Destructive Dilemma (DD) is one of the nine rules of inference presented in this module. A rule of inference is simply a valid argument form. We previously discussed four valid argument forms, including Affirming the Antecedent (also known as Modus Ponens) and Denying the Consequent (also known as Modus Tollens). This is what Destructive Dilemma looks like in symbolized form: (P → Q) & (R → S) ~Q v ~S .: ~P v ~R There are two main things you’ll need to do. Part I Define the variables like this: P = ? Q = ? R = ? S = ? In other words, come up with something that “P” can stand for (use your imagination), come up with something “Q” can stand for, etc. Each letter should be defined as a grammatically complete statement. Part II Based on how you defined the letters, translate the symbolized argument into ordinary English by writing it out as a paragraph. Notice that the first premise needs to be a big conjunction (instead of two separate conditionals).