Feb 202015

Logic in apologeticsThe use of logic is very important when defending the faith. God has given us all logic and reason as a gift so that we can think straight. It originates from Him.

We can be very confident in what we believe in, but we should be able to explain why we believe what we do. And a good way of explaining ourselves is through logical arguments.

Logic is a system of reasoning, it is the principle of proper thinking used to arrive at correct conclusions.

It is worth bearing in mind that it is not logic that saves anybody and sometimes, people are so dead-set against Christianity that they are prepared to dispense and abandon reasoned logic.

Logic is used to remove intellectual barriers that hinder people coming to Christ. It can be used powerfully by Christians (and non-Christians) but it does have its limits.

Logic, as you might imagine has a number of principles and laws that govern the validity of its arguments.

  • The first law of logic is the law of identity. This simply states something is what it is and not what it is not. e.g. a dog is a dog, it is not a cat!
  • The second law of logic is the law of non-contradiction. This means that something cannot be both true and false at the same time (and in the same way) In other words, two contradictory statements cannot both be true. e.g. my only pet is a dog, my only pet is a cat.
  • The third law of logic is the law of excluded middle. This is simply that a statement is either true or false. e.g. My name is Adrian is a true statement, I am a girl is a false statement.

To be able to utilise these laws we need to take careful note on what people are saying to us, making sure we fully understand what they are saying and the arguments they use. Sometimes they argue from what is called a ‘false premise’ this is where they state something which isn’t actually true. we need to be aware of these because they are very common. It can help to repeat back to the person what we understand they are saying to avoid any amibiguity. When we are satisfied we have understood them, we can then respond with reasoned and rational comments.

As I cover a few tough questions over the coming weeks, you will see logic quite often comes into play.

Let me leave you with a problem some people try to trip Christians up with, which appears quite clever on the surface but actually breaches a fundamental law of logic. Have you ever heard the question: “Could God make a rock that is so big that He couldn’t lift it?” This is actually an absurd statement and contradicts the second law of logic, the law of non-contradiction. God by definition is infinite. In that statement you are also saying He is finite (limited). He cannot be infinite and finite at the same time. It is a logical fallacy and therefore an illogical statement. To put it simply you are saying that God is God and not God at the same time.

If you want to test how logically you think, here is a website you can test yourself on


Lastly as I was researching this subject I found a really engaging, funny and informative youtube video on logic and so I have posted it below

 February 20, 2015  Posted by at 12:00 pm Apologetics No Responses »