Consider the reasons .

Note that the product of these two ratios is 1, that is, .

In this case we can state that are **inverse reasons**.

Example:

are inverse reasons because .

Note that, in inverse reasons, the antecedent of one is the consequence of the other, and vice versa.

Comments:

1) A zero antecedent ratio has no inverse.

2) To determine the inverse ratio of a given reason, we must exchange (exchange) its terms. Example:

The inverse of .

Next: Equivalent Reasons