Car insurance companies have been doing this as well using humor. How many of us laugh at the “Jake from State Farm” commercials or the GEICO commercials about cats, mothers, and the band Europe? You know what? They work, because we talk about these commercials, but many times you don’t really wind up knowing much about the product.

I have also been a stickler for pointing out to my wife Allie what it means when someone is referred to as a liar. Because someone gets a claim wrong does not mean that they are a liar. If that is so, every student who gets a false answer on a math test is a liar. A liar is someone who knows the truth about what they are saying and says the opposite fully intending what they say to be believed as the truth. We have to be clear because someone could say the exact opposite in sarcasm not intending to be believed at all. This kind of thing happens often in politics. It’s too easy to say someone is a liar for providing information that is false. Maybe they are, but it takes more than false information to show that someone is lying.

Speaking of politics, let’s look at the presidential debates we have going on now. This is a great place to go to to study logic because you can look at a question a candidate is asked and then look at the answer and ask “Did they really answer the question?” You can also ask how they did that with a question or challenge they receive from an opponent.

By the way, when you do this, it’s important to try to be as impartial as you can. Let’s say you’re a Ted Cruz supporter in the Republican primary. You might be looking to see what Donald Trump says that is an example of bad logic or an answer that does not follow or dodges the question. That’s fine. Do the same for Cruz also. If you’re a Trump supporter, you will do the opposite. You should also be willing to admit when your opponent does answer the question satisfactorily. You can debate how good the answer is how effective a strategy would be, but does he answer the question?

Humor is also a good place to go to. Comedians don’t try to be logicians, but they do try to point out the humor in our thinking. If you like puns, puns rely on ambiguity largely. That’s what makes them so funny. Much of our humor relies on taking people literally. My wife and I were just seeing someone and getting set to make another appointment and they said we can make it for whenever we want. I replied midnight would work just fine for us. Of course, that wouldn’t work for them, but that was the humor of it. On The Big Bang Theory, Sheldon Cooper regularly does this sort of thing.

Finally, if you’re doing this from an apologetics perspective, consider watching to and listening to debates. One of my favorite programs for debates is Unbelievable? with Justin Brierley. Try to be impartial. Ask and see what side really makes the better case. I have heard debates where I had to say the non-Christian made a better case and some where sadly, the Christian case was just embarrassing in its defense. It does not mean that I think the non-Christian was right, but it does mean that I think they did a better job presenting their case. One mistake it’s easy to make is to think that if an argument agrees with your conclusion, it must be a good one. Christians and atheists both sadly have a habit of going to Google, finding the first thing that they think agrees with them, and sharing it because they think it agrees with what they already believe and so it must be a good argument.

Studying logic in this can be fun and eye-opening and prepare you for a world where people are going to be consistently trying to snow you. Many will do this unintentionally. Some will do it intentionally. If you can learn to think through what people say better, you will be a step ahead of the game. Even if you don’t know a topic well, you can at least see how well conclusions follow.

In Christ,
Nick Peters

The Burden of Proof

Who has the burden of proof? Let’s plunge into the Deeper Waters and find out.

Recently I wrote a piece responding to Neil Carter and posted it on the blog of his that I was responding to. Carter responded by saying he stopped after I said that if you want to disprove Christianity, you have to disprove the resurrection. I was later told that I was someone who obviously did not understand what is meant by the term burden or proof.

Seeing as this is the kind of topic that comes up often, I figured I should write about it.

Too often in debates, one person assumes that the other side has the burden of proof. This also comes with claims like “Extraordinary claims require extraordinary evidence.” Unfortunately, a lot of internet skeptics I meet treat skepticism as if it is the default position and anyone else arguing otherwise has the burden to prove. It is said that the existence of God is an extraordinary claim, but why should this be so? Many theists would say that atheism is an extraordinary claim. Some would also say that macroevolution being true is an extraordinary claim. Hence the problem. This is entirely subjective.

Now when it comes to my response to Carter, my claim is that if you want to argue that Christianity is false, you have the burden to show that. Why is that the case? Because he was making the claim about an argument that was to show Christianity is false. It’s my contention that you could have an unexplained problem for Christianity, but that doesn’t disprove Christianity’s central claim.

Let’s use the problem of evil as an example. If there’s one question that can be hard to answer sometimes, it’s the problem of evil, especially when you get to the personal level. “Why did my son die in a car accident?” “Why did my loved one commit suicide?” “Why does God allow sex trafficking to go on?” Now note something interesting here. What the bringer of the objector must do in this case is not only say that these are hard questions and good questions, and they are, but that these are somehow a categorical disproof that God does not exist.

You could say this perhaps lowers in your eyes the probability that God exists, but to say that it is a disproof is something else altogether. Who has the burden to show that it is an absolute disproof? It is the person who is making the objection. Let’s suppose this person makes the objection as to why God allows XYZ to happen and the Christian just says “I don’t know.” Now sure, we could say the Christian should be more equipped perhaps, but we cannot say that the challenger has proven his point simply by raising the objection. Frankly, every worldview that anyone holds will have some unknown facets to it. If you have a worldview and you lack questions you just don’t know the answer to, you’re not taking your worldview seriously.

To be fair, let’s put the shoe on the other foot. Let’s suppose the Christian says “God raised Jesus from the dead.” The atheist responds “I don’t think so.” The Christian could say “Well unless you can tell me what really happened, then Christianity is true.” This is also not a good argument. It could be made about any position such as God revealed himself to Muhammad or Joseph Smith. The inability of the atheist to offer a good position does not mean the position of the Christian is true.

But let’s suppose that instead of just saying what was said above, the Christian makes a case using scholarly sources and then says “Therefore, Jesus was raised from the dead as this is the best explanation of the data.” The Christian has met his burden then. It does not mean everyone will find it convincing, but it means he has made his case. In this case, skepticism of the claim is not an argument. The skeptic cannot say “I am not persuaded, therefore your case is false.” If so, this would work for any position. “I am not persuaded by your case for evolution, therefore your case for it is false.”

Now let’s suppose a Christian and an atheist are debating the existence of God. The Christian makes his case and then the atheist shows that the argument has a logical fallacy in it and just does not work. Does this mean theism is false? No. Does this mean atheism is true? No. It means that the argument that was given is a poor reason. At best, we could end up with agnosticism. The only exception would be if there was no middle ground whatsoever. If it’s either A or non-A exclusively, then the disproof of one equals the proof of the other.

A simple rule to keep in mind then is that whoever makes a claim has the burden to back that claim. If you enter the debate and make any claim whatsoever, you have the burden to back that claim. If you are merely rebutting a claim, you have no burden to make your own case. In my above case that started this, I was under no obligation to make a full case for Christianity to show that an argument against it is false. I have frankly as a Christian said some arguments against atheism are bad arguments and should not be used. Rebutting a bad argument for Christianity does not mean that Christianity is false and atheism is true and rebutting a bad argument for atheism does not mean atheism is false and Christianity is true.

The avoiding of backing your own argument leads us too often to sit back and let the other person do all the work. If you are going to be a good debater, you have to hold your side up of the intellectual conversation. Unfortunately for many, that means you actually have to work and study and read books. That’s anathema to many people to be sure, but there are no easy wins in the world of serious debate. You must do your part.

In Christ,

Nick Peters

Don’t Be Confused By Truth

Hello everyone and welcome back to Deeper Waters where we are diving into the ocean of truth! First off, I ask your prayers for my grandmother. She’s not doing well. My wife and I will be away from Wednesday to Sunday night definitely for Thanksgiving, but if I’m seemingly absent earlier, you can know that the worst has happened.

We’ve been talking about becoming a thinking Christian and using logic to do such. Tonight, I’d like for you to keep an important principle in mind when evaluating a syllogism. Do not be confused by the truth. This sounds odd coming from an apologist, but when evaluating a syllogism, we are not evaluating right off if it is true or false. We are evaluating if it is valid or invalid.

Consider the following syllogism:

Lassie is a turtle.
All turtles have wings.
Lassie has wings.

There is no truth to this. Lassie is a dog and turtles do not have wings, but the syllogism itself is entirely valid. It has three terms. It follows the proper rules of distribution. A way to check is to replace terms with ones you know would be true without changing the form.

Lassie is a dog.
All dogs have four legs.
Lassie has four legs.

The form is exactly the same and that’s what we’re interested in is the form. All you want to know at this stage of thinking is if the form is valid or not. You don’t care if the conclusion is true. After all, there wouldn’t be much of a system if it was simply “Any argument is valid as long as the conclusion is true.”

For instance, as an apologist, I definitely defend the proposition that God exists. However, it does not mean that I am forced to defend every argument for God’s existence. It might be controversial, but I do not support the ontological argument. Now I definitely agree with Saint Anselm’s conclusion. That does not mean that I have to support an argument that I do not think works. If someone thinks it works, then they’re free to defend it. If you don’t think the five ways of Aquinas work, I disagree, but I won’t obligate you to defend them.

So what if the conclusion is one you don’t think is true? Then you can either examine the form or question one of the premises. There are no other choices. Of course, if Christianity is true, there is no logical argument that can be brought against it that truly succeeds. You can always find something questionable about one of the premises and that is exactly what you will need to do in order to be a good thinker.

This is the technique I use as well. When attacking an argument, I find it more important to look at the underlying presuppositions to the argument rather than the argument itself. In fact, that is where the argument is won, in the premises. When looking at the argument, do not be fooled by truth. Examine the argument as a whole.


Hello everyone and welcome back to Deeper Waters where we are diving into the ocean of truth! Tonight, we’re going to be continuing our look at becoming a thinking Christian. We started discussing logic some last night and tonight, I’d like to continue that by having us look at terminology.

Words. Words are wonderful things. It is amazing that they can convey information often so well. Those who doubt what I am saying are proving what I am saying as my words to you right now are conveying my thoughts. It could be that some of my thoughts are wrong, to which I’m sure some are, but I would hope that I am at least conveying what is wrong truthfully so it could be corrected if need be.

My wife is one who knows about my usage of words. I have a joy of taking words literally at times to laugh about them. For instance, if we’re going down the highway and I see a billboard that says something like “McDonald’s: Exit now!” I can just say “Well I guess if we want to go we have to drive right off of this bridge!”

In logic, your words are important also. All syllogisms only have three terms. Those are the minor, major, and middle. What’s important is that we be clear on what the terms mean. Terms also does not mean that they are one-word only. They can be, but they do not have to be. I could say “The lamp that is sitting to my right of me as I type on my computer” and have that be a term. “Everything in the kitchen except the kitchen sink” is a term.

Of course, there is a danger that a term could be identical in word and different in meaning. To illustrate this, a simple syllogism.

The edge of a river is a bank.
Banks contain money.
Therefore, the edge of a river contains money.

The premises to this are true. (Although granted that an agnostic friend of mine pointed out to me that the second premise can easily be questioned today) The AAA type proposition is usually valid entirely. However, the problem to this is that the term bank is ambiguous.

In the second premise, when we speak of a bank that contains money, we refer to a place of business that has the responsibility of holding money if need be for your safekeeping. (Again, I do realize that that is questionable today) In the first premise, we are speaking of the edge of a river.

The fallacy then is that while we’re using the same word, we refer to two different things. In essence, this becomes the four-term fallacy. This is also important in informal debate and one reason I try to make sure my opponent and I define our terms clearly. What do you mean by God? What do you mean by good? If you are using the same term and you have a different referent to that term, you’re going to be talking past each other.

God takes words seriously. Let’s make sure we do the same.


Hello everyone and welcome back to Deeper Waters where we are diving into the ocean of truth. We’ve been looking lately at what it means to become a thinking Christian and the next step to take is to learn something about thinking. That means logic. Logic doesn’t just mean right thinking. There are rules to thinking. There are a number of people who think that they are logical and they do not know the first thing about forming a syllogism.

Keep in mind this important truth. Logic is not a tool to discover truth per se. It is a tool to guide your thinking to see if something is true or false, but it itself cannot determine if something is true. It can determine if an argument is false if it is invalid, but that does not mean that the conclusion is false. I will demonstrate this with a few syllogism as I go along. Let’s start with the classic one.

All men are mortal.
Socrates is a man.
Socrates is mortal.

This is a valid syllogism and a true one. The important point with validity is that if a syllogism is valid in its form with true premises, then the conclusion MUST be true. The first sentence is called the major premise because it contains the major term, which will be the predicate in the conclusion. The second sentence is the minor premise as it contains the minor term, the subject of the conclusion. The term showing up in the premises but not the conclusion is the middle term.

Now let’s consider this syllogism.

All angels are rational.
Gabriel is rational.
Gabriel is an angel.

If you are a Christian, you could be quite tempted to immediately say that this syllogism is valid. We can agree with the conclusion, but the argument to get there doesn’t work. Want the proof? Take out Gabriel and put in your name and then tell me if you’re ontologically an angel. (I know some of you are really good people, and I don’t mean an angel in that way.) Gabriel could be the name of your next-door neighbor and while he is rational, he is not an angel.

The fallacy that has taken place is that of undistributed middle. A classic example of this was committed by a poster on Theologyweb with this syllogism. (To this day, he has not admitted it is invalid.)

All basketballs are round.
The Earth is round.
The Earth is a basketball.

The fallacy is called undistributed middle. In logic, there are four types of propositions.

A = All S is P.
E = No S is P.
I = Some S is P
O = Some S is not P.

A term is distributed if it refers to the entire class of which it speaks. In an A term, the subject is distributed. In an E term, the subject and predicate are distributed. In an I term, none of them are. In an O term, the predicate is. A rule is that the middle term MUST be distributed at least once.

Looking at the first syllogism, we find that rational is not distributed as rational is a predicate in both premises that are A premises. Therefore, the syllogism is invalid.

Note also that if you have a term distributed in the conclusion, it must be in the premises. Consider the following:

All snakes are reptiles.
No turtles are snakes.
No turtles are reptiles.

The problem is that reptiles is distributed in the conclusion, but it is not in the premise. Since this is the major term, it is the fallacy of illicit major. To do so with the minor term would be the fallacy of illicit minor.

This has been a brief look. We’ll discuss more tomorrow.

Logical Fallacies: Accident

Hello everyone and welcome back to Deeper Waters, where we are diving into the ocean of truth. I’m going to take another look at a logical fallacy tonight and it will be the fallacy of accident. No. It doesn’t mean just making a mistake in your reasoning, though you shouldn’t do that.

We all make generalizations at times. I’m not saying that’s wrong. I don’t really know much of a way that we can avoid it. The problem with the fallacy of accident is that it takes a general statement and treats it as if there could be no exceptions whatsoever to that statement.

A good example of this in biblical studies is the book of Proverbs. We all know of people who have said that the book of Proverbs says X, and they did X, but it did not happen. For instance, not everyone who does good has a long life. Proverbs however are not meant to be ironclad statements of reality that always follows. They are general principles that tend to lead to a desired result. Chances are, if you live life the way you ought to, you will live a longer life.

This is often the case with moral dilemmas. What do you do about the Nazis who come to your door and ask you if you have any Jews? Generally, we would agree that you should tell people the truth. However, this is a case where I would argue that the Nazis do not deserve the truth and it is justified to lie to them. You could lie to them while still believing in the ninth commandment since you realize a valid exception to the rules.

This is another one that skeptics also have a problem with, especially when it comes to miracles. We are told that the laws of nature have no exceptions whatsoever to them. If that is the case, then there can be no miracles. We’ve seen hundreds of cases after all where people die and they stay dead. Why should we believe that a miracle has taken place?

The Christian arguing for the resurrection however is not arguing against the principle that dead people come back to life by natural means. That would be pretty silly. They in fact agree with the principle. If they did not, it would not make a resurrection so incredible. It would be a case of “Well yeah. That guy came back from the dead. It happens every now and then. So what?” Death itself has to be a constant reality for the resurrection to be considered a miracle.

What the Christian is saying that all things being equal, dead people do stay dead, but in the case of Jesus, things are not equal. There is an outside agent interfering that brings about the resurrection. You don’t have to start with the outside agent, namely God. You can argue that Jesus was raised and then from that point determine that there must have been an outside agent and then establish the identity of said agent.

The one claiming there are no exceptions to dead people staying dead is making an a priori judgment. It could be the case that no miracles have occurred, but it is hardly fair to the evidence to assume this prior and then look back and when you see what could be an event that is miraculous, throw it out ad hoc.

Be wary of generalizations. They are not always absolute rules.

Logical Fallacies: Accent

Hello everyone and welcome back to Deeper Waters where we are diving into the ocean of truth! I’d like to start tonight a look at the topic of logic, and mainly of logical fallacies. These are fallacies that can often take place in debate. Normally, when we do debates, we don’t come out listing premises and conclusions, even if we have these in our minds. Thus, formal logic will be looked at later. For now, we’re going to look at some informal fallacies that anyone can catch.

A caveat needs to be made at the start. Because a fallacy is used, it doesn’t mean the conclusion reached is automatically wrong. It just means that there is not a good idea given to hold to that view. For instance, if I said “I believe in God because most of the world believes in God so it must be true”, that would be the ad populum fallacy. Now it could be the case, as it is, that God exists, but that is not a valid reason in itself. (I would accept it as evidence however though not an airtight conclusion) Consider also if someone said “I don’t believe in God because Hollywood Celebrity X doesn’t believe in God.” Now it could be, which it isn’t, that God doesn’t exist, but that is not a good reason for disbelieving in God’s existence. As Christians, we want not only good conclusions, but also reaching good conclusions by good means.

I plan to go through a list alphabetically of these fallacies. For all interested, if you have an IPhone or IPad, you can get an application called “Cheatsheet” for a relatively low price that contains each of these. The first one will be the fallacy of accent.

This one can be harder to detect in the online world unless someone uses something like bold, italics, or capital letters. In speeches however, it’s simple to detect. The fallacy takes place when one word or phrase is given an accent as if to highlight what is meant and even go against what was meant.

Suppose you were being interviewed in a man-on-the street interview during the extensive health-care debate we had here in America and were asked what you thought of the Obama proposal. I will use italics to identify which word I am accenting in each sentence.

“I support good health-care policies for all!”

“I support good health-care policies for all!”

The first statement could make you seem like a strong believer in the Obama policy as you wish to emphasize your support of the bill. The second one by contrast could be seen as a challenge to the bill in which you are saying that you support good health-care policies, but you do not see this policy as good.

A great place to watch for something like this would be in fact, the evening news. When a word is emphasized, just watch and see why it’s emphasized. Now not all emphases are wrong. There is a place for emphasis. The goal is to emphasize where you can to make your meaning as clear as you need it to be. There are times you might want to be ambiguous, but if you want to be as clear as you can, watch what you emphasize.

We shall continue tomorrow.