Reasoning: Inductive vs Deductive

A couple of years ago, a new topic came up during math tutoring:  deductive reasoning vs inductive reasoning.  What’s the difference?

There are many ways to explain how the two are different.  I’ll explain it this way:

With inductive reasoning, you notice a few similar situations that lead to the same outcome.  You ask, “Will that outcome always happen for situations like these?”  Here’s an example:  imagine you move to a new town in a foreign country.  You don’t know the local customs.  However, the first Sunday you are there, a festival happens in the streets.  The following Sunday, the festival repeats.  You ask yourself, “I wonder if every Sunday, there’s a festival in the streets?”  That’s inductive reasoning.

You use deductive reasoning to arrive at new facts from ones you already know.  For example, if the ticket price on an item is $100 and the sales tax is 12%, you can deduce that you’ll be paying $112 at the register.  In complex cases, such as a sudoku puzzle, the original few given facts lead the puzzler to new conclusions that lead, ultimately, to the solution.

Note that with inductive reasoning, you develop a hunch that may still be wrong.  With deductive reasoning, you are often funneled to one right conclusion.

Scientists who do experiments often begin by using inductive reasoning.  Deductive reasoning is the one a detective might more likely use.

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.