Thursday, February 10, 2011

Inductive vs. Deductive Reasoning

Inductive and deductive reasoning are both forms of logic used to establish hypotheses, but the methods are different. Deductive reasoning uses generalizations to make a specific conclusion. Inductive reasoning takes specific events and draws a generalization from those.

Deductive reasoning is shown in processes like the scientific method. You can phrase a hypothesis in an "If, then" statement, describe the result following "but" and draw a conclusion with a "therefore." If we mix two chemicals and a precipitate forms, then the chemicals are at least partly soluble in one another, but no precipitate formed when we mixed the chemicals, therefore the chemicals are not soluble in one another.

Inductive reasoning is the opposite of deductive reasoning. You take a bunch of different situations and examine the commonality of them in order to generalize a main rule for them all. Draw 4 different triangles. If you examine them all, you find that the angles of each triangle add up to 180 degress. From these separate instances, we draw one conclusive generalization that for any triangle, the angles will add up to 180 degrees.