The term “logic” refers to the science that studies the principles of correct reasoning. Logic requires the act of reasoning by humans in order to form thoughts and opinions, as well as classifications and judgments. The foundation of a logical argument is its proposition, or statement. The proposition is either accurate (true) or not accurate (false). The argument is then built on premises. The premises are the propositions used to build the argument. Then an inference is made from the premises. Finally, a conclusion is drawn.
Understanding Logic Through Examples
- Deductive – This type of reasoning provides complete evidence of the truth of its conclusion. It uses a specific and accurate premise that leads to a specific and accurate conclusion. With correct premises, the conclusion to this type of argument is verifiable and correct.
- Inductive – This type of reasoning is “bottom up,” meaning that it takes specific information and makes a broad generalization that is considered probable, allowing for the fact that the conclusion may not be accurate. This type of reasoning usually involves a rule being established based on a series of repeated experiences.
Examples of Deductive and Inductive Logic
- All squares are rectangles. All rectangles have four sides. Logic, therefore, tells you that all squares have four sides.
- It is dangerous to drive when it is snowing. It is snowing now. Logic tells you that it would be dangerous to drive right now.
- All dogs have a good sense of smell. Bailey is a dog. Therefore, deductive reasoning logic tells you that Bailey has a good sense of smell.
- All seniors are bad drivers. Mr. Jones is 70 years old and you won’t let him drive your car because you think he is an unsafe driver.
- When it rains the trees get wet. The trees are wet this morning, so it rained last night.
- All trees have trunks. An oak tree is a tree. Therefore, deductive reasoning tells you that the oak tree has a trunk.
- An umbrella prevents you from getting wet in the rain. Ashley took her umbrella and she did not get wet. In this case, you could use inductive reasoning to offer an opinion that it was probably raining. Your concluson, however, would not necessarily be accurate because Ashley would have remained dry whether it rained and she had an umbrella, or whether it did not rain at all.
- Every three year old you see at the park every afternoon spends most of their time crying and screaming. Your conclusion is that all three year olds spend their afternoon screaming.
- Every house that burned down on the block was caused by faulty wiring. You conclusion is that all homes on the block have faulty wiring.
- Red lights prevent accidents. Mike did not have an accident, therefore Mike stopped at a red light. This is an example of inductive reasoning; but, it is faulty reasoning because Mike might not have encountered any traffic signals at all. Therefore, he might have been able to avoid accidents even without stopping at a red light.
As these examples show, you can use logic to solve problems and to draw conclusions. Sometimes those conclusions are correct conclusions and sometimes they are inaccurate. When you use deductive reasoning, you arrive at correct logical arguments while inductive reasoning may or may not provide you with a correct outcome.