5.4. Extreme measures

5.4.0. Overview

There are two further rules for the conditional that reflect its truth table in very direct ways.

5.4.1. Last resorts
We do not always have the opportunity to exploit a conditional by detachment, so we need means to exploit one in a reductio.

5.4.2. Optional extras
The principle of weakening for the conditional provides the basis for an attachment rule that is occasionally useful.