# Deductive Reasoning

Topics: Logic, Reasoning, Argument form Pages: 4 (1272 words) Published: October 3, 2005
Deductive Reasoning
In order to fully understand deductive reasoning, there are certain points to be noted. First, what is the nature of deductive reasoning? Logical strength is defined as the property of an argument whose premises, if true provide support for its conclusion. Deductive and inductive arguments are also distinguished based on the point that logical strength is a matter of degree. This distinction makes it necessary to understand the nature of deductive reasoning. Therefore, deductive arguments are those whose premises guarantee the truth of the conclusion, and inductive arguments are those whose premises make it reasonable to accept the conclusion though do not absolutely guarantee its truth. Deductive reasoning is somewhat different from an inductive argument (truth of premises doesn't guarantee the truth of conclusion) for the conclusion can't possibly be false if the premises are true. Consider the following example.

If you like listening to Metallica then you prefer rock music.
If you prefer rock music then you are a rocker.
Therefore, if you like listening to Metallica then you are a rocker. In this argument, it can be said that the truth of the conclusion is guaranteed if its premises are true, unless at least one of the premises is false. Deductive arguments are able to guarantee their conclusions because the logical strength doesn't depend upon the specific content but on their form or structure. * It is defined that the truth of the premises of a deductive argument guarantees the conclusion due to its form or structure. Then, as shown by the examples the, form of implication is followed (if-then statement) Every deductive argument has at least one truth-functional statement. It is necessary to understand what a truth-functional statement is order to understand deductive reasoning. Truth functional statements are a sub-class of complex statements (a kind of statement that contains another statement as a component part as opposed to...