Deductive or Inductive Reasoning

Deductive or inductive reasoning?

What are they and how are they different?

Deductive Reasoning

Deductive reasoning is finding and giving evidence as proof that a specific statement is true. For example, if someone shows us a certain polygon and tells us that it is a square, how do we know that it is really a square? We start to look for the facts we need to prove that this polygon really is a square. Therefore we need to highlight the characteristics that a square has, and if this polygon we are shown has the characteristics we are looking for, then it must be a square!

Does the polygon have these characteristics?

4 sides 

All sides equal

All internal angles are 90°

If this is true of the polygon, then it is a square!

Inductive Reasoning

Inductive reasoning is taking what we already know, and predicting what the outcome will be. We observe patterns that we see and then we can make conclusions based on those patterns. For example, if we are given a series of images, and based off of those images we are asked to provide the next image without having previously seen it, but we can give it only based off of the facts that we have so far. 

If we are giving these images and asked to give the next image in the model, can we do so by using inductive reasoning?

We know that each figure adds one more row of dots than the figure before it.

By using inductive reasoning we can conclude that the next image would look like this:

And that, my friends, is deductive reasoning verses inductive reasoning! 

It's necessary in math but also in everyday life as it is a natural way of thinking and reasoning. Encourage your students to learn the difference between these 2 types of reasonings by doing different activities with them. Now notice ways how you use these types of reasoning in daily life!

For more a video teaching more on deductive reasoning vs inductive reason click here