Ever heard someone say they know earth is billions of years old because of radiometric dating? On the surface, that may sound like a fairly reasonable, scientific thing to say. What many people do not realize is that this argument makes a masked, major logical fallacy called “circular reasoning”. Circular reasoning (also called “begging the question” or in Latin, “petito principii”) is when a person assumes the very point they are trying to prove. Simply put, the math behind radiometric dating methods must assume uniformitarianism; that is, the idea that nature has always behaved the same way it does today (i.e., without supernatural intervention), which goes against supernatural Biblical accounts of creation and the global flood. It is circular reasoning because they are using a method that assumes uniformitarianism to prove their point of uniformitarianism (lots more on radioisotope dating here).
Another good example of circular reasoning is when a person who denies Biblical truth uses the principle of induction to establish scientific claims. For instance, a toddler drops something from his high chair and hears a satisfactory noise when it hits the floor. He repeats this process several times, getting the same satisfactory results, and after many months of experimentation at different times and under varying conditions, he concludes that, “if I drop something, it will fall to the ground and make a satisfactory noise”. The toddler is using the principle of induction, now assuming that the world in the future will function in basically the same way it has in the past. We could not do science at all without induction. But, the atheist has no logical reason to believe that the universe will continue to function in the same way it has, besides saying that induction has worked in the past (which of course, is circular reasoning because he’s using induction in attempt to prove induction).
“While the earth remaineth, seedtime and harvest, and cold and heat, and summer and winter, and day and night shall not cease.” ~ Genesis 8:22
What about when a Christian says “the Bible must be true because it says it is the Word of God, and it is impossible for God to lie (see Heb. 6:18)” ? Is that circular reasoning? Yes, it is circular reasoning, but circular reasoning is a very unique fallacy because it can sometimes actually be valid (see Dr. Lisle’s The Ultimate Proof of Creation). It all depends on the assumptions that are being made. Because the Bible is our ultimate standard – what we measure everything else by – it is important that it reaffirms itself as the true and reliable Word of God. We should be cautious about saying “science proves the Bible” because by definition, our ultimate standard cannot really be proved or disproved by anything but itself.
According to Dr. Jason Lisle, “an ultimate standard must do more than simply prove itself. It must provide a basis for proving absolutely everything that is knowable.” (The Ultimate Proof of Creation, pg. 146) The atheistic/evolutionary worldview fails here, because it is self-refuting. This is because the induction and laws of logic that science is based off are completely arbitrary and illogical without the God Who created the mind (more on this topic here). Laws of logic are a reflection of the way God thinks, but without God, logic is no longer logical.
“For of Him, and through Him, and to Him, are all things: to Whom be glory for ever. Amen”
Copyright Sara J. Bruegel, 2015. Used with permission.
Discerning Truth, by Dr. Jason Lisle
The Ultimate Proof of Creation, by Dr. Jason Lisle
The Fallacy Detective, by Hans and Nathanial Bluedorn