Logic

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Logic is used when you are problem solving. There are two main forms of logic: inductive reasoning and deductive reasoning. Inductive reasoning involves patterns to make a conjecture. A conjecture is a conclusion made from observing evidence. Although inductive reasoning works some of the time, it may not be true all of the time. The following picture is a good example of inductive reasoning. I just drew these polygons as I was going along. What color polygon do you think would be next???

You might think the green rectangle would be next. If the pattern held true, it would be next, but patterns don't always hold true. To be honest, I was thinking of drawing a blue pentagon next. As you have just found out, inductive reasoning works in some cases, but not in all!

Deductive reasoning, unlike inductive reasoning, DOES work all of the time. Deductive reasoning is drawing conclusions from given information by using rules of logic. We must be able to justify, or give a reason for, any statement we make. To make any statement using deductive reasoning, you must use defined terms, theorems, and postulates. A theorem is possible to prove deductively. You cannont, however, prove anything unless you use postulates. Postulates are assumed to be true without proof. An example of a postulate is: "You are looking at your computer screen." This does not need to be proven because it is obvious that you are looking at your computer screen. A theorem might be: "12 * 24 - 10 = 278." You don't automatically know for sure that this is true so you have to use postulates to prove this. Work it out to be sure.

Both types of reasoning are useful. Lawyers use deductive reasoning to prove things true deyond doubt. Scientist use both types of reasoning when performing experiments.

Now let's learn about the joy of Venn diagrams...

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